/** * @file flecs.h * @brief Flecs public API. * * This file contains the public API for Flecs. */ #ifndef FLECS_H #define FLECS_H /** * @defgroup c C API * * @{ * @} */ /** * @defgroup core Core * @brief Core ECS functionality (entities, storage, queries). * * \ingroup c * @{ */ /** * @defgroup options API defines * @brief Defines for customizing compile time features. * @{ */ /** \def ecs_float_t * Customizable precision for floating point operations */ #ifndef ecs_float_t #define ecs_float_t float #endif /** \def ecs_ftime_t * Customizable precision for scalar time values. Change to double precision for * processes that can run for a long time (e.g. longer than a day). */ #ifndef ecs_ftime_t #define ecs_ftime_t ecs_float_t #endif /** \def FLECS_LEGACY * Define when building for C89 */ // #define FLECS_LEGACY /** \def FLECS_NO_DEPRECATED_WARNINGS * disables deprecated warnings */ #define FLECS_NO_DEPRECATED_WARNINGS /** \def FLECS_ACCURATE_COUNTERS * Define to ensure that global counters used for statistics (such as the * allocation counters in the OS API) are accurate in multithreaded * applications, at the cost of increased overhead. */ // #define FLECS_ACCURATE_COUNTERS /* Make sure provided configuration is valid */ #if defined(FLECS_DEBUG) && defined(FLECS_NDEBUG) #error "invalid configuration: cannot both define FLECS_DEBUG and FLECS_NDEBUG" #endif #if defined(FLECS_DEBUG) && defined(NDEBUG) #error "invalid configuration: cannot both define FLECS_DEBUG and NDEBUG" #endif /** \def FLECS_DEBUG * Used for input parameter checking and cheap sanity checks. There are lots of * asserts in every part of the code, so this will slow down applications. */ #if !defined(FLECS_DEBUG) && !defined(FLECS_NDEBUG) #if defined(NDEBUG) #define FLECS_NDEBUG #else #define FLECS_DEBUG #endif #endif /** \def FLECS_SANITIZE * Enables expensive checks that can detect issues early. Recommended for * running tests or when debugging issues. This will severely slow down code. */ #ifdef FLECS_SANITIZE #ifndef FLECS_DEBUG #define FLECS_DEBUG /* If sanitized mode is enabled, so is debug mode */ #endif #endif /* Tip: if you see weird behavior that you think might be a bug, make sure to * test with the FLECS_DEBUG or FLECS_SANITIZE flags enabled. There's a good * chance that this gives you more information about the issue! */ /** \def FLECS_SOFT_ASSERT * Define to not abort for recoverable errors, like invalid parameters. An error * is still thrown to the console. This is recommended for when running inside a * third party runtime, such as the Unreal editor. * * Note that internal sanity checks (ECS_INTERNAL_ERROR) will still abort a * process, as this gives more information than a (likely) subsequent crash. * * When a soft assert occurs, the code will attempt to minimize the number of * side effects of the failed operation, but this may not always be possible. * Even though an application may still be able to continue running after a soft * assert, it should be treated as if in an undefined state. */ // #define FLECS_SOFT_ASSERT /** \def FLECS_KEEP_ASSERT * By default asserts are disabled in release mode, when either FLECS_NDEBUG or * NDEBUG is defined. Defining FLECS_KEEP_ASSERT ensures that asserts are not * disabled. This define can be combined with FLECS_SOFT_ASSERT. */ // #define FLECS_KEEP_ASSERT /** \def FLECS_CUSTOM_BUILD * This macro lets you customize which addons to build flecs with. * Without any addons Flecs is just a minimal ECS storage, but addons add * features such as systems, scheduling and reflection. If an addon is disabled, * it is excluded from the build, so that it consumes no resources. By default * all addons are enabled. * * You can customize a build by either whitelisting or blacklisting addons. To * whitelist addons, first define the FLECS_CUSTOM_BUILD macro, which disables * all addons. You can then manually select the addons you need by defining * their macro, like "FLECS_SYSTEM". * * To blacklist an addon, make sure to *not* define FLECS_CUSTOM_BUILD, and * instead define the addons you don't need by defining FLECS_NO_, for * example "FLECS_NO_SYSTEM". If there are any addons that depend on the * blacklisted addon, an error will be thrown during the build. * * Note that addons can have dependencies on each other. Addons will * automatically enable their dependencies. To see the list of addons that was * compiled in a build, enable tracing before creating the world by doing: * ecs_log_set_level(0); * which outputs the full list of addons Flecs was compiled with. */ // #define FLECS_CUSTOM_BUILD #ifndef FLECS_CUSTOM_BUILD // #define FLECS_C /**< C API convenience macros, always enabled */ #define FLECS_CPP /**< C++ API */ #define FLECS_MODULE /**< Module support */ #define FLECS_PARSER /**< String parser for queries */ #define FLECS_PLECS /**< ECS data definition format */ #define FLECS_RULES /**< Constraint solver for advanced queries */ #define FLECS_SNAPSHOT /**< Snapshot & restore ECS data */ #define FLECS_STATS /**< Access runtime statistics */ #define FLECS_MONITOR /**< Track runtime statistics periodically */ #define FLECS_METRICS /**< Expose component data as statistics */ #define FLECS_ALERTS /**< Monitor conditions for errors */ #define FLECS_SYSTEM /**< System support */ #define FLECS_PIPELINE /**< Pipeline support */ #define FLECS_TIMER /**< Timer support */ #define FLECS_META /**< Reflection support */ #define FLECS_META_C /**< Utilities for populating reflection data */ #define FLECS_UNITS /**< Builtin standard units */ #define FLECS_EXPR /**< Parsing strings to/from component values */ #define FLECS_JSON /**< Parsing JSON to/from component values */ #define FLECS_DOC /**< Document entities & components */ #define FLECS_COREDOC /**< Documentation for core entities & components */ #define FLECS_LOG /**< When enabled ECS provides more detailed logs */ #define FLECS_APP /**< Application addon */ #define FLECS_OS_API_IMPL /**< Default implementation for OS API */ #define FLECS_HTTP /**< Tiny HTTP server for connecting to remote UI */ #define FLECS_REST /**< REST API for querying application data */ // #define FLECS_JOURNAL /**< Journaling addon (disabled by default) */ #endif // ifndef FLECS_CUSTOM_BUILD /** \def FLECS_LOW_FOOTPRINT * Set a number of constants to values that decrease memory footprint, at the * cost of decreased performance. */ // #define FLECS_LOW_FOOTPRINT #ifdef FLECS_LOW_FOOTPRINT #define FLECS_HI_COMPONENT_ID (16) #define FLECS_HI_ID_RECORD_ID (16) #define FLECS_SPARSE_PAGE_BITS (6) #define FLECS_ENTITY_PAGE_BITS (6) #define FLECS_USE_OS_ALLOC #endif /** \def FLECS_HI_COMPONENT_ID * This constant can be used to balance between performance and memory * utilization. The constant is used in two ways: * - Entity ids 0..FLECS_HI_COMPONENT_ID are reserved for component ids. * - Used as lookup array size in table edges. * * Increasing this value increases the size of the lookup array, which allows * fast table traversal, which improves performance of ECS add/remove * operations. Component ids that fall outside of this range use a regular map * lookup, which is slower but more memory efficient. */ #ifndef FLECS_HI_COMPONENT_ID #define FLECS_HI_COMPONENT_ID (256) #endif /** \def FLECS_HI_ID_RECORD_ID * This constant can be used to balance between performance and memory * utilization. The constant is used to determine the size of the id record * lookup array. Id values that fall outside of this range use a regular map * lookup, which is slower but more memory efficient. */ #ifndef FLECS_HI_ID_RECORD_ID #define FLECS_HI_ID_RECORD_ID (1024) #endif /** \def FLECS_SPARSE_PAGE_BITS * This constant is used to determine the number of bits of an id that is used * to determine the page index when used with a sparse set. The number of bits * determines the page size, which is (1 << bits). * Lower values decrease memory utilization, at the cost of more allocations. */ #ifndef FLECS_SPARSE_PAGE_BITS #define FLECS_SPARSE_PAGE_BITS (12) #endif /** \def FLECS_ENTITY_PAGE_BITS * Same as FLECS_SPARSE_PAGE_BITS, but for the entity index. */ #ifndef FLECS_ENTITY_PAGE_BITS #define FLECS_ENTITY_PAGE_BITS (12) #endif /** \def FLECS_USE_OS_ALLOC * When enabled, Flecs will use the OS allocator provided in the OS API directly * instead of the builtin block allocator. This can decrease memory utilization * as memory will be freed more often, at the cost of decreased performance. */ // #define FLECS_USE_OS_ALLOC /** \def FLECS_ID_DESC_MAX * Maximum number of ids to add ecs_entity_desc_t / ecs_bulk_desc_t */ #ifndef FLECS_ID_DESC_MAX #define FLECS_ID_DESC_MAX (32) #endif /** \def FLECS_TERM_DESC_MAX * Maximum number of terms in ecs_filter_desc_t */ #define FLECS_TERM_DESC_MAX (16) /** \def FLECS_EVENT_DESC_MAX * Maximum number of events in ecs_observer_desc_t */ #define FLECS_EVENT_DESC_MAX (8) /** \def FLECS_VARIABLE_COUNT_MAX * Maximum number of query variables per query */ #define FLECS_VARIABLE_COUNT_MAX (64) /** \def FLECS_QUERY_SCOPE_NESTING_MAX * Maximum nesting depth of query scopes */ #define FLECS_QUERY_SCOPE_NESTING_MAX (8) /** @} */ #include "flecs/private/api_defines.h" #include "flecs/private/vec.h" /* Vector datatype */ #include "flecs/private/sparse.h" /* Sparse set */ #include "flecs/private/block_allocator.h" /* Block allocator */ #include "flecs/private/map.h" /* Map */ #include "flecs/private/allocator.h" /* Allocator */ #include "flecs/private/strbuf.h" /* String builder */ #include "flecs/os_api.h" /* Abstraction for operating system functions */ #ifdef __cplusplus extern "C" { #endif /** * @defgroup api_types API types * @brief Public API types. * @{ */ /** * @defgroup core_types Core API Types * @brief Types for core API objects. * @{ */ /** Ids are the things that can be added to an entity. * An id can be an entity or pair, and can have optional id flags. */ typedef uint64_t ecs_id_t; /** An entity identifier. * Entity ids consist out of a number unique to the entity in the lower 32 bits, * and a counter used to track entity liveliness in the upper 32 bits. When an * id is recycled, its generation count is increased. This causes recycled ids * to be very large (>4 billion), which is normal. */ typedef ecs_id_t ecs_entity_t; /** A type is a list of (component) ids. * Types are used to communicate the "type" of an entity. In most type systems a * typeof operation returns a single type. In ECS however, an entity can have * multiple components, which is why an ECS type consists of a vector of ids. * * The component ids of a type are sorted, which ensures that it doesn't matter * in which order components are added to an entity. For example, if adding * Position then Velocity would result in type [Position, Velocity], first * adding Velocity then Position would also result in type [Position, Velocity]. * * Entities are grouped together by type in the ECS storage in tables. The * storage has exactly one table per unique type that is created by the * application that stores all entities and components for that type. This is * also referred to as an archetype. */ typedef struct { ecs_id_t *array; int32_t count; } ecs_type_t; /** A world is the container for all ECS data and supporting features. * Applications can have multiple worlds, though in most cases will only need * one. Worlds are isolated from each other, and can have separate sets of * systems, components, modules etc. * * If an application has multiple worlds with overlapping components, it is * common (though not strictly required) to use the same component ids across * worlds, which can be achieved by declaring a global component id variable. * To do this in the C API, see the entities/fwd_component_decl example. The * C++ API automatically synchronizes component ids between worlds. * * Component id conflicts between worlds can occur when a world has already used * an id for something else. There are a few ways to avoid this: * * - Ensure to register the same components in each world, in the same order. * - Create a dummy world in which all components are preregistered which * initializes the global id variables. * * In some use cases, typically when writing tests, multiple worlds are created * and deleted with different components, registered in different order. To * ensure isolation between tests, the C++ API has a `flecs::reset` function * that forces the API to ignore the old component ids. */ typedef struct ecs_world_t ecs_world_t; /** A table stores entities and components for a specific type. */ typedef struct ecs_table_t ecs_table_t; /** A term is a single element in a query. */ typedef struct ecs_term_t ecs_term_t; /** A filter is an iterable data structure that describes a query. * Filters are used by the various query implementations in Flecs, like queries, * observers and rules, to describe a query. Filters themselves can also be * iterated. */ typedef struct ecs_filter_t ecs_filter_t; /** A query that caches its results. * Queries are the fastest mechanism for finding and iterating over entities. * Queries cache results as a list of matching tables (vs. individual entities). * * This has several advantages: * - Matching is only performed when new tables are created, which is infrequent * - Iterating a query just walks over the cache, no actual searching is needed * - Iteration is table-based, which allows for direct iteration of underlying * component arrays, providing good cache locality. * * While queries are the fastest mechanism to iterate entiites, they are slower * to create than other mechanisms, as a result of having to build the cache * first. For this reason queries are best suited for use cases where a single * query can be reused many times (like is the case for systems). * * For ad-hoc queries it is recommended to use filters or rules instead, which * are slower to iterate, but much faster to create. Applications should at all * times avoid frequent creation/deletion of queries. */ typedef struct ecs_query_t ecs_query_t; /** A rule is a query with advanced graph traversal features. * Rules are fast uncached queries with support for advanced graph features such * as the usage of query variables. A simple example of a rule that matches all * spaceship entities docked to a planet: * SpaceShip, (DockedTo, $planet), Planet($planet) * * Here, the rule traverses the DockedTo relationship, and matches Planet on the * target of this relationship. Through the usage of variables rules can match * arbitrary patterns against entity graphs. Other features supported * exclusively by rules are: * - Component inheritance * - Transitivity * * Rules have similar iteration performance to filters, but are slower than * queries. Rules and filters will eventually be merged into a single query * implementation. Features still lacking for rules are: * - Up traversal * - AndFrom, OrFrom, NotFrom operators */ typedef struct ecs_rule_t ecs_rule_t; /** An observer is a system that is invoked when an event matches its query. * Observers allow applications to respond to specific events, such as adding or * removing a component. Observers are created by both specifying a query and * a list of event kinds that should be listened for. An example of an observer * that triggers when a Position component is added to an entity (in C++): * * world.observer() * .event(flecs::OnAdd) * .each([](Position& p) { * // called when Position is added to an entity * }); * * Observer queries can be as complex as filters. Observers only trigger when * the source of the event matches the full observer query. For example, an * OnAdd observer for Position, Velocity will only trigger after both components * have been added to the entity. */ typedef struct ecs_observer_t ecs_observer_t; /** An observable produces events that can be listened for by an observer. * Currently only the world is observable. In the future, queries will become * observable objects as well. */ typedef struct ecs_observable_t ecs_observable_t; /* Type used for iterating iterable objects. * Iterators are a common interface across iterable objects (world, filters, * rules, queries, systems, observers) to provide applications with information * about the currently iterated result, and to store any state required for the * iteration. */ typedef struct ecs_iter_t ecs_iter_t; /** A ref is a fast way to fetch a component for a specific entity. * Refs are a faster alternative to repeatedly calling ecs_get for the same * entity/component combination. When comparing the performance of getting a ref * to calling ecs_get, a ref is typically 3-5x faster. * * Refs achieve this performance by caching internal data structures associated * with the entity and component on the ecs_ref_t object that otherwise would * have to be looked up. */ typedef struct ecs_ref_t ecs_ref_t; /** Type hooks are callbacks associated with component lifecycle events. * Typical examples of lifecycle events are construction, destruction, copying * and moving of components. */ typedef struct ecs_type_hooks_t ecs_type_hooks_t; /** Type information. * Contains information about a (component) type, such as its size and * alignment and type hooks. */ typedef struct ecs_type_info_t ecs_type_info_t; /** Information about an entity, like its table and row. */ typedef struct ecs_record_t ecs_record_t; /** Information about a (component) id, such as type info and tables with the id */ typedef struct ecs_id_record_t ecs_id_record_t; /** Information about where in a table a specific (component) id is stored. */ typedef struct ecs_table_record_t ecs_table_record_t; /** A poly object. * A poly (short for polymorph) object is an object that has a variable list of * capabilities, determined by a mixin table. This is the current list of types * in the flecs API that can be used as an ecs_poly_t: * * - ecs_world_t * - ecs_stage_t * - ecs_query_t * - ecs_filter_t * - ecs_rule_t * - (more to come) * * Functions that accept an ecs_poly_t argument can accept objects of these * types. If the object does not have the requested mixin the API will throw an * assert. * * The poly/mixin framework enables partially overlapping features to be * implemented once, and enables objects of different types to interact with * each other depending on what mixins they have, rather than their type * (in some ways it's like a mini-ECS). Additionally, each poly object has a * header that enables the API to do sanity checking on the input arguments. */ typedef void ecs_poly_t; /** Type that stores poly mixins */ typedef struct ecs_mixins_t ecs_mixins_t; /** Header for ecs_poly_t objects. */ typedef struct ecs_header_t { int32_t magic; /* Magic number verifying it's a flecs object */ int32_t type; /* Magic number indicating which type of flecs object */ ecs_mixins_t *mixins; /* Table with offsets to (optional) mixins */ } ecs_header_t; /** @} */ /** * @defgroup function_types Function types. * @brief Function callback types. * @{ */ /** Function prototype for runnables (systems, observers). * The run callback overrides the default behavior for iterating through the * results of a runnable object. * * The default runnable iterates the iterator, and calls an iter_action (see * below) for each returned result. * * @param it The iterator to be iterated by the runnable. */ typedef void (*ecs_run_action_t)( ecs_iter_t *it); /** Function prototype for iterables. * A system may invoke a callback multiple times, typically once for each * matched table. * * @param it The iterator containing the data for the current match. */ typedef void (*ecs_iter_action_t)( ecs_iter_t *it); /** Function prototype for creating an iterator from a poly. * Used to create iterators from poly objects with the iterable mixin. When a * filter is provided, an array of two iterators must be passed to the function. * This allows the mixin implementation to create a chained iterator when * necessary, which requires two iterator objects. * * @param world The world or stage for which to create the iterator. * @param iterable An iterable poly object. * @param it The iterator to create (out parameter) * @param filter Optional term to filter results. */ typedef void (*ecs_iter_init_action_t)( const ecs_world_t *world, const ecs_poly_t *iterable, ecs_iter_t *it, ecs_term_t *filter); /** Function prototype for iterating an iterator. * Stored inside initialized iterators. This allows an application to * iterate * an iterator without needing to know what created it. * * @param it The iterator to iterate. * @return True if iterator has no more results, false if it does. */ typedef bool (*ecs_iter_next_action_t)( ecs_iter_t *it); /** Function prototype for freeing an iterator. * Free iterator resources. * * @param it The iterator to free. */ typedef void (*ecs_iter_fini_action_t)( ecs_iter_t *it); /** Callback used for comparing components */ typedef int (*ecs_order_by_action_t)( ecs_entity_t e1, const void *ptr1, ecs_entity_t e2, const void *ptr2); /** Callback used for sorting the entire table of components */ typedef void (*ecs_sort_table_action_t)( ecs_world_t* world, ecs_table_t* table, ecs_entity_t* entities, void* ptr, int32_t size, int32_t lo, int32_t hi, ecs_order_by_action_t order_by); /** Callback used for grouping tables in a query */ typedef uint64_t (*ecs_group_by_action_t)( ecs_world_t *world, ecs_table_t *table, ecs_id_t group_id, void *ctx); /* Callback invoked when a query creates a new group. */ typedef void* (*ecs_group_create_action_t)( ecs_world_t *world, uint64_t group_id, void *group_by_ctx); /* from ecs_query_desc_t */ /* Callback invoked when a query deletes an existing group. */ typedef void (*ecs_group_delete_action_t)( ecs_world_t *world, uint64_t group_id, void *group_ctx, /* return value from ecs_group_create_action_t */ void *group_by_ctx); /* from ecs_query_desc_t */ /** Initialization action for modules */ typedef void (*ecs_module_action_t)( ecs_world_t *world); /** Action callback on world exit */ typedef void (*ecs_fini_action_t)( ecs_world_t *world, void *ctx); /** Function to cleanup context data */ typedef void (*ecs_ctx_free_t)( void *ctx); /** Callback used for sorting values */ typedef int (*ecs_compare_action_t)( const void *ptr1, const void *ptr2); /** Callback used for hashing values */ typedef uint64_t (*ecs_hash_value_action_t)( const void *ptr); /** Constructor/destructor callback */ typedef void (*ecs_xtor_t)( void *ptr, int32_t count, const ecs_type_info_t *type_info); /** Copy is invoked when a component is copied into another component. */ typedef void (*ecs_copy_t)( void *dst_ptr, const void *src_ptr, int32_t count, const ecs_type_info_t *type_info); /** Move is invoked when a component is moved to another component. */ typedef void (*ecs_move_t)( void *dst_ptr, void *src_ptr, int32_t count, const ecs_type_info_t *type_info); /* Destructor function for poly objects */ typedef void (*ecs_poly_dtor_t)( ecs_poly_t *poly); /** @} */ /** * @defgroup mixins Poly mixin types. * @brief Mixin types for poly mechanism. * @{ */ /** Iterable mixin. * Allows its container to be iterated. */ typedef struct ecs_iterable_t { ecs_iter_init_action_t init; /**< Callback that creates iterator. */ } ecs_iterable_t; /** @} */ /** * @defgroup query_types Query descriptor types. * @brief Types used to describe queries. * @{ */ /** Specify read/write access for term */ typedef enum ecs_inout_kind_t { EcsInOutDefault, /**< InOut for regular terms, In for shared terms */ EcsInOutNone, /**< Term is neither read nor written */ EcsInOut, /**< Term is both read and written */ EcsIn, /**< Term is only read */ EcsOut, /**< Term is only written */ } ecs_inout_kind_t; /** Specify operator for term */ typedef enum ecs_oper_kind_t { EcsAnd, /**< The term must match */ EcsOr, /**< One of the terms in an or chain must match */ EcsNot, /**< The term must not match */ EcsOptional, /**< The term may match */ EcsAndFrom, /**< Term must match all components from term id */ EcsOrFrom, /**< Term must match at least one component from term id */ EcsNotFrom, /**< Term must match none of the components from term id */ } ecs_oper_kind_t; /* Term id flags */ #define EcsSelf (1u << 1) /**< Match on self */ #define EcsUp (1u << 2) /**< Match by traversing upwards */ #define EcsDown (1u << 3) /**< Match by traversing downwards (derived, cannot be set) */ #define EcsTraverseAll (1u << 4) /**< Match all entities encountered through traversal */ #define EcsCascade (1u << 5) /**< Sort results breadth first */ #define EcsDesc (1u << 6) /**< Iterate groups in descending order */ #define EcsParent (1u << 7) /**< Short for up(ChildOf) */ #define EcsIsVariable (1u << 8) /**< Term id is a variable */ #define EcsIsEntity (1u << 9) /**< Term id is an entity */ #define EcsIsName (1u << 10) /**< Term id is a name (don't attempt to lookup as entity) */ #define EcsFilter (1u << 11) /**< Prevent observer from triggering on term */ #define EcsTraverseFlags (EcsUp|EcsDown|EcsTraverseAll|EcsSelf|EcsCascade|EcsDesc|EcsParent) /* Term flags discovered & set during filter creation. Mostly used internally to * store information relevant to queries. */ #define EcsTermMatchAny (1u << 0) #define EcsTermMatchAnySrc (1u << 1) #define EcsTermSrcFirstEq (1u << 2) #define EcsTermSrcSecondEq (1u << 3) #define EcsTermTransitive (1u << 4) #define EcsTermReflexive (1u << 5) #define EcsTermIdInherited (1u << 6) /* Term flags used for term iteration */ #define EcsTermMatchDisabled (1u << 7) #define EcsTermMatchPrefab (1u << 8) /** Type that describes a single identifier in a term */ typedef struct ecs_term_id_t { ecs_entity_t id; /**< Entity id. If left to 0 and flags does not * specify whether id is an entity or a variable * the id will be initialized to EcsThis. * To explicitly set the id to 0, leave the id * member to 0 and set EcsIsEntity in flags. */ const char *name; /**< Name. This can be either the variable name * (when the EcsIsVariable flag is set) or an * entity name. When ecs_term_t::move is true, * the API assumes ownership over the string and * will free it when the term is destroyed. */ ecs_entity_t trav; /**< Relationship to traverse when looking for the * component. The relationship must have * the Traversable property. Default is IsA. */ ecs_flags32_t flags; /**< Term flags */ } ecs_term_id_t; /** Type that describes a term (single element in a query) */ struct ecs_term_t { ecs_id_t id; /**< Component id to be matched by term. Can be * set directly, or will be populated from the * first/second members, which provide more * flexibility. */ ecs_term_id_t src; /**< Source of term */ ecs_term_id_t first; /**< Component or first element of pair */ ecs_term_id_t second; /**< Second element of pair */ ecs_inout_kind_t inout; /**< Access to contents matched by term */ ecs_oper_kind_t oper; /**< Operator of term */ ecs_id_t id_flags; /**< Id flags of term id */ char *name; /**< Name of term */ int32_t field_index; /**< Index of field for term in iterator */ ecs_id_record_t *idr; /**< Cached pointer to internal index */ ecs_flags16_t flags; /**< Flags that help eval, set by ecs_filter_init */ bool move; /**< Used by internals */ }; /** Use $this variable to initialize user-allocated filter object */ FLECS_API extern ecs_filter_t ECS_FILTER_INIT; /** Filters alllow for ad-hoc quick filtering of entity tables. */ struct ecs_filter_t { ecs_header_t hdr; ecs_term_t *terms; /**< Array containing terms for filter */ int32_t term_count; /**< Number of elements in terms array */ int32_t field_count; /**< Number of fields in iterator for filter */ bool owned; /**< Is filter object owned by filter */ bool terms_owned; /**< Is terms array owned by filter */ ecs_flags32_t flags; /**< Filter flags */ char *variable_names[1]; /**< Placeholder variable names array */ int32_t *sizes; /**< Field size (same for each result) */ /* Mixins */ ecs_entity_t entity; /**< Entity associated with filter (optional) */ ecs_iterable_t iterable; /**< Iterable mixin */ ecs_poly_dtor_t dtor; /**< Dtor mixin */ ecs_world_t *world; /**< World mixin */ }; /* An observer reacts to events matching a filter */ struct ecs_observer_t { ecs_header_t hdr; ecs_filter_t filter; /**< Query for observer */ /* Observer events */ ecs_entity_t events[FLECS_EVENT_DESC_MAX]; int32_t event_count; ecs_iter_action_t callback; /**< See ecs_observer_desc_t::callback */ ecs_run_action_t run; /**< See ecs_observer_desc_t::run */ void *ctx; /**< Callback context */ void *binding_ctx; /**< Binding context (for language bindings) */ ecs_ctx_free_t ctx_free; /**< Callback to free ctx */ ecs_ctx_free_t binding_ctx_free; /**< Callback to free binding_ctx */ ecs_observable_t *observable; /**< Observable for observer */ int32_t *last_event_id; /**< Last handled event id */ int32_t last_event_id_storage; ecs_id_t register_id; /**< Id observer is registered with (single term observers only) */ int32_t term_index; /**< Index of the term in parent observer (single term observers only) */ bool is_monitor; /**< If true, the observer only triggers when the * filter did not match with the entity before * the event happened. */ bool is_multi; /**< If true, the observer triggers on more than one term */ /* Mixins */ ecs_poly_dtor_t dtor; }; /** @} */ /** Type that contains component lifecycle callbacks. * * \ingroup components */ struct ecs_type_hooks_t { ecs_xtor_t ctor; /**< ctor */ ecs_xtor_t dtor; /**< dtor */ ecs_copy_t copy; /**< copy assignment */ ecs_move_t move; /**< move assignment */ /** Ctor + copy */ ecs_copy_t copy_ctor; /** Ctor + move */ ecs_move_t move_ctor; /** Ctor + move + dtor (or move_ctor + dtor). * This combination is typically used when a component is moved from one * location to a new location, like when it is moved to a new table. If * not set explicitly it will be derived from other callbacks. */ ecs_move_t ctor_move_dtor; /** Move + dtor. * This combination is typically used when a component is moved from one * location to an existing location, like what happens during a remove. If * not set explicitly it will be derived from other callbacks. */ ecs_move_t move_dtor; /** Callback that is invoked when an instance of a component is added. This * callback is invoked before triggers are invoked. */ ecs_iter_action_t on_add; /** Callback that is invoked when an instance of the component is set. This * callback is invoked before triggers are invoked, and enable the component * to respond to changes on itself before others can. */ ecs_iter_action_t on_set; /** Callback that is invoked when an instance of the component is removed. * This callback is invoked after the triggers are invoked, and before the * destructor is invoked. */ ecs_iter_action_t on_remove; void *ctx; /**< User defined context */ void *binding_ctx; /**< Language binding context */ ecs_ctx_free_t ctx_free; /**< Callback to free ctx */ ecs_ctx_free_t binding_ctx_free; /**< Callback to free binding_ctx */ }; /** Type that contains component information (passed to ctors/dtors/...) * * \ingroup components */ struct ecs_type_info_t { ecs_size_t size; /**< Size of type */ ecs_size_t alignment; /**< Alignment of type */ ecs_type_hooks_t hooks; /**< Type hooks */ ecs_entity_t component; /**< Handle to component (do not set) */ const char *name; /**< Type name. */ }; #include "flecs/private/api_types.h" /* Supporting API types */ #include "flecs/private/api_support.h" /* Supporting API functions */ #include "flecs/private/vec.h" /* Vector */ #include "flecs/private/hashmap.h" /* Hashmap */ /** Used with ecs_entity_init * * \ingroup entities */ typedef struct ecs_entity_desc_t { int32_t _canary; ecs_entity_t id; /**< Set to modify existing entity (optional) */ const char *name; /**< Name of the entity. If no entity is provided, an * entity with this name will be looked up first. When * an entity is provided, the name will be verified * with the existing entity. */ const char *sep; /**< Optional custom separator for hierarchical names. * Leave to NULL for default ('.') separator. Set to * an empty string to prevent tokenization of name. */ const char *root_sep; /**< Optional, used for identifiers relative to root */ const char *symbol; /**< Optional entity symbol. A symbol is an unscoped * identifier that can be used to lookup an entity. The * primary use case for this is to associate the entity * with a language identifier, such as a type or * function name, where these identifiers differ from * the name they are registered with in flecs. For * example, C type "EcsPosition" might be registered * as "flecs.components.transform.Position", with the * symbol set to "EcsPosition". */ bool use_low_id; /**< When set to true, a low id (typically reserved for * components) will be used to create the entity, if * no id is specified. */ /** Array of ids to add to the new or existing entity. */ ecs_id_t add[FLECS_ID_DESC_MAX]; /** String expression with components to add */ const char *add_expr; } ecs_entity_desc_t; /** Used with ecs_bulk_init * * \ingroup entities */ typedef struct ecs_bulk_desc_t { int32_t _canary; ecs_entity_t *entities; /**< Entities to bulk insert. Entity ids provided by * the application must be empty (cannot * have components). If no entity ids are provided, the * operation will create 'count' new entities. */ int32_t count; /**< Number of entities to create/populate */ ecs_id_t ids[FLECS_ID_DESC_MAX]; /**< Ids to create the entities with */ void **data; /**< Array with component data to insert. Each element in * the array must correspond with an element in the ids * array. If an element in the ids array is a tag, the * data array must contain a NULL. An element may be * set to NULL for a component, in which case the * component will not be set by the operation. */ ecs_table_t *table; /**< Table to insert the entities into. Should not be set * at the same time as ids. When 'table' is set at the * same time as 'data', the elements in the data array * must correspond with the ids in the table's type. */ } ecs_bulk_desc_t; /** Used with ecs_component_init. * * \ingroup components */ typedef struct ecs_component_desc_t { int32_t _canary; /** Existing entity to associate with observer (optional) */ ecs_entity_t entity; /** Parameters for type (size, hooks, ...) */ ecs_type_info_t type; } ecs_component_desc_t; /** Used with ecs_filter_init. * * \ingroup filters */ typedef struct ecs_filter_desc_t { int32_t _canary; /** Terms of the filter. If a filter has more terms than * FLECS_TERM_DESC_MAX use terms_buffer */ ecs_term_t terms[FLECS_TERM_DESC_MAX]; /** For filters with lots of terms an outside array can be provided. */ ecs_term_t *terms_buffer; /** Number of terms in array provided in terms_buffer. */ int32_t terms_buffer_count; /** External storage to prevent allocation of the filter object */ ecs_filter_t *storage; /** When true, terms returned by an iterator may either contain 1 or N * elements, where terms with N elements are owned, and terms with 1 element * are shared, for example from a parent or base entity. When false, the * iterator will at most return 1 element when the result contains both * owned and shared terms. */ bool instanced; /** Flags for advanced usage */ ecs_flags32_t flags; /** Filter expression. Should not be set at the same time as terms array */ const char *expr; /** Entity associated with query (optional) */ ecs_entity_t entity; } ecs_filter_desc_t; /** Used with ecs_query_init. * * \ingroup queries */ typedef struct ecs_query_desc_t { int32_t _canary; /** Filter for the query */ ecs_filter_desc_t filter; /** Component to be used by order_by */ ecs_entity_t order_by_component; /** Callback used for ordering query results. If order_by_id is 0, the * pointer provided to the callback will be NULL. If the callback is not * set, results will not be ordered. */ ecs_order_by_action_t order_by; /** Callback used for ordering query results. Same as order_by, * but more efficient. */ ecs_sort_table_action_t sort_table; /** Id to be used by group_by. This id is passed to the group_by function and * can be used identify the part of an entity type that should be used for * grouping. */ ecs_id_t group_by_id; /** Callback used for grouping results. If the callback is not set, results * will not be grouped. When set, this callback will be used to calculate a * "rank" for each entity (table) based on its components. This rank is then * used to sort entities (tables), so that entities (tables) of the same * rank are "grouped" together when iterated. */ ecs_group_by_action_t group_by; /** Callback that is invoked when a new group is created. The return value of * the callback is stored as context for a group. */ ecs_group_create_action_t on_group_create; /** Callback that is invoked when an existing group is deleted. The return * value of the on_group_create callback is passed as context parameter. */ ecs_group_delete_action_t on_group_delete; /** Context to pass to group_by */ void *group_by_ctx; /** Function to free group_by_ctx */ ecs_ctx_free_t group_by_ctx_free; /** If set, the query will be created as a subquery. A subquery matches at * most a subset of its parent query. Subqueries do not directly receive * (table) notifications from the world. Instead parent queries forward * results to subqueries. This can improve matching performance, as fewer * queries need to be matched with new tables. * Subqueries can be nested. */ ecs_query_t *parent; /** User context to pass to callback */ void *ctx; /** Context to be used for language bindings */ void *binding_ctx; /** Callback to free ctx */ ecs_ctx_free_t ctx_free; /** Callback to free binding_ctx */ ecs_ctx_free_t binding_ctx_free; } ecs_query_desc_t; /** Used with ecs_observer_init. * * \ingroup observers */ typedef struct ecs_observer_desc_t { int32_t _canary; /** Existing entity to associate with observer (optional) */ ecs_entity_t entity; /** Filter for observer */ ecs_filter_desc_t filter; /** Events to observe (OnAdd, OnRemove, OnSet, UnSet) */ ecs_entity_t events[FLECS_EVENT_DESC_MAX]; /** When observer is created, generate events from existing data. For example, * EcsOnAdd Position would match all existing instances of Position. * This is only supported for events that are iterable (see EcsIterable) */ bool yield_existing; /** Callback to invoke on an event, invoked when the observer matches. */ ecs_iter_action_t callback; /** Callback invoked on an event. When left to NULL the default runner * is used which matches the event with the observer's filter, and calls * 'callback' when it matches. * A reason to override the run function is to improve performance, if there * are more efficient way to test whether an event matches the observer than * the general purpose query matcher. */ ecs_run_action_t run; /** User context to pass to callback */ void *ctx; /** Context to be used for language bindings */ void *binding_ctx; /** Callback to free ctx */ ecs_ctx_free_t ctx_free; /** Callback to free binding_ctx */ ecs_ctx_free_t binding_ctx_free; /** Observable with which to register the observer */ ecs_poly_t *observable; /** Optional shared last event id for multiple observers. Ensures only one * of the observers with the shared id gets triggered for an event */ int32_t *last_event_id; /** Used for internal purposes */ int32_t term_index; } ecs_observer_desc_t; /** Used with ecs_emit. * * \ingroup observers */ typedef struct ecs_event_desc_t { /** The event id. Only triggers for the specified event will be notified */ ecs_entity_t event; /** Component ids. Only triggers with a matching component id will be * notified. Observers are guaranteed to get notified once, even if they * match more than one id. */ const ecs_type_t *ids; /** The table for which to notify. */ ecs_table_t *table; /** Optional 2nd table to notify. This can be used to communicate the * previous or next table, in case an entity is moved between tables. */ ecs_table_t *other_table; /** Limit notified entities to ones starting from offset (row) in table */ int32_t offset; /** Limit number of notified entities to count. offset+count must be less * than the total number of entities in the table. If left to 0, it will be * automatically determined by doing ecs_table_count(table) - offset. */ int32_t count; /** Single-entity alternative to setting table / offset / count */ ecs_entity_t entity; /** Optional context. Assigned to iter param member */ const void *param; /** Observable (usually the world) */ ecs_poly_t *observable; /** Event flags */ ecs_flags32_t flags; } ecs_event_desc_t; /** * @defgroup misc_types Miscellaneous types * @brief Types used to create entities, observers, queries and more. * @{ */ /* Utility to hold a value of a dynamic type */ typedef struct ecs_value_t { ecs_entity_t type; void *ptr; } ecs_value_t; /** Type that contains information about the world. */ typedef struct ecs_world_info_t { ecs_entity_t last_component_id; /**< Last issued component entity id */ ecs_entity_t min_id; /**< First allowed entity id */ ecs_entity_t max_id; /**< Last allowed entity id */ ecs_ftime_t delta_time_raw; /**< Raw delta time (no time scaling) */ ecs_ftime_t delta_time; /**< Time passed to or computed by ecs_progress */ ecs_ftime_t time_scale; /**< Time scale applied to delta_time */ ecs_ftime_t target_fps; /**< Target fps */ ecs_ftime_t frame_time_total; /**< Total time spent processing a frame */ ecs_ftime_t system_time_total; /**< Total time spent in systems */ ecs_ftime_t emit_time_total; /**< Total time spent notifying observers */ ecs_ftime_t merge_time_total; /**< Total time spent in merges */ ecs_ftime_t world_time_total; /**< Time elapsed in simulation */ ecs_ftime_t world_time_total_raw; /**< Time elapsed in simulation (no scaling) */ ecs_ftime_t rematch_time_total; /**< Time spent on query rematching */ int64_t frame_count_total; /**< Total number of frames */ int64_t merge_count_total; /**< Total number of merges */ int64_t rematch_count_total; /**< Total number of rematches */ int64_t id_create_total; /**< Total number of times a new id was created */ int64_t id_delete_total; /**< Total number of times an id was deleted */ int64_t table_create_total; /**< Total number of times a table was created */ int64_t table_delete_total; /**< Total number of times a table was deleted */ int64_t pipeline_build_count_total; /**< Total number of pipeline builds */ int64_t systems_ran_frame; /**< Total number of systems ran in last frame */ int64_t observers_ran_frame; /**< Total number of times observer was invoked */ int32_t id_count; /**< Number of ids in the world (excluding wildcards) */ int32_t tag_id_count; /**< Number of tag (no data) ids in the world */ int32_t component_id_count; /**< Number of component (data) ids in the world */ int32_t pair_id_count; /**< Number of pair ids in the world */ int32_t wildcard_id_count; /**< Number of wildcard ids */ int32_t table_count; /**< Number of tables */ int32_t tag_table_count; /**< Number of tag-only tables */ int32_t trivial_table_count; /**< Number of tables with trivial components (no lifecycle callbacks) */ int32_t empty_table_count; /**< Number of tables without entities */ int32_t table_record_count; /**< Total number of table records (entries in table caches) */ int32_t table_storage_count; /**< Total number of table storages */ /* -- Command counts -- */ struct { int64_t add_count; /**< add commands processed */ int64_t remove_count; /**< remove commands processed */ int64_t delete_count; /**< delete commands processed */ int64_t clear_count; /**< clear commands processed */ int64_t set_count; /**< set commands processed */ int64_t get_mut_count; /**< get_mut/emplace commands processed */ int64_t modified_count; /**< modified commands processed */ int64_t other_count; /**< other commands processed */ int64_t discard_count; /**< commands discarded, happens when entity is no longer alive when running the command */ int64_t batched_entity_count; /**< entities for which commands were batched */ int64_t batched_command_count; /**< commands batched */ } cmd; const char *name_prefix; /**< Value set by ecs_set_name_prefix. Used * to remove library prefixes of symbol * names (such as Ecs, ecs_) when * registering them as names. */ } ecs_world_info_t; /** Type that contains information about a query group. */ typedef struct ecs_query_group_info_t { int32_t match_count; /**< How often tables have been matched/unmatched */ int32_t table_count; /**< Number of tables in group */ void *ctx; /**< Group context, returned by on_group_create */ } ecs_query_group_info_t; /** @} */ /** * @defgroup builtin_components Builtin component types. * @brief Types that represent builtin components. * @{ */ /** A (string) identifier. Used as pair with EcsName and EcsSymbol tags */ typedef struct EcsIdentifier { char *value; /**< Identifier string */ ecs_size_t length; /**< Length of identifier */ uint64_t hash; /**< Hash of current value */ uint64_t index_hash; /**< Hash of existing record in current index */ ecs_hashmap_t *index; /**< Current index */ } EcsIdentifier; /** Component information. */ typedef struct EcsComponent { ecs_size_t size; /**< Component size */ ecs_size_t alignment; /**< Component alignment */ } EcsComponent; /** Component for storing a poly object */ typedef struct EcsPoly { ecs_poly_t *poly; /**< Pointer to poly object */ } EcsPoly; /** Target data for flattened relationships. */ typedef struct EcsTarget { int32_t count; ecs_record_t *target; } EcsTarget; /** Component for iterable entities */ typedef ecs_iterable_t EcsIterable; /** @} */ /** @} */ /* Only include deprecated definitions if deprecated addon is required */ #ifdef FLECS_DEPRECATED #include "flecs/addons/deprecated.h" #endif /** * @defgroup api_constants API Constants * @brief Public API constants. * @{ */ /** * @defgroup id_flags Component id flags. * @brief Id flags are bits that can be set on an id (ecs_id_t). * @{ */ /** Indicates that the id is a pair. */ FLECS_API extern const ecs_id_t ECS_PAIR; /** Automatically override component when it is inherited */ FLECS_API extern const ecs_id_t ECS_OVERRIDE; /** Adds bitset to storage which allows component to be enabled/disabled */ FLECS_API extern const ecs_id_t ECS_TOGGLE; /** Include all components from entity to which AND is applied */ FLECS_API extern const ecs_id_t ECS_AND; /** @} */ /** * @defgroup builtin_tags Builtin component ids. * @{ */ /* Builtin component ids */ FLECS_API extern const ecs_entity_t ecs_id(EcsComponent); FLECS_API extern const ecs_entity_t ecs_id(EcsIdentifier); FLECS_API extern const ecs_entity_t ecs_id(EcsIterable); FLECS_API extern const ecs_entity_t ecs_id(EcsPoly); FLECS_API extern const ecs_entity_t EcsQuery; FLECS_API extern const ecs_entity_t EcsObserver; /* System module component ids */ FLECS_API extern const ecs_entity_t EcsSystem; FLECS_API extern const ecs_entity_t ecs_id(EcsTickSource); /* Pipeline module component ids */ FLECS_API extern const ecs_entity_t ecs_id(EcsPipelineQuery); /* Timer module component ids */ FLECS_API extern const ecs_entity_t ecs_id(EcsTimer); FLECS_API extern const ecs_entity_t ecs_id(EcsRateFilter); /** Root scope for builtin flecs entities */ FLECS_API extern const ecs_entity_t EcsFlecs; /** Core module scope */ FLECS_API extern const ecs_entity_t EcsFlecsCore; /** Entity associated with world (used for "attaching" components to world) */ FLECS_API extern const ecs_entity_t EcsWorld; /** Wildcard entity ("*"). Matches any id, returns all matches. */ FLECS_API extern const ecs_entity_t EcsWildcard; /** Any entity ("_"). Matches any id, returns only the first. */ FLECS_API extern const ecs_entity_t EcsAny; /** This entity. Default source for queries. */ FLECS_API extern const ecs_entity_t EcsThis; /** Variable entity ("$"). Used in expressions to prefix variable names */ FLECS_API extern const ecs_entity_t EcsVariable; /** Marks a relationship as transitive. * Behavior: * if R(X, Y) and R(Y, Z) then R(X, Z) */ FLECS_API extern const ecs_entity_t EcsTransitive; /** Marks a relatoinship as reflexive. * Behavior: * R(X, X) == true */ FLECS_API extern const ecs_entity_t EcsReflexive; /** Ensures that entity/component cannot be used as target in IsA relationship. * Final can improve the performance of rule-based queries, as they will not * attempt to substitute a final component with its subsets. * * Behavior: * if IsA(X, Y) and Final(Y) throw error */ FLECS_API extern const ecs_entity_t EcsFinal; /** Ensures that component is never inherited from an IsA target. * * Behavior: * if DontInherit(X) and X(B) and IsA(A, B) then X(A) is false. */ FLECS_API extern const ecs_entity_t EcsDontInherit; /** Ensures a component is always overridden. * * Behavior: * As if the component is added together with OVERRIDE | T */ FLECS_API extern const ecs_entity_t EcsAlwaysOverride; /** Marks relationship as commutative. * Behavior: * if R(X, Y) then R(Y, X) */ FLECS_API extern const ecs_entity_t EcsSymmetric; /** Can be added to relationship to indicate that the relationship can only occur * once on an entity. Adding a 2nd instance will replace the 1st. * * Behavior: * R(X, Y) + R(X, Z) = R(X, Z) */ FLECS_API extern const ecs_entity_t EcsExclusive; /** Marks a relationship as acyclic. Acyclic relationships may not form cycles. */ FLECS_API extern const ecs_entity_t EcsAcyclic; /** Marks a relationship as traversable. Traversable relationships may be * traversed with "up" queries. Traversable relationships are acyclic. */ FLECS_API extern const ecs_entity_t EcsTraversable; /** Ensure that a component always is added together with another component. * * Behavior: * If With(R, O) and R(X) then O(X) * If With(R, O) and R(X, Y) then O(X, Y) */ FLECS_API extern const ecs_entity_t EcsWith; /** Ensure that relationship target is child of specified entity. * * Behavior: * If OneOf(R, O) and R(X, Y), Y must be a child of O * If OneOf(R) and R(X, Y), Y must be a child of R */ FLECS_API extern const ecs_entity_t EcsOneOf; /** Can be added to relationship to indicate that it should never hold data, * even when it or the relationship target is a component. */ FLECS_API extern const ecs_entity_t EcsTag; /** Tag to indicate that relationship is stored as union. Union relationships * enable changing the target of a union without switching tables. Union * relationships are also marked as exclusive. */ FLECS_API extern const ecs_entity_t EcsUnion; /** Tag to indicate name identifier */ FLECS_API extern const ecs_entity_t EcsName; /** Tag to indicate symbol identifier */ FLECS_API extern const ecs_entity_t EcsSymbol; /** Tag to indicate alias identifier */ FLECS_API extern const ecs_entity_t EcsAlias; /** Used to express parent-child relationships. */ FLECS_API extern const ecs_entity_t EcsChildOf; /** Used to express inheritance relationships. */ FLECS_API extern const ecs_entity_t EcsIsA; /** Used to express dependency relationships */ FLECS_API extern const ecs_entity_t EcsDependsOn; /** Used to express a slot (used with prefab inheritance) */ FLECS_API extern const ecs_entity_t EcsSlotOf; /** Tag added to module entities */ FLECS_API extern const ecs_entity_t EcsModule; /** Tag to indicate an entity/component/system is private to a module */ FLECS_API extern const ecs_entity_t EcsPrivate; /** Tag added to prefab entities. Any entity with this tag is automatically * ignored by queries, unless EcsPrefab is explicitly queried for. */ FLECS_API extern const ecs_entity_t EcsPrefab; /** When this tag is added to an entity it is skipped by queries, unless * EcsDisabled is explicitly queried for. */ FLECS_API extern const ecs_entity_t EcsDisabled; /** Event that triggers when an id is added to an entity */ FLECS_API extern const ecs_entity_t EcsOnAdd; /** Event that triggers when an id is removed from an entity */ FLECS_API extern const ecs_entity_t EcsOnRemove; /** Event that triggers when a component is set for an entity */ FLECS_API extern const ecs_entity_t EcsOnSet; /** Event that triggers when a component is unset for an entity */ FLECS_API extern const ecs_entity_t EcsUnSet; /** Event that triggers observer when an entity starts/stops matching a query */ FLECS_API extern const ecs_entity_t EcsMonitor; /** Event that triggers when a table is created. */ FLECS_API extern const ecs_entity_t EcsOnTableCreate; /** Event that triggers when a table is deleted. */ FLECS_API extern const ecs_entity_t EcsOnTableDelete; /** Event that triggers when a table becomes empty (doesn't emit on creation). */ FLECS_API extern const ecs_entity_t EcsOnTableEmpty; /** Event that triggers when a table becomes non-empty. */ FLECS_API extern const ecs_entity_t EcsOnTableFill; /** Relationship used for specifying cleanup behavior. */ FLECS_API extern const ecs_entity_t EcsOnDelete; /** Relationship used to define what should happen when a target entity (second * element of a pair) is deleted. */ FLECS_API extern const ecs_entity_t EcsOnDeleteTarget; /** Remove cleanup policy. Must be used as target in pair with EcsOnDelete or * EcsOnDeleteTarget. */ FLECS_API extern const ecs_entity_t EcsRemove; /** Delete cleanup policy. Must be used as target in pair with EcsOnDelete or * EcsOnDeleteTarget. */ FLECS_API extern const ecs_entity_t EcsDelete; /** Panic cleanup policy. Must be used as target in pair with EcsOnDelete or * EcsOnDeleteTarget. */ FLECS_API extern const ecs_entity_t EcsPanic; /** Component that stores data for flattened relationships */ FLECS_API extern const ecs_entity_t ecs_id(EcsTarget); /** Tag added to root entity to indicate its subtree should be flattened. Used * together with assemblies. */ FLECS_API extern const ecs_entity_t EcsFlatten; /** Used like (EcsDefaultChildComponent, Component). When added to an entity, * this informs serialization formats which component to use when a value is * assigned to an entity without specifying the component. This is intended as * a hint, serialization formats are not required to use it. Adding this * component does not change the behavior of core ECS operations. */ FLECS_API extern const ecs_entity_t EcsDefaultChildComponent; /* Builtin predicates for comparing entity ids in queries. Only supported by rules */ FLECS_API extern const ecs_entity_t EcsPredEq; FLECS_API extern const ecs_entity_t EcsPredMatch; FLECS_API extern const ecs_entity_t EcsPredLookup; /* Builtin marker entities for opening/closing query scopes */ FLECS_API extern const ecs_entity_t EcsScopeOpen; FLECS_API extern const ecs_entity_t EcsScopeClose; /** Tag used to indicate query is empty */ FLECS_API extern const ecs_entity_t EcsEmpty; /* Pipeline module tags */ FLECS_API extern const ecs_entity_t ecs_id(EcsPipeline); FLECS_API extern const ecs_entity_t EcsOnStart; FLECS_API extern const ecs_entity_t EcsPreFrame; FLECS_API extern const ecs_entity_t EcsOnLoad; FLECS_API extern const ecs_entity_t EcsPostLoad; FLECS_API extern const ecs_entity_t EcsPreUpdate; FLECS_API extern const ecs_entity_t EcsOnUpdate; FLECS_API extern const ecs_entity_t EcsOnValidate; FLECS_API extern const ecs_entity_t EcsPostUpdate; FLECS_API extern const ecs_entity_t EcsPreStore; FLECS_API extern const ecs_entity_t EcsOnStore; FLECS_API extern const ecs_entity_t EcsPostFrame; FLECS_API extern const ecs_entity_t EcsPhase; /** Value used to quickly check if component is builtin. This is used to quickly * filter out tables with builtin components (for example for ecs_delete) */ #define EcsLastInternalComponentId (ecs_id(EcsPoly)) /** The first user-defined component starts from this id. Ids up to this number * are reserved for builtin components */ #define EcsFirstUserComponentId (8) /** The first user-defined entity starts from this id. Ids up to this number * are reserved for builtin entities */ #define EcsFirstUserEntityId (FLECS_HI_COMPONENT_ID + 128) /* When visualized the reserved id ranges look like this: * [1..8]: Builtin components * [9..FLECS_HI_COMPONENT_ID]: Low ids reserved for application components * [FLECS_HI_COMPONENT_ID + 1..EcsFirstUserEntityId]: Builtin entities */ /** @} */ /** @} */ /** * @defgroup world_api World * @brief Functions for working with `ecs_world_t`. * @{ */ /** * @defgroup world_creation_deletion Creation & Deletion * @{ */ /** Create a new world. * This operation automatically imports modules from addons Flecs has been built * with, except when the module specifies otherwise. * * @return A new world */ FLECS_API ecs_world_t* ecs_init(void); /** Create a new world with just the core module. * Same as ecs_init, but doesn't import modules from addons. This operation is * faster than ecs_init and results in less memory utilization. * * @return A new tiny world */ FLECS_API ecs_world_t* ecs_mini(void); /** Create a new world with arguments. * Same as ecs_init, but allows passing in command line arguments. Command line * arguments are used to: * - automatically derive the name of the application from argv[0] * * @return A new world */ FLECS_API ecs_world_t* ecs_init_w_args( int argc, char *argv[]); /** Delete a world. * This operation deletes the world, and everything it contains. * * @param world The world to delete. * @return Zero if successful, non-zero if failed. */ FLECS_API int ecs_fini( ecs_world_t *world); /** Returns whether the world is being deleted. * This operation can be used in callbacks like type hooks or observers to * detect if they are invoked while the world is being deleted. * * @param world The world. * @return True if being deleted, false if not. */ FLECS_API bool ecs_is_fini( const ecs_world_t *world); /** Register action to be executed when world is destroyed. * Fini actions are typically used when a module needs to clean up before a * world shuts down. * * @param world The world. * @param action The function to execute. * @param ctx Userdata to pass to the function */ FLECS_API void ecs_atfini( ecs_world_t *world, ecs_fini_action_t action, void *ctx); /** @} */ /** * @defgroup world_frame Frame functions * @{ */ /** Begin frame. * When an application does not use ecs_progress to control the main loop, it * can still use Flecs features such as FPS limiting and time measurements. This * operation needs to be invoked whenever a new frame is about to get processed. * * Calls to ecs_frame_begin must always be followed by ecs_frame_end. * * The function accepts a delta_time parameter, which will get passed to * systems. This value is also used to compute the amount of time the function * needs to sleep to ensure it does not exceed the target_fps, when it is set. * When 0 is provided for delta_time, the time will be measured. * * This function should only be ran from the main thread. * * @param world The world. * @param delta_time Time elapsed since the last frame. * @return The provided delta_time, or measured time if 0 was provided. */ FLECS_API ecs_ftime_t ecs_frame_begin( ecs_world_t *world, ecs_ftime_t delta_time); /** End frame. * This operation must be called at the end of the frame, and always after * ecs_frame_begin. * * @param world The world. */ FLECS_API void ecs_frame_end( ecs_world_t *world); /** Register action to be executed once after frame. * Post frame actions are typically used for calling operations that cannot be * invoked during iteration, such as changing the number of threads. * * @param world The world. * @param action The function to execute. * @param ctx Userdata to pass to the function */ FLECS_API void ecs_run_post_frame( ecs_world_t *world, ecs_fini_action_t action, void *ctx); /** Signal exit * This operation signals that the application should quit. It will cause * ecs_progress to return false. * * @param world The world to quit. */ FLECS_API void ecs_quit( ecs_world_t *world); /** Return whether a quit has been signaled. * * @param world The world. */ FLECS_API bool ecs_should_quit( const ecs_world_t *world); /** Measure frame time. * Frame time measurements measure the total time passed in a single frame, and * how much of that time was spent on systems and on merging. * * Frame time measurements add a small constant-time overhead to an application. * When an application sets a target FPS, frame time measurements are enabled by * default. * * @param world The world. * @param enable Whether to enable or disable frame time measuring. */ FLECS_API void ecs_measure_frame_time( ecs_world_t *world, bool enable); /** Measure system time. * System time measurements measure the time spent in each system. * * System time measurements add overhead to every system invocation and * therefore have a small but measurable impact on application performance. * System time measurements must be enabled before obtaining system statistics. * * @param world The world. * @param enable Whether to enable or disable system time measuring. */ FLECS_API void ecs_measure_system_time( ecs_world_t *world, bool enable); /** Set target frames per second (FPS) for application. * Setting the target FPS ensures that ecs_progress is not invoked faster than * the specified FPS. When enabled, ecs_progress tracks the time passed since * the last invocation, and sleeps the remaining time of the frame (if any). * * This feature ensures systems are ran at a consistent interval, as well as * conserving CPU time by not running systems more often than required. * * Note that ecs_progress only sleeps if there is time left in the frame. Both * time spent in flecs as time spent outside of flecs are taken into * account. * * @param world The world. * @param fps The target FPS. */ FLECS_API void ecs_set_target_fps( ecs_world_t *world, ecs_ftime_t fps); /** @} */ /** * @defgroup commands Commands * @{ */ /** Begin readonly mode. * Readonly mode guarantees that no mutations will occur on the world, which * makes the world safe to access from multiple threads. While the world is in * readonly mode, operations are deferred. * * Note that while similar to ecs_defer_begin, deferring only does not guarantee * the world is not mutated. Operations that are not deferred (like creating a * query) update data structures on the world and are allowed when deferring is * enabled, but not when the world is in readonly mode. * * A call to ecs_readonly_begin must be followed up with ecs_readonly_end. * * The ecs_progress() function automatically enables readonly mode while systems * are executed. * * When a world has more than one stage, the specific stage must be provided to * mutating ECS operations. Failing to do so will throw a readonly assert. A * world typically has more than one stage when using threads. An example: * * ecs_set_stage_count(world, 2); * ecs_stage_t *stage = ecs_get_stage(world, 1); * * ecs_readonly_begin(world); * ecs_add(world, e, Tag); // readonly assert * ecs_add(stage, e, Tag); // OK * * @param world The world * @return Whether world is in readonly mode. */ FLECS_API bool ecs_readonly_begin( ecs_world_t *world); /** End readonly mode. * This operation ends readonly mode, and must be called after * ecs_readonly_begin. Operations that were deferred while the world was in * readonly mode will be flushed. * * @param world The world */ FLECS_API void ecs_readonly_end( ecs_world_t *world); /** Merge world or stage. * When automatic merging is disabled, an application can call this * operation on either an individual stage, or on the world which will merge * all stages. This operation may only be called when staging is not enabled * (either after progress() or after readonly_end()). * * This operation may be called on an already merged stage or world. * * @param world The world. */ FLECS_API void ecs_merge( ecs_world_t *world); /** Defer operations until end of frame. * When this operation is invoked while iterating, operations inbetween the * defer_begin and defer_end operations are executed at the end of the frame. * * This operation is thread safe. * * @param world The world. * @return true if world changed from non-deferred mode to deferred mode. */ FLECS_API bool ecs_defer_begin( ecs_world_t *world); /** Test if deferring is enabled for current stage. * * @param world The world. * @return True if deferred, false if not. */ FLECS_API bool ecs_is_deferred( const ecs_world_t *world); /** End block of operations to defer. * See defer_begin. * * This operation is thread safe. * * @param world The world. * @return true if world changed from deferred mode to non-deferred mode. */ FLECS_API bool ecs_defer_end( ecs_world_t *world); /** Suspend deferring but do not flush queue. * This operation can be used to do an undeferred operation while not flushing * the operations in the queue. * * An application should invoke ecs_defer_resume before ecs_defer_end is called. * The operation may only be called when deferring is enabled. * * @param world The world. */ FLECS_API void ecs_defer_suspend( ecs_world_t *world); /** Resume deferring. * See ecs_defer_suspend. * * @param world The world. */ FLECS_API void ecs_defer_resume( ecs_world_t *world); /** Enable/disable automerging for world or stage. * When automerging is enabled, staged data will automatically be merged with * the world when staging ends. This happens at the end of progress(), at a * sync point or when readonly_end() is called. * * Applications can exercise more control over when data from a stage is merged * by disabling automerging. This requires an application to explicitly call * merge() on the stage. * * When this function is invoked on the world, it sets all current stages to * the provided value and sets the default for new stages. When this function is * invoked on a stage, automerging is only set for that specific stage. * * @param world The world. * @param automerge Whether to enable or disable automerging. */ FLECS_API void ecs_set_automerge( ecs_world_t *world, bool automerge); /** Configure world to have N stages. * This initializes N stages, which allows applications to defer operations to * multiple isolated defer queues. This is typically used for applications with * multiple threads, where each thread gets its own queue, and commands are * merged when threads are synchronized. * * Note that the ecs_set_threads function already creates the appropriate * number of stages. The set_stage_count() operation is useful for applications that * want to manage their own stages and/or threads. * * @param world The world. * @param stages The number of stages. */ FLECS_API void ecs_set_stage_count( ecs_world_t *world, int32_t stages); /** Get number of configured stages. * Return number of stages set by ecs_set_stage_count. * * @param world The world. * @return The number of stages used for threading. */ FLECS_API int32_t ecs_get_stage_count( const ecs_world_t *world); /** Get current stage id. * The stage id can be used by an application to learn about which stage it is * using, which typically corresponds with the worker thread id. * * @param world The world. * @return The stage id. */ FLECS_API int32_t ecs_get_stage_id( const ecs_world_t *world); /** Get stage-specific world pointer. * Flecs threads can safely invoke the API as long as they have a private * context to write to, also referred to as the stage. This function returns a * pointer to a stage, disguised as a world pointer. * * Note that this function does not(!) create a new world. It simply wraps the * existing world in a thread-specific context, which the API knows how to * unwrap. The reason the stage is returned as an ecs_world_t is so that it * can be passed transparently to the existing API functions, vs. having to * create a dediated API for threading. * * @param world The world. * @param stage_id The index of the stage to retrieve. * @return A thread-specific pointer to the world. */ FLECS_API ecs_world_t* ecs_get_stage( const ecs_world_t *world, int32_t stage_id); /** Test whether the current world is readonly. * This function allows the code to test whether the currently used world * is readonly or whether it allows for writing. * * @param world A pointer to a stage or the world. * @return True if the world or stage is readonly. */ FLECS_API bool ecs_stage_is_readonly( const ecs_world_t *world); /** Create asynchronous stage. * An asynchronous stage can be used to asynchronously queue operations for * later merging with the world. An asynchronous stage is similar to a regular * stage, except that it does not allow reading from the world. * * Asynchronous stages are never merged automatically, and must therefore be * manually merged with the ecs_merge function. It is not necessary to call * defer_begin or defer_end before and after enqueuing commands, as an * asynchronous stage unconditionally defers operations. * * The application must ensure that no commands are added to the stage while the * stage is being merged. * * An asynchronous stage must be cleaned up by ecs_async_stage_free. * * @param world The world. * @return The stage. */ FLECS_API ecs_world_t* ecs_async_stage_new( ecs_world_t *world); /** Free asynchronous stage. * The provided stage must be an asynchronous stage. If a non-asynchronous stage * is provided, the operation will fail. * * @param stage The stage to free. */ FLECS_API void ecs_async_stage_free( ecs_world_t *stage); /** Test whether provided stage is asynchronous. * * @param stage The stage. * @return True when the stage is asynchronous, false for a regular stage or * world. */ FLECS_API bool ecs_stage_is_async( ecs_world_t *stage); /** @} */ /** * @defgroup world_misc Misc * @{ */ /** Set a world context. * This operation allows an application to register custom data with a world * that can be accessed anywhere where the application has the world. * * @param world The world. * @param ctx A pointer to a user defined structure. * @param ctx_free A function that is invoked with ctx when the world is freed. */ FLECS_API void ecs_set_ctx( ecs_world_t *world, void *ctx, ecs_ctx_free_t ctx_free); /** Set a world binding context. * Same as ecs_set_ctx but for binding context. A binding context is intended * specifically for language bindings to store binding specific data. * * @param world The world. * @param ctx A pointer to a user defined structure. * @param ctx_free A function that is invoked with ctx when the world is freed. */ FLECS_API void ecs_set_binding_ctx( ecs_world_t *world, void *ctx, ecs_ctx_free_t ctx_free); /** Get the world context. * This operation retrieves a previously set world context. * * @param world The world. * @return The context set with ecs_set_ctx. If no context was set, the * function returns NULL. */ FLECS_API void* ecs_get_ctx( const ecs_world_t *world); /** Get the world binding context. * This operation retrieves a previously set world binding context. * * @param world The world. * @return The context set with ecs_set_binding_ctx. If no context was set, the * function returns NULL. */ FLECS_API void* ecs_get_binding_ctx( const ecs_world_t *world); /** Get world info. * * @param world The world. * @return Pointer to the world info. Valid for as long as the world exists. */ FLECS_API const ecs_world_info_t* ecs_get_world_info( const ecs_world_t *world); /** Dimension the world for a specified number of entities. * This operation will preallocate memory in the world for the specified number * of entities. Specifying a number lower than the current number of entities in * the world will have no effect. * * @param world The world. * @param entity_count The number of entities to preallocate. */ FLECS_API void ecs_dim( ecs_world_t *world, int32_t entity_count); /** Set a range for issueing new entity ids. * This function constrains the entity identifiers returned by ecs_new to the * specified range. This operation can be used to ensure that multiple processes * can run in the same simulation without requiring a central service that * coordinates issueing identifiers. * * If id_end is set to 0, the range is infinite. If id_end is set to a non-zero * value, it has to be larger than id_start. If id_end is set and ecs_new is * invoked after an id is issued that is equal to id_end, the application will * abort. * * @param world The world. * @param id_start The start of the range. * @param id_end The end of the range. */ FLECS_API void ecs_set_entity_range( ecs_world_t *world, ecs_entity_t id_start, ecs_entity_t id_end); /** Enable/disable range limits. * When an application is both a receiver of range-limited entities and a * producer of range-limited entities, range checking needs to be temporarily * disabled when inserting received entities. Range checking is disabled on a * stage, so setting this value is thread safe. * * @param world The world. * @param enable True if range checking should be enabled, false to disable. * @return The previous value. */ FLECS_API bool ecs_enable_range_check( ecs_world_t *world, bool enable); /** Get the largest issued entity id (not counting generation). * * @param world The world. */ FLECS_API ecs_entity_t ecs_get_max_id( const ecs_world_t *world); /** Force aperiodic actions. * The world may delay certain operations until they are necessary for the * application to function correctly. This may cause observable side effects * such as delayed triggering of events, which can be inconvenient when for * example running a test suite. * * The flags parameter specifies which aperiodic actions to run. Specify 0 to * run all actions. Supported flags start with 'EcsAperiodic'. Flags identify * internal mechanisms and may change unannounced. * * @param world The world. * @param flags The flags specifying which actions to run. */ FLECS_API void ecs_run_aperiodic( ecs_world_t *world, ecs_flags32_t flags); /** Cleanup empty tables. * This operation cleans up empty tables that meet certain conditions. Having * large amounts of empty tables does not negatively impact performance of the * ECS, but can take up considerable amounts of memory, especially in * applications with many components, and many components per entity. * * The generation specifies the minimum number of times this operation has * to be called before an empty table is cleaned up. If a table becomes non * empty, the generation is reset. * * The operation allows for both a "clear" generation and a "delete" * generation. When the clear generation is reached, the table's * resources are freed (like component arrays) but the table itself is not * deleted. When the delete generation is reached, the empty table is deleted. * * By specifying a non-zero id the cleanup logic can be limited to tables with * a specific (component) id. The operation will only increase the generation * count of matching tables. * * The min_id_count specifies a lower bound for the number of components a table * should have. Often the more components a table has, the more specific it is * and therefore less likely to be reused. * * The time budget specifies how long the operation should take at most. * * @param world The world. * @param id Optional component filter for the tables to evaluate. * @param clear_generation Free table data when generation > clear_generation. * @param delete_generation Delete table when generation > delete_generation. * @param min_id_count Minimum number of component ids the table should have. * @param time_budget_seconds Amount of time operation is allowed to spend. * @return Number of deleted tables. */ FLECS_API int32_t ecs_delete_empty_tables( ecs_world_t *world, ecs_id_t id, uint16_t clear_generation, uint16_t delete_generation, int32_t min_id_count, double time_budget_seconds); /** Get world from poly. * * @param poly A pointer to a poly object. * @return The world. */ FLECS_API const ecs_world_t* ecs_get_world( const ecs_poly_t *poly); /** Get entity from poly. * * @param poly A pointer to a poly object. * @return Entity associated with the poly object. */ FLECS_API ecs_entity_t ecs_get_entity( const ecs_poly_t *poly); /** Test if pointer is of specified type. * Usage: * ecs_poly_is(ptr, ecs_world_t) * * This operation only works for poly types. * * @param object The object to test. * @param type The id of the type. * @return True if the pointer is of the specified type. */ FLECS_API bool ecs_poly_is_( const ecs_poly_t *object, int32_t type); #define ecs_poly_is(object, type)\ ecs_poly_is_(object, type##_magic) /** Make a pair id. * This function is equivalent to using the ecs_pair macro, and is added for * convenience to make it easier for non C/C++ bindings to work with pairs. * * @param first The first element of the pair of the pair. * @param second The target of the pair. */ FLECS_API ecs_id_t ecs_make_pair( ecs_entity_t first, ecs_entity_t second); /** @} */ /** @} */ /** * @defgroup entities Entities * @brief Functions for working with `ecs_entity_t`. * @{ */ /** * @defgroup creating_entities Creating & Deleting * @brief Functions for creating and deleting entities. * @{ */ /** Create new entity id. * This operation returns an unused entity id. This operation is guaranteed to * return an empty entity as it does not use values set by ecs_set_scope or * ecs_set_with. * * @param world The world. * @return The new entity id. */ FLECS_API ecs_entity_t ecs_new_id( ecs_world_t *world); /** Create new low id. * This operation returns a new low id. Entity ids start after the * FLECS_HI_COMPONENT_ID constant. This reserves a range of low ids for things * like components, and allows parts of the code to optimize operations. * * Note that FLECS_HI_COMPONENT_ID does not represent the maximum number of * components that can be created, only the maximum number of components that * can take advantage of these optimizations. * * This operation is guaranteed to return an empty entity as it does not use * values set by ecs_set_scope or ecs_set_with. * * This operation does not recycle ids. * * @param world The world. * @return The new component id. */ FLECS_API ecs_entity_t ecs_new_low_id( ecs_world_t *world); /** Create new entity with (component) id. * This operation creates a new entity with an optional (component) id. When 0 * is passed to the id paramter, no component is added to the new entity. * * @param world The world. * @param id The component id to initialize the new entity with. * @return The new entity. */ FLECS_API ecs_entity_t ecs_new_w_id( ecs_world_t *world, ecs_id_t id); /** Create new entity in table. * This operation creates a new entity in the specified table. * * @param world The world. * @param table The table to which to add the new entity. * @return The new entity. */ FLECS_API ecs_entity_t ecs_new_w_table( ecs_world_t *world, ecs_table_t *table); /** Find or create an entity. * This operation creates a new entity, or modifies an existing one. When a name * is set in the ecs_entity_desc_t::name field and ecs_entity_desc_t::entity is * not set, the operation will first attempt to find an existing entity by that * name. If no entity with that name can be found, it will be created. * * If both a name and entity handle are provided, the operation will check if * the entity name matches with the provided name. If the names do not match, * the function will fail and return 0. * * If an id to a non-existing entity is provided, that entity id become alive. * * See the documentation of ecs_entity_desc_t for more details. * * @param world The world. * @param desc Entity init parameters. * @return A handle to the new or existing entity, or 0 if failed. */ FLECS_API ecs_entity_t ecs_entity_init( ecs_world_t *world, const ecs_entity_desc_t *desc); /** Bulk create/populate new entities. * This operation bulk inserts a list of new or predefined entities into a * single table. * * The operation does not take ownership of component arrays provided by the * application. Components that are non-trivially copyable will be moved into * the storage. * * The operation will emit OnAdd events for each added id, and OnSet events for * each component that has been set. * * If no entity ids are provided by the application, the returned array of ids * points to an internal datastructure which changes when new entities are * created/deleted. * * If as a result of the operation triggers are invoked that deletes * entities and no entity ids were provided by the application, the returned * array of identifiers may be incorrect. To avoid this problem, an application * can first call ecs_bulk_init to create empty entities, copy the array to one * that is owned by the application, and then use this array to populate the * entities. * * @param world The world. * @param desc Bulk creation parameters. * @return Array with the list of entity ids created/populated. */ FLECS_API const ecs_entity_t* ecs_bulk_init( ecs_world_t *world, const ecs_bulk_desc_t *desc); /** Create N new entities. * This operation is the same as ecs_new_w_id, but creates N entities * instead of one. * * @param world The world. * @param id The component id to create the entities with. * @param count The number of entities to create. * @return The first entity id of the newly created entities. */ FLECS_API const ecs_entity_t* ecs_bulk_new_w_id( ecs_world_t *world, ecs_id_t id, int32_t count); /** Clone an entity * This operation clones the components of one entity into another entity. If * no destination entity is provided, a new entity will be created. Component * values are not copied unless copy_value is true. * * @param world The world. * @param dst The entity to copy the components to. * @param src The entity to copy the components from. * @param copy_value If true, the value of components will be copied to dst. * @return The destination entity. */ FLECS_API ecs_entity_t ecs_clone( ecs_world_t *world, ecs_entity_t dst, ecs_entity_t src, bool copy_value); /** Delete an entity. * This operation will delete an entity and all of its components. The entity id * will be made available for recycling. If the entity passed to ecs_delete is * not alive, the operation will have no side effects. * * @param world The world. * @param entity The entity. */ FLECS_API void ecs_delete( ecs_world_t *world, ecs_entity_t entity); /** Delete all entities with the specified id. * This will delete all entities (tables) that have the specified id. The id * may be a wildcard and/or a pair. * * @param world The world. * @param id The id. */ FLECS_API void ecs_delete_with( ecs_world_t *world, ecs_id_t id); /** @} */ /** * @defgroup adding_removing Adding & Removing * @brief Functions for adding and removing components. * @{ */ /** Add a (component) id to an entity. * This operation adds a single (component) id to an entity. If the entity * already has the id, this operation will have no side effects. * * @param world The world. * @param entity The entity. * @param id The id to add. */ FLECS_API void ecs_add_id( ecs_world_t *world, ecs_entity_t entity, ecs_id_t id); /** Remove a (component) id from an entity. * This operation removes a single (component) id to an entity. If the entity * does not have the id, this operation will have no side effects. * * @param world The world. * @param entity The entity. * @param id The id to remove. */ FLECS_API void ecs_remove_id( ecs_world_t *world, ecs_entity_t entity, ecs_id_t id); /** Add override for (component) id. * Adding an override to an entity ensures that when the entity is instantiated * (by adding an IsA relationship to it) the component with the override is * copied to a component that is private to the instance. By default components * reachable through an IsA relationship are shared. * * Adding an override does not add the component. If an override is added to an * entity that does not have the component, it will still be added to the * instance, but with an uninitialized value (unless the component has a ctor). * When the entity does have the entity, the component of the instance will be * initialized with the value of the component on the entity. * * This is the same as what happens when calling ecs_add_id for an id that is * inherited (reachable through an IsA relationship). * * This operation is equivalent to doing: * ecs_add_id(world, entity, ECS_OVERRIDE | id); * * @param world The world. * @param entity The entity. * @param id The id to override. */ FLECS_API void ecs_override_id( ecs_world_t *world, ecs_entity_t entity, ecs_id_t id); /** Clear all components. * This operation will remove all components from an entity. * * @param world The world. * @param entity The entity. */ FLECS_API void ecs_clear( ecs_world_t *world, ecs_entity_t entity); /** Remove all instances of the specified (component) id. * This will remove the specified id from all entities (tables). The id may be * a wildcard and/or a pair. * * @param world The world. * @param id The id. */ FLECS_API void ecs_remove_all( ecs_world_t *world, ecs_id_t id); /** Set current with id. * New entities are automatically created with the specified id. * * @param world The world. * @param id The id. * @return The previous id. */ FLECS_API ecs_entity_t ecs_set_with( ecs_world_t *world, ecs_id_t id); /** Get current with id. * Get the id set with ecs_set_with. * * @param world The world. * @return The last id provided to ecs_set_with. */ FLECS_API ecs_id_t ecs_get_with( const ecs_world_t *world); /** @} */ /** * @defgroup enabling_disabling Enabling & Disabling * @brief Functions for enabling/disabling entities and components. * @{ */ /** Enable or disable entity. * This operation enables or disables an entity by adding or removing the * EcsDisabled tag. A disabled entity will not be matched with any systems, * unless the system explicitly specifies the EcsDisabled tag. * * @param world The world. * @param entity The entity to enable or disable. * @param enabled true to enable the entity, false to disable. */ FLECS_API void ecs_enable( ecs_world_t *world, ecs_entity_t entity, bool enabled); /** Enable or disable component. * Enabling or disabling a component does not add or remove a component from an * entity, but prevents it from being matched with queries. This operation can * be useful when a component must be temporarily disabled without destroying * its value. It is also a more performant operation for when an application * needs to add/remove components at high frequency, as enabling/disabling is * cheaper than a regular add or remove. * * @param world The world. * @param entity The entity. * @param id The component. * @param enable True to enable the component, false to disable. */ FLECS_API void ecs_enable_id( ecs_world_t *world, ecs_entity_t entity, ecs_id_t id, bool enable); /** Test if component is enabled. * Test whether a component is currently enabled or disabled. This operation * will return true when the entity has the component and if it has not been * disabled by ecs_enable_component. * * @param world The world. * @param entity The entity. * @param id The component. * @return True if the component is enabled, otherwise false. */ FLECS_API bool ecs_is_enabled_id( const ecs_world_t *world, ecs_entity_t entity, ecs_id_t id); /** @} */ /** * @defgroup getting Getting & Setting * @brief Functions for getting/setting components. * @{ */ /** Get an immutable pointer to a component. * This operation obtains a const pointer to the requested component. The * operation accepts the component entity id. * * @param world The world. * @param entity The entity. * @param id The id of the component to get. * @return The component pointer, NULL if the entity does not have the component. */ FLECS_API const void* ecs_get_id( const ecs_world_t *world, ecs_entity_t entity, ecs_id_t id); /** Create a component ref. * A ref is a handle to an entity + component which caches a small amount of * data to reduce overhead of repeatedly accessing the component. Use * ecs_ref_get to get the component data. * * @param world The world. * @param entity The entity. * @param id The id of the component. * @return The reference. */ FLECS_API ecs_ref_t ecs_ref_init_id( const ecs_world_t *world, ecs_entity_t entity, ecs_id_t id); /** Get component from ref. * Get component pointer from ref. The ref must be created with ecs_ref_init. * * @param world The world. * @param ref The ref. * @param id The component id. * @return The component pointer, NULL if the entity does not have the component. */ FLECS_API void* ecs_ref_get_id( const ecs_world_t *world, ecs_ref_t *ref, ecs_id_t id); /** Update ref. * Ensures contents of ref are up to date. Same as ecs_ref_get_id, but does not * return pointer to component id. * * @param world The world. * @param ref The ref. */ FLECS_API void ecs_ref_update( const ecs_world_t *world, ecs_ref_t *ref); /** Get a mutable pointer to a component. * This operation returns a mutable pointer to a component. If the component did * not yet exist, it will be added. * * If get_mut is called when the world is in deferred/readonly mode, the * function will: * - return a pointer to a temp storage if the component does not yet exist, or * - return a pointer to the existing component if it exists * * @param world The world. * @param entity The entity. * @param id The entity id of the component to obtain. * @return The component pointer. */ FLECS_API void* ecs_get_mut_id( ecs_world_t *world, ecs_entity_t entity, ecs_id_t id); /** Combines get_mut + modifed in single operation. * This operation is a more efficient alternative to calling ecs_get_mut_id and * ecs_modified_id separately. This operation is only valid when the world is in * deferred mode, which ensures that the Modified event is not emitted before * the modification takes place. * * @param world The world. * @param entity The entity. * @param id The id of the component to obtain. * @return The component pointer. */ FLECS_API void* ecs_get_mut_modified_id( ecs_world_t *world, ecs_entity_t entity, ecs_id_t id); /** Begin exclusive write access to entity. * This operation provides safe exclusive access to the components of an entity * without the overhead of deferring operations. * * When this operation is called simultaneously for the same entity more than * once it will throw an assert. Note that for this to happen, asserts must be * enabled. It is up to the application to ensure that access is exclusive, for * example by using a read-write mutex. * * Exclusive access is enforced at the table level, so only one entity can be * exclusively accessed per table. The exclusive access check is thread safe. * * This operation must be followed up with ecs_write_end. * * @param world The world. * @param entity The entity. * @return A record to the entity. */ FLECS_API ecs_record_t* ecs_write_begin( ecs_world_t *world, ecs_entity_t entity); /** End exclusive write access to entity. * This operation ends exclusive access, and must be called after * ecs_write_begin. * * @param record Record to the entity. */ FLECS_API void ecs_write_end( ecs_record_t *record); /** Begin read access to entity. * This operation provides safe read access to the components of an entity. * Multiple simultaneous reads are allowed per entity. * * This operation ensures that code attempting to mutate the entity's table will * throw an assert. Note that for this to happen, asserts must be enabled. It is * up to the application to ensure that this does not happen, for example by * using a read-write mutex. * * This operation does *not* provide the same guarantees as a read-write mutex, * as it is possible to call ecs_read_begin after calling ecs_write_begin. It is * up to application has to ensure that this does not happen. * * This operation must be followed up with ecs_read_end. * * @param world The world. * @param entity The entity. * @return A record to the entity. */ FLECS_API const ecs_record_t* ecs_read_begin( ecs_world_t *world, ecs_entity_t entity); /** End read access to entity. * This operation ends read access, and must be called after ecs_read_begin. * * @param record Record to the entity. */ FLECS_API void ecs_read_end( const ecs_record_t *record); /** Get entity corresponding with record. * This operation only works for entities that are not empty. * * @param record The record for which to obtain the entity id. */ FLECS_API ecs_entity_t ecs_record_get_entity( const ecs_record_t *record); /** Get component from entity record. * This operation returns a pointer to a component for the entity * associated with the provided record. For safe access to the component, obtain * the record with ecs_read_begin or ecs_write_begin. * * Obtaining a component from a record is faster than obtaining it from the * entity handle, as it reduces the number of lookups required. * * @param world The world. * @param record Record to the entity. * @param id The (component) id. * @return Pointer to component, or NULL if entity does not have the component. */ FLECS_API const void* ecs_record_get_id( ecs_world_t *world, const ecs_record_t *record, ecs_id_t id); /** Same as ecs_record_get_id, but returns a mutable pointer. * For safe access to the component, obtain the record with ecs_write_begin. * * @param world The world. * @param record Record to the entity. * @param id The (component) id. * @return Pointer to component, or NULL if entity does not have the component. */ FLECS_API void* ecs_record_get_mut_id( ecs_world_t *world, ecs_record_t *record, ecs_id_t id); /** Test if entity for record has component. * * @param world The world. * @param record Record to the entity. * @param id The (component) id. */ FLECS_API bool ecs_record_has_id( ecs_world_t *world, const ecs_record_t *record, ecs_id_t id); /** Emplace a component. * Emplace is similar to get_mut except that the component constructor is not * invoked for the returned pointer, allowing the component to be "constructed" * directly in the storage. * * Emplace can only be used if the entity does not yet have the component. If * the entity has the component, the operation will fail. * * @param world The world. * @param entity The entity. * @param id The component to obtain. * @return The (uninitialized) component pointer. */ FLECS_API void* ecs_emplace_id( ecs_world_t *world, ecs_entity_t entity, ecs_id_t id); /** Signal that a component has been modified. * This operation is usually used after modifying a component value obtained by * ecs_get_mut_id. The operation will mark the component as dirty, and invoke * OnSet observers and hooks. * * @param world The world. * @param entity The entity. * @param id The id of the component that was modified. */ FLECS_API void ecs_modified_id( ecs_world_t *world, ecs_entity_t entity, ecs_id_t id); /** Set the value of a component. * This operation allows an application to set the value of a component. The * operation is equivalent to calling ecs_get_mut_id followed by * ecs_modified_id. The operation will not modify the value of the passed in * component. If the component has a copy hook registered, it will be used to * copy in the component. * * If the provided entity is 0, a new entity will be created. * * @param world The world. * @param entity The entity. * @param id The id of the component to set. * @param size The size of the pointed-to value. * @param ptr The pointer to the value. * @return The entity. A new entity if no entity was provided. */ FLECS_API ecs_entity_t ecs_set_id( ecs_world_t *world, ecs_entity_t entity, ecs_id_t id, size_t size, const void *ptr); /** @} */ /** * @defgroup liveliness Entity Liveliness * @brief Functions for testing and modifying entity liveliness. * @{ */ /** Test whether an entity is valid. * Entities that are valid can be used with API functions. Using invalid * entities with API operations will cause the function to panic. * * An entity is valid if it is not 0 and if it is alive. * * is_valid will return true for ids that don't exist (alive or not alive). This * allows for using ids that have never been created by ecs_new or similar. In * this the function differs from ecs_is_alive, which will return false for * entities that do not yet exist. * * The operation will return false for an id that exists and is not alive, as * using this id with an API operation would cause it to assert. * * @param world The world. * @param e The entity. * @return True if the entity is valid, false if the entity is not valid. */ FLECS_API bool ecs_is_valid( const ecs_world_t *world, ecs_entity_t e); /** Test whether an entity is alive. * Entities are alive after they are created, and become not alive when they are * deleted. Operations that return alive ids are (amongst others) ecs_new_id, * ecs_new_low_id and ecs_entity_init. Ids can be made alive with the ecs_ensure * function. * * After an id is deleted it can be recycled. Recycled ids are different from * the original id in that they have a different generation count. This makes it * possible for the API to distinguish between the two. An example: * * ecs_entity_t e1 = ecs_new_id(world); * ecs_is_alive(world, e1); // true * ecs_delete(world, e1); * ecs_is_alive(world, e1); // false * * ecs_entity_t e2 = ecs_new_id(world); // recycles e1 * ecs_is_alive(world, e2); // true * ecs_is_alive(world, e1); // false * * @param world The world. * @param e The entity. * @return True if the entity is alive, false if the entity is not alive. */ FLECS_API bool ecs_is_alive( const ecs_world_t *world, ecs_entity_t e); /** Remove generation from entity id. * * @param e The entity id. * @return The entity id without the generation count. */ FLECS_API ecs_id_t ecs_strip_generation( ecs_entity_t e); /** Override the generation of an entity. * The generation count of an entity is increased each time an entity is deleted * and is used to test whether an entity id is alive. * * This operation overrides the current generation of an entity with the * specified generation, which can be useful if an entity is externally managed, * like for external pools, savefiles or netcode. * * @param world The world. * @param entity Entity for which to set the generation with the new generation. */ FLECS_API void ecs_set_entity_generation( ecs_world_t *world, ecs_entity_t entity); /** Get alive identifier. * In some cases an application may need to work with identifiers from which * the generation has been stripped. A typical scenario in which this happens is * when iterating relationships in an entity type. * * For example, when obtaining the parent id from a ChildOf relationship, the parent * (second element of the pair) will have been stored in a 32 bit value, which * cannot store the entity generation. This function can retrieve the identifier * with the current generation for that id. * * If the provided identifier is not alive, the function will return 0. * * @param world The world. * @param e The for which to obtain the current alive entity id. * @return The alive entity id if there is one, or 0 if the id is not alive. */ FLECS_API ecs_entity_t ecs_get_alive( const ecs_world_t *world, ecs_entity_t e); /** Ensure id is alive. * This operation ensures that the provided id is alive. This is useful in * scenarios where an application has an existing id that has not been created * with ecs_new (such as a global constant or an id from a remote application). * * When this operation is successful it guarantees that the provided id exists, * is valid and is alive. * * Before this operation the id must either not be alive or have a generation * that is equal to the passed in entity. * * If the provided id has a non-zero generation count and the id does not exist * in the world, the id will be created with the specified generation. * * If the provided id is alive and has a generation count that does not match * the provided id, the operation will fail. * * @param world The world. * @param entity The entity id to make alive. */ FLECS_API void ecs_ensure( ecs_world_t *world, ecs_entity_t entity); /** Same as ecs_ensure, but for (component) ids. * An id can be an entity or pair, and can contain id flags. This operation * ensures that the entity (or entities, for a pair) are alive. * * When this operation is successful it guarantees that the provided id can be * used in operations that accept an id. * * Since entities in a pair do not encode their generation ids, this operation * will not fail when an entity with non-zero generation count already exists in * the world. * * This is different from ecs_ensure, which will fail if attempted with an id * that has generation 0 and an entity with a non-zero generation is currently * alive. * * @param world The world. * @param id The id to make alive. */ FLECS_API void ecs_ensure_id( ecs_world_t *world, ecs_id_t id); /** Test whether an entity exists. * Similar as ecs_is_alive, but ignores entity generation count. * * @param world The world. * @param entity The entity. * @return True if the entity exists, false if the entity does not exist. */ FLECS_API bool ecs_exists( const ecs_world_t *world, ecs_entity_t entity); /** @} */ /** * @defgroup entity_info Entity Information. * @brief Get information from entity. * @{ */ /** Get the type of an entity. * * @param world The world. * @param entity The entity. * @return The type of the entity, NULL if the entity has no components. */ FLECS_API const ecs_type_t* ecs_get_type( const ecs_world_t *world, ecs_entity_t entity); /** Get the table of an entity. * * @param world The world. * @param entity The entity. * @return The table of the entity, NULL if the entity has no components/tags. */ FLECS_API ecs_table_t* ecs_get_table( const ecs_world_t *world, ecs_entity_t entity); /** Convert type to string. * The result of this operation must be freed with ecs_os_free. * * @param world The world. * @param type The type. * @return The stringified type. */ FLECS_API char* ecs_type_str( const ecs_world_t *world, const ecs_type_t* type); /** Convert table to string. * Same as ecs_type_str(world, ecs_table_get_type(table)). The result of this * operation must be freed with ecs_os_free. * * @param world The world. * @param table The table. * @return The stringified table type. */ FLECS_API char* ecs_table_str( const ecs_world_t *world, const ecs_table_t *table); /** Convert entity to string. * Same as combining: * - ecs_get_fullpath(world, entity) * - ecs_type_str(world, ecs_get_type(world, entity)) * * The result of this operation must be freed with ecs_os_free. * * @param world The world. * @param entity The entity. * @return The entity path with stringified type. */ FLECS_API char* ecs_entity_str( const ecs_world_t *world, ecs_entity_t entity); /** Test if an entity has an id. * This operation returns true if the entity has or inherits the specified id. * * @param world The world. * @param entity The entity. * @param id The id to test for. * @return True if the entity has the id, false if not. */ FLECS_API bool ecs_has_id( const ecs_world_t *world, ecs_entity_t entity, ecs_id_t id); /** Test if an entity owns an id. * This operation returns true if the entity has the specified id. The operation * behaves the same as ecs_has_id, except that it will return false for * components that are inherited through an IsA relationship. * * @param world The world. * @param entity The entity. * @param id The id to test for. * @return True if the entity has the id, false if not. */ FLECS_API bool ecs_owns_id( const ecs_world_t *world, ecs_entity_t entity, ecs_id_t id); /** Get the target of a relationship. * This will return a target (second element of a pair) of the entity for the * specified relationship. The index allows for iterating through the targets, * if a single entity has multiple targets for the same relationship. * * If the index is larger than the total number of instances the entity has for * the relationship, the operation will return 0. * * @param world The world. * @param entity The entity. * @param rel The relationship between the entity and the target. * @param index The index of the relationship instance. * @return The target for the relationship at the specified index. */ FLECS_API ecs_entity_t ecs_get_target( const ecs_world_t *world, ecs_entity_t entity, ecs_entity_t rel, int32_t index); /** Get parent (target of ChildOf relationship) for entity. * This operation is the same as calling: * ecs_get_target(world, entity, EcsChildOf, 0); * * @param world The world. * @param entity The entity. * @return The parent of the entity, 0 if the entity has no parent. */ FLECS_API ecs_entity_t ecs_get_parent( const ecs_world_t *world, ecs_entity_t entity); /** Get the target of a relationship for a given id. * This operation returns the first entity that has the provided id by following * the specified relationship. If the entity itself has the id then entity will * be returned. If the id cannot be found on the entity or by following the * relationship, the operation will return 0. * * This operation can be used to lookup, for example, which prefab is providing * a component by specifying the IsA relationship: * * // Is Position provided by the entity or one of its base entities? * ecs_get_target_for_id(world, entity, EcsIsA, ecs_id(Position)) * * @param world The world. * @param entity The entity. * @param rel The relationship to follow. * @param id The id to lookup. * @return The entity for which the target has been found. */ FLECS_API ecs_entity_t ecs_get_target_for_id( const ecs_world_t *world, ecs_entity_t entity, ecs_entity_t rel, ecs_id_t id); /** Return depth for entity in tree for the specified relationship. * Depth is determined by counting the number of targets encountered while * traversing up the relationship tree for rel. Only acyclic relationships are * supported. * * @param world The world. * @param entity The entity. * @param rel The relationship. * @return The depth of the entity in the tree. */ FLECS_API int32_t ecs_get_depth( const ecs_world_t *world, ecs_entity_t entity, ecs_entity_t rel); typedef struct ecs_flatten_desc_t { /* When true, the flatten operation will not remove names from entities in * the flattened tree. This may fail if entities from different subtrees * have the same name. */ bool keep_names; /* When true, the flattened tree won't contain information about the * original depth of the entities. This can reduce fragmentation, but may * cause existing code, such as cascade queries, to no longer work. */ bool lose_depth; } ecs_flatten_desc_t; /** Recursively flatten relationship for target entity (experimental). * This operation combines entities in the subtree of the specified pair from * different parents in the same table. This can reduce memory fragmentation * and reduces the number of tables in the storage, which improves RAM * utilization and various other operations, such as entity cleanup. * * The lifecycle of entities in a fixed subtree are bound to the specified * parent. Entities in a fixed subtree cannot be deleted individually. Entities * can also not change the target of the fixed relationship, which includes * removing the relationship. * * Entities in a fixed subtree are still fragmented on subtree depth. This * ensures that entities can still be iterated in breadth-first order with the * cascade query modifier. * * The current implementation is limited to exclusive acyclic relationships, and * does not allow for adding/removing to entities in flattened tables. An entity * may only be flattened for a single relationship. Future iterations of the * feature may remove these limitations. * * @param world The world. * @param pair The relationship pair from which to start flattening. * @param desc Options for flattening the tree. */ FLECS_API void ecs_flatten( ecs_world_t *world, ecs_id_t pair, const ecs_flatten_desc_t *desc); /** Count entities that have the specified id. * Returns the number of entities that have the specified id. * * @param world The world. * @param entity The id to search for. * @return The number of entities that have the id. */ FLECS_API int32_t ecs_count_id( const ecs_world_t *world, ecs_id_t entity); /** @} */ /** * @defgroup paths Entity Names * @brief Functions for working with entity names and paths. * @{ */ /** Get the name of an entity. * This will return the name stored in (EcsIdentifier, EcsName). * * @param world The world. * @param entity The entity. * @return The type of the entity, NULL if the entity has no name. */ FLECS_API const char* ecs_get_name( const ecs_world_t *world, ecs_entity_t entity); /** Get the symbol of an entity. * This will return the symbol stored in (EcsIdentifier, EcsSymbol). * * @param world The world. * @param entity The entity. * @return The type of the entity, NULL if the entity has no name. */ FLECS_API const char* ecs_get_symbol( const ecs_world_t *world, ecs_entity_t entity); /** Set the name of an entity. * This will set or overwrite the name of an entity. If no entity is provided, * a new entity will be created. * * The name is stored in (EcsIdentifier, EcsName). * * @param world The world. * @param entity The entity. * @param name The name. * @return The provided entity, or a new entity if 0 was provided. */ FLECS_API ecs_entity_t ecs_set_name( ecs_world_t *world, ecs_entity_t entity, const char *name); /** Set the symbol of an entity. * This will set or overwrite the symbol of an entity. If no entity is provided, * a new entity will be created. * * The symbol is stored in (EcsIdentifier, EcsSymbol). * * @param world The world. * @param entity The entity. * @param symbol The symbol. * @return The provided entity, or a new entity if 0 was provided. */ FLECS_API ecs_entity_t ecs_set_symbol( ecs_world_t *world, ecs_entity_t entity, const char *symbol); /** Set alias for entity. * An entity can be looked up using its alias from the root scope without * providing the fully qualified name if its parent. An entity can only have * a single alias. * * The symbol is stored in (EcsIdentifier, EcsAlias). * * @param world The world. * @param entity The entity. * @param alias The alias. */ FLECS_API void ecs_set_alias( ecs_world_t *world, ecs_entity_t entity, const char *alias); /** Lookup an entity by name. * Returns an entity that matches the specified name. Only looks for entities in * the current scope (root if no scope is provided). * * @param world The world. * @param name The entity name. * @return The entity with the specified name, or 0 if no entity was found. */ FLECS_API ecs_entity_t ecs_lookup( const ecs_world_t *world, const char *name); /** Lookup a child entity by name. * Returns an entity that matches the specified name. Only looks for entities in * the provided parent. If no parent is provided, look in the current scope ( * root if no scope is provided). * * @param world The world. * @param name The entity name. * @return The entity with the specified name, or 0 if no entity was found. */ FLECS_API ecs_entity_t ecs_lookup_child( const ecs_world_t *world, ecs_entity_t parent, const char *name); /** Lookup an entity from a path. * Lookup an entity from a provided path, relative to the provided parent. The * operation will use the provided separator to tokenize the path expression. If * the provided path contains the prefix, the search will start from the root. * * If the entity is not found in the provided parent, the operation will * continue to search in the parent of the parent, until the root is reached. If * the entity is still not found, the lookup will search in the flecs.core * scope. If the entity is not found there either, the function returns 0. * * @param world The world. * @param parent The entity from which to resolve the path. * @param path The path to resolve. * @param sep The path separator. * @param prefix The path prefix. * @param recursive Recursively traverse up the tree until entity is found. * @return The entity if found, else 0. */ FLECS_API ecs_entity_t ecs_lookup_path_w_sep( const ecs_world_t *world, ecs_entity_t parent, const char *path, const char *sep, const char *prefix, bool recursive); /** Lookup an entity by its symbol name. * This looks up an entity by symbol stored in (EcsIdentifier, EcsSymbol). The * operation does not take into account hierarchies. * * This operation can be useful to resolve, for example, a type by its C * identifier, which does not include the Flecs namespacing. * * @param world The world. * @param symbol The symbol. * @param lookup_as_path If not found as a symbol, lookup as path. * @param recursive If looking up as path, recursively traverse up the tree. * @return The entity if found, else 0. */ FLECS_API ecs_entity_t ecs_lookup_symbol( const ecs_world_t *world, const char *symbol, bool lookup_as_path, bool recursive); /** Get a path identifier for an entity. * This operation creates a path that contains the names of the entities from * the specified parent to the provided entity, separated by the provided * separator. If no parent is provided the path will be relative to the root. If * a prefix is provided, the path will be prefixed by the prefix. * * If the parent is equal to the provided child, the operation will return an * empty string. If a nonzero component is provided, the path will be created by * looking for parents with that component. * * The returned path should be freed by the application. * * @param world The world. * @param parent The entity from which to create the path. * @param child The entity to which to create the path. * @param sep The separator to use between path elements. * @param prefix The initial character to use for root elements. * @return The relative entity path. */ FLECS_API char* ecs_get_path_w_sep( const ecs_world_t *world, ecs_entity_t parent, ecs_entity_t child, const char *sep, const char *prefix); /** Write path identifier to buffer. * Same as ecs_get_path_w_sep, but writes result to an ecs_strbuf_t. * * @param world The world. * @param parent The entity from which to create the path. * @param child The entity to which to create the path. * @param sep The separator to use between path elements. * @param prefix The initial character to use for root elements. * @param buf The buffer to write to. */ void ecs_get_path_w_sep_buf( const ecs_world_t *world, ecs_entity_t parent, ecs_entity_t child, const char *sep, const char *prefix, ecs_strbuf_t *buf); /** Find or create entity from path. * This operation will find or create an entity from a path, and will create any * intermediate entities if required. If the entity already exists, no entities * will be created. * * If the path starts with the prefix, then the entity will be created from the * root scope. * * @param world The world. * @param parent The entity relative to which the entity should be created. * @param path The path to create the entity for. * @param sep The separator used in the path. * @param prefix The prefix used in the path. * @return The entity. */ FLECS_API ecs_entity_t ecs_new_from_path_w_sep( ecs_world_t *world, ecs_entity_t parent, const char *path, const char *sep, const char *prefix); /** Add specified path to entity. * This operation is similar to ecs_new_from_path, but will instead add the path * to an existing entity. * * If an entity already exists for the path, it will be returned instead. * * @param world The world. * @param entity The entity to which to add the path. * @param parent The entity relative to which the entity should be created. * @param path The path to create the entity for. * @param sep The separator used in the path. * @param prefix The prefix used in the path. * @return The entity. */ FLECS_API ecs_entity_t ecs_add_path_w_sep( ecs_world_t *world, ecs_entity_t entity, ecs_entity_t parent, const char *path, const char *sep, const char *prefix); /** Set the current scope. * This operation sets the scope of the current stage to the provided entity. * As a result new entities will be created in this scope, and lookups will be * relative to the provided scope. * * It is considered good practice to restore the scope to the old value. * * @param world The world. * @param scope The entity to use as scope. * @return The previous scope. */ FLECS_API ecs_entity_t ecs_set_scope( ecs_world_t *world, ecs_entity_t scope); /** Get the current scope. * Get the scope set by ecs_set_scope. If no scope is set, this operation will * return 0. * * @param world The world. * @return The current scope. */ FLECS_API ecs_entity_t ecs_get_scope( const ecs_world_t *world); /** Set a name prefix for newly created entities. * This is a utility that lets C modules use prefixed names for C types and * C functions, while using names for the entity names that do not have the * prefix. The name prefix is currently only used by ECS_COMPONENT. * * @param world The world. * @param prefix The name prefix to use. * @return The previous prefix. */ FLECS_API const char* ecs_set_name_prefix( ecs_world_t *world, const char *prefix); /** Set search path for lookup operations. * This operation accepts an array of entity ids that will be used as search * scopes by lookup operations. The operation returns the current search path. * It is good practice to restore the old search path. * * The search path will be evaluated starting from the last element. * * The default search path includes flecs.core. When a custom search path is * provided it overwrites the existing search path. Operations that rely on * looking up names from flecs.core without providing the namespace may fail if * the custom search path does not include flecs.core (EcsFlecsCore). * * The search path array is not copied into managed memory. The application must * ensure that the provided array is valid for as long as it is used as the * search path. * * The provided array must be terminated with a 0 element. This enables an * application to push/pop elements to an existing array without invoking the * ecs_set_lookup_path operation again. * * @param world The world. * @param lookup_path 0-terminated array with entity ids for the lookup path. * @return Current lookup path array. */ FLECS_API ecs_entity_t* ecs_set_lookup_path( ecs_world_t *world, const ecs_entity_t *lookup_path); /** Get current lookup path. * Returns value set by ecs_set_lookup_path. * * @param world The world. * @return The current lookup path. */ FLECS_API ecs_entity_t* ecs_get_lookup_path( const ecs_world_t *world); /** @} */ /** @} */ /** * @defgroup components Components * @brief Functions for registering and working with components. * @{ */ /** Find or create a component. * This operation creates a new component, or finds an existing one. The find or * create behavior is the same as ecs_entity_init. * * When an existing component is found, the size and alignment are verified with * the provided values. If the values do not match, the operation will fail. * * See the documentation of ecs_component_desc_t for more details. * * @param world The world. * @param desc Component init parameters. * @return A handle to the new or existing component, or 0 if failed. */ FLECS_API ecs_entity_t ecs_component_init( ecs_world_t *world, const ecs_component_desc_t *desc); /** Get the type for an id. * This function returnsthe type information for an id. The specified id can be * any valid id. For the rules on how type information is determined based on * id, see ecs_get_typeid. * * @param world The world. * @param id The id. * @return The type information of the id. */ FLECS_API const ecs_type_info_t* ecs_get_type_info( const ecs_world_t *world, ecs_id_t id); /** Register hooks for component. * Hooks allow for the execution of user code when components are constructed, * copied, moved, destructed, added, removed or set. Hooks can be assigned as * as long as a component has not yet been used (added to an entity). * * The hooks that are currently set can be accessed with ecs_get_type_info. * * @param world The world. * @param id The component id for which to register the actions * @param hooks Type that contains the component actions. */ FLECS_API void ecs_set_hooks_id( ecs_world_t *world, ecs_entity_t id, const ecs_type_hooks_t *hooks); /** Get hooks for component. * * @param world The world. * @param id The component id for which to retrieve the hooks. * @return The hooks for the component, or NULL if not registered. */ FLECS_API const ecs_type_hooks_t* ecs_get_hooks_id( ecs_world_t *world, ecs_entity_t id); /** @} */ /** * @defgroup ids Ids * @brief Functions for working with `ecs_id_t`. * @{ */ /** Returns whether specified id a tag. * This operation returns whether the specified type is a tag (a component * without data/size). * * An id is a tag when: * - it is an entity without the EcsComponent component * - it has an EcsComponent with size member set to 0 * - it is a pair where both elements are a tag * - it is a pair where the first element has the EcsTag tag * * @param world The world. * @param id The id. * @return Whether the provided id is a tag. */ FLECS_API bool ecs_id_is_tag( const ecs_world_t *world, ecs_id_t id); /** Return whether represents a union. * This operation returns whether the specified type represents a union. Only * pair ids can be unions. * * An id represents a union when: * - The first element of the pair is EcsUnion/flecs::Union * - The first element of the pair has EcsUnion/flecs::Union * * @param world The world. * @param id The id. * @return Whether the provided id represents a union. */ FLECS_API bool ecs_id_is_union( const ecs_world_t *world, ecs_id_t id); /** Returns whether specified id is in use. * This operation returns whether an id is in use in the world. An id is in use * if it has been added to one or more tables. * * @param world The world. * @param id The id. * @return Whether the id is in use. */ FLECS_API bool ecs_id_in_use( const ecs_world_t *world, ecs_id_t id); /** Get the type for an id. * This operation returns the component id for an id, if the id is associated * with a type. For a regular component with a non-zero size (an entity with the * EcsComponent component) the operation will return the entity itself. * * For an entity that does not have the EcsComponent component, or with an * EcsComponent value with size 0, the operation will return 0. * * For a pair id the operation will return the type associated with the pair, by * applying the following rules in order: * - The first pair element is returned if it is a component * - 0 is returned if the relationship entity has the Tag property * - The second pair element is returned if it is a component * - 0 is returned. * * @param world The world. * @param id The id. * @return The type id of the id. */ FLECS_API ecs_entity_t ecs_get_typeid( const ecs_world_t *world, ecs_id_t id); /** Utility to match an id with a pattern. * This operation returns true if the provided pattern matches the provided * id. The pattern may contain a wildcard (or wildcards, when a pair). * * @param id The id. * @param pattern The pattern to compare with. */ FLECS_API bool ecs_id_match( ecs_id_t id, ecs_id_t pattern); /** Utility to check if id is a pair. * * @param id The id. * @return True if id is a pair. */ FLECS_API bool ecs_id_is_pair( ecs_id_t id); /** Utility to check if id is a wildcard. * * @param id The id. * @return True if id is a wildcard or a pair containing a wildcard. */ FLECS_API bool ecs_id_is_wildcard( ecs_id_t id); /** Utility to check if id is valid. * A valid id is an id that can be added to an entity. Invalid ids are: * - ids that contain wildcards * - ids that contain invalid entities * - ids that are 0 or contain 0 entities * * Note that the same rules apply to removing from an entity, with the exception * of wildcards. * * @param world The world. * @param id The id. * @return True if the id is valid. */ FLECS_API bool ecs_id_is_valid( const ecs_world_t *world, ecs_id_t id); /** Get flags associated with id. * This operation returns the internal flags (see api_flags.h) that are * associated with the provided id. * * @param world The world. * @param id The id. * @return Flags associated with the id, or 0 if the id is not in use. */ FLECS_API ecs_flags32_t ecs_id_get_flags( const ecs_world_t *world, ecs_id_t id); /** Convert id flag to string. * This operation converts a id flag to a string. * * @param id_flags The id flag. * @return The id flag string, or NULL if no valid id is provided. */ FLECS_API const char* ecs_id_flag_str( ecs_id_t id_flags); /** Convert id to string. * This operation interprets the structure of an id and converts it to a string. * * @param world The world. * @param id The id to convert to a string. * @return The id converted to a string. */ FLECS_API char* ecs_id_str( const ecs_world_t *world, ecs_id_t id); /** Write id string to buffer. * Same as ecs_id_str but writes result to ecs_strbuf_t. * * @param world The world. * @param id The id to convert to a string. * @param buf The buffer to write to. */ FLECS_API void ecs_id_str_buf( const ecs_world_t *world, ecs_id_t id, ecs_strbuf_t *buf); /** @} */ /** * @defgroup filters Filters * @brief Functions for working with `ecs_term_t` and `ecs_filter_t`. * @{ */ /** Iterator for a single (component) id. * A term iterator returns all entities (tables) that match a single (component) * id. The search for the matching set of entities (tables) is performed in * constant time. * * @param world The world. * @param term The term. * @return The iterator. */ FLECS_API ecs_iter_t ecs_term_iter( const ecs_world_t *world, ecs_term_t *term); /** Return a chained term iterator. * A chained iterator applies a filter to the results of the input iterator. The * resulting iterator must be iterated with ecs_term_next. * * @param it The input iterator * @param term The term filter to apply to the iterator. * @return The chained iterator. */ FLECS_API ecs_iter_t ecs_term_chain_iter( const ecs_iter_t *it, ecs_term_t *term); /** Progress a term iterator. * This operation progresses the term iterator to the next table. The * iterator must have been initialized with `ecs_term_iter`. This operation * must be invoked at least once before interpreting the contents of the * iterator. * * @param it The iterator. * @returns True if more data is available, false if not. */ FLECS_API bool ecs_term_next( ecs_iter_t *it); /** Iterator for a parent's children. * This operation is equivalent to a term iterator for (ChildOf, parent). * Iterate the result with ecs_children_next. * * @param world The world. * @param parent The parent for which to iterate the children. * @return The iterator. */ FLECS_API ecs_iter_t ecs_children( const ecs_world_t *world, ecs_entity_t parent); /** Progress a children iterator. * Equivalent to ecs_term_next. * * @param it The iterator. * @returns True if more data is available, false if not. */ FLECS_API bool ecs_children_next( ecs_iter_t *it); /** Test whether term id is set. * * @param id The term id. * @return True when set, false when not set. */ FLECS_API bool ecs_term_id_is_set( const ecs_term_id_t *id); /** Test whether a term is set. * This operation can be used to test whether a term has been initialized with * values or whether it is empty. * * An application generally does not need to invoke this operation. It is useful * when initializing a 0-initialized array of terms (like in ecs_term_desc_t) as * this operation can be used to find the last initialized element. * * @param term The term. * @return True when set, false when not set. */ FLECS_API bool ecs_term_is_initialized( const ecs_term_t *term); /** Is term matched on $this variable. * This operation checks whether a term is matched on the $this variable, which * is the default source for queries. * * A term has a $this source when: * - ecs_term_t::src::id is EcsThis * - ecs_term_t::src::flags is EcsIsVariable * * If ecs_term_t::src is not populated, it will be automatically initialized to * the $this source for the created query. * * @param term The term. * @return True if term matches $this, false if not. */ FLECS_API bool ecs_term_match_this( const ecs_term_t *term); /** Is term matched on 0 source. * This operation checks whether a term is matched on a 0 source. A 0 source is * a term that isn't matched against anything, and can be used just to pass * (component) ids to a query iterator. * * A term has a 0 source when: * - ecs_term_t::src::id is 0 * - ecs_term_t::src::flags has EcsIsEntity set * * @param term The term. * @return True if term has 0 source, false if not. */ FLECS_API bool ecs_term_match_0( const ecs_term_t *term); /** Finalize term. * Ensure that all fields of a term are consistent and filled out. This * operation should be invoked before using and after assigning members to, or * parsing a term. When a term contains unresolved identifiers, this operation * will resolve and assign the identifiers. If the term contains any identifiers * that cannot be resolved, the operation will fail. * * An application generally does not need to invoke this operation as the APIs * that use terms (such as filters, queries and triggers) will finalize terms * when they are created. * * The name and expr parameters are optional, and only used for giving more * descriptive error messages. * * @param world The world. * @param term The term to finalize. * @return Zero if success, nonzero if an error occurred. */ FLECS_API int ecs_term_finalize( const ecs_world_t *world, ecs_term_t *term); /** Copy resources of a term to another term. * This operation copies one term to another term. If the source term contains * allocated resources (such as identifiers), they will be duplicated so that * no memory is shared between the terms. * * @param src The term to copy from. * @return The destination term. */ FLECS_API ecs_term_t ecs_term_copy( const ecs_term_t *src); /** Move resources of a term to another term. * Same as copy, but moves resources from src, if src->move is set to true. If * src->move is not set to true, this operation will do a copy. * * The conditional move reduces redundant allocations in scenarios where a list * of terms is partially created with allocated resources. * * @param src The term to move from. * @return The destination term. */ FLECS_API ecs_term_t ecs_term_move( ecs_term_t *src); /** Free resources of term. * This operation frees all resources (such as identifiers) of a term. The term * itself is not freed. * * @param term The term to free. */ FLECS_API void ecs_term_fini( ecs_term_t *term); /** Initialize filter * A filter is a lightweight object that can be used to query for entities in * a world. Filters, as opposed to queries, do not cache results. They are * therefore slower to iterate, but are faster to create. * * When a filter is copied by value, make sure to use "ecs_filter_move" to * ensure that the terms pointer still points to the inline array: * * ecs_filter_move(&dst_filter, &src_filter) * * Alternatively, the ecs_filter_move function can be called with both arguments * set to the same filter, to ensure the pointer is valid: * * ecs_filter_move(&f, &f) * * It is possible to create a filter without allocating any memory, by setting * the .storage member in ecs_filter_desc_t. See the documentation for the * member for more details. * * @param world The world. * @param desc Properties for the filter to create. * @return The filter if successful, NULL if not successful. */ FLECS_API ecs_filter_t * ecs_filter_init( ecs_world_t *world, const ecs_filter_desc_t *desc); /** Deinitialize filter. * Free resources associated with filter. * * @param filter The filter to deinitialize. */ FLECS_API void ecs_filter_fini( ecs_filter_t *filter); /** Finalize filter. * When manually assigning an array of terms to the filter struct (so not when * using ecs_filter_init), this operation should be used to ensure that all * terms are assigned properly and all (derived) fields have been set. * * When ecs_filter_init is used to create the filter, this function should not * be called. The purpose of this operation is to support creation of filters * without allocating memory. * * @param filter The filter to finalize. * @return Zero if filter is valid, non-zero if it contains errors. * @ */ FLECS_API int ecs_filter_finalize( const ecs_world_t *world, ecs_filter_t *filter); /** Find index for $this variable. * This operation looks up the index of the $this variable. This index can * be used in operations like ecs_iter_set_var and ecs_iter_get_var. * * The operation will return -1 if the variable was not found. This happens when * a filter only has terms that are not matched on the $this variable, like a * filter that exclusively matches singleton components. * * @param filter The rule. * @return The index of the $this variable. */ FLECS_API int32_t ecs_filter_find_this_var( const ecs_filter_t *filter); /** Convert term to string expression. * Convert term to a string expression. The resulting expression is equivalent * to the same term, with the exception of And & Or operators. * * @param world The world. * @param term The term. * @return The term converted to a string. */ FLECS_API char* ecs_term_str( const ecs_world_t *world, const ecs_term_t *term); /** Convert filter to string expression. * Convert filter terms to a string expression. The resulting expression can be * parsed to create the same filter. * * @param world The world. * @param filter The filter. * @return The filter converted to a string. */ FLECS_API char* ecs_filter_str( const ecs_world_t *world, const ecs_filter_t *filter); /** Return a filter iterator. * A filter iterator lets an application iterate over entities that match the * specified filter. * * @param world The world. * @param filter The filter. * @return An iterator that can be used with ecs_filter_next. */ FLECS_API ecs_iter_t ecs_filter_iter( const ecs_world_t *world, const ecs_filter_t *filter); /** Return a chained filter iterator. * A chained iterator applies a filter to the results of the input iterator. The * resulting iterator must be iterated with ecs_filter_next. * * @param it The input iterator * @param filter The filter to apply to the iterator. * @return The chained iterator. */ FLECS_API ecs_iter_t ecs_filter_chain_iter( const ecs_iter_t *it, const ecs_filter_t *filter); /** Get pivot term for filter. * The pivot term is the term that matches the smallest set of tables, and is * a good default starting point for a search. * * The following conditions must be met for a term to be considered as pivot: * - It must have a This subject * - It must have the And operator * * When a filter does not have any terms that match those conditions, it will * return -1. * * If one or more terms in the filter have no matching tables the filter won't * yield any results. In this case the operation will return -2 which gives a * search function the option to early out. * * @param world The world. * @param filter The filter. * @return Index of the pivot term (use with filter->terms) */ FLECS_API int32_t ecs_filter_pivot_term( const ecs_world_t *world, const ecs_filter_t *filter); /** Iterate tables matched by filter. * This operation progresses the filter iterator to the next table. The * iterator must have been initialized with `ecs_filter_iter`. This operation * must be invoked at least once before interpreting the contents of the * iterator. * * @param it The iterator * @return True if more data is available, false if not. */ FLECS_API bool ecs_filter_next( ecs_iter_t *it); /** Same as ecs_filter_next, but always instanced. * See instanced property of ecs_filter_desc_t. * * @param it The iterator * @return True if more data is available, false if not. */ FLECS_API bool ecs_filter_next_instanced( ecs_iter_t *it); /** Move resources of one filter to another. * * @param dst The destination filter. * @param src The source filter. */ FLECS_API void ecs_filter_move( ecs_filter_t *dst, ecs_filter_t *src); /** Copy resources of one filter to another. * * @param dst The destination filter. * @param src The source filter. */ FLECS_API void ecs_filter_copy( ecs_filter_t *dst, const ecs_filter_t *src); /** @} */ /** * @defgroup queries Queries * @brief Functions for working with `ecs_query_t`. * @{ */ /** Create a query. * This operation creates a query. Queries are used to iterate over entities * that match a filter and are the fastest way to find and iterate over entities * and their components. * * Queries should be created once, and reused multiple times. While iterating a * query is a cheap operation, creating and deleting a query is expensive. The * reason for this is that queries are "prematched", which means that a query * stores state about which entities (or rather, tables) match with the query. * Building up this state happens during query creation. * * Once a query is created, matching only happens when new tables are created. * In most applications this is an infrequent process, since it only occurs when * a new combination of components is introduced. While matching is expensive, * it is importent to note that matching does not happen on a per-entity basis, * but on a per-table basis. This means that the average time spent on matching * per frame should rapidly approach zero over the lifetime of an application. * * A query provides direct access to the component arrays. When an application * creates/deletes entities or adds/removes components, these arrays can shift * component values around, or may grow in size. This can cause unexpected or * undefined behavior to occur if these operations are performed while * iterating. To prevent this from happening an application should either not * perform these operations while iterating, or use deferred operations (see * ecs_defer_begin and ecs_defer_end). * * Queries can be created and deleted dynamically. If a query was not deleted * (using ecs_query_fini) before the world is deleted, it will be deleted * automatically. * * @param world The world. * @param desc A structure describing the query properties. * @return The new query. */ FLECS_API ecs_query_t* ecs_query_init( ecs_world_t *world, const ecs_query_desc_t *desc); /** Destroy a query. * This operation destroys a query and its resources. If the query is used as * the parent of subqueries, those subqueries will be orphaned and must be * deinitialized as well. * * @param query The query. */ FLECS_API void ecs_query_fini( ecs_query_t *query); /** Get filter from a query. * This operation obtains a pointer to the internally constructed filter * of the query and can be used to introspect the query terms. * * @param query The query. * @return The filter. */ FLECS_API const ecs_filter_t* ecs_query_get_filter( const ecs_query_t *query); /** Return a query iterator. * A query iterator lets an application iterate over entities that match the * specified query. If a sorting function is specified, the query will check * whether a resort is required upon creating the iterator. * * Creating a query iterator is a cheap operation that does not allocate any * resources. An application does not need to deinitialize or free a query * iterator before it goes out of scope. * * To iterate the iterator, an application should use ecs_query_next to progress * the iterator and test if it has data. * * Query iteration requires an outer and an inner loop. The outer loop uses * ecs_query_next to test if new tables are available. The inner loop iterates * the entities in the table, and is usually a for loop that uses iter.count to * loop through the entities and component arrays. * * The two loops are necessary because of how data is stored internally. * Entities are grouped by the components they have, in tables. A single query * can (and often does) match with multiple tables. Because each table has its * own set of arrays, an application has to reobtain pointers to those arrays * for each matching table. * * @param world The world or stage, when iterating in readonly mode. * @param query The query to iterate. * @return The query iterator. */ FLECS_API ecs_iter_t ecs_query_iter( const ecs_world_t *world, ecs_query_t *query); /** Progress the query iterator. * This operation progresses the query iterator to the next table. The * iterator must have been initialized with `ecs_query_iter`. This operation * must be invoked at least once before interpreting the contents of the * iterator. * * @param iter The iterator. * @returns True if more data is available, false if not. */ FLECS_API bool ecs_query_next( ecs_iter_t *iter); /** Same as ecs_query_next, but always instanced. * See "instanced" property of ecs_filter_desc_t. * * @param iter The iterator. * @returns True if more data is available, false if not. */ FLECS_API bool ecs_query_next_instanced( ecs_iter_t *iter); /** Fast alternative to ecs_query_next that only returns matched tables. * This operation only populates the ecs_iter_t::table field. To access the * matched components, call ecs_query_populate. * * If this operation is used with a query that has inout/out terms, those terms * will not be marked dirty unless ecs_query_populate is called. * * @param iter The iterator. * @returns True if more data is available, false if not. */ FLECS_API bool ecs_query_next_table( ecs_iter_t *iter); /** Populate iterator fields. * This operation can be combined with ecs_query_next_table to populate the * iterator fields for the current table. * * Populating fields conditionally can save time when a query uses change * detection, and only needs iterator data when the table has changed. When this * operation is called, inout/out terms will be marked dirty. * * In cases where inout/out terms are conditionally written and no changes * were made after calling ecs_query_populate, the ecs_query_skip function can * be called to prevent the matched table components from being marked dirty. * * This operation does should not be used with queries that match disabled * components, union relationships, or with queries that use order_by. * * When the when_changed argument is set to true, the iterator data will only * populate when the data has changed, using query change detection. * * @param iter The iterator. * @param when_changed Only populate data when result has changed. */ FLECS_API int ecs_query_populate( ecs_iter_t *iter, bool when_changed); /** Returns whether the query data changed since the last iteration. * The operation will return true after: * - new entities have been matched with * - new tables have been matched/unmatched with * - matched entities were deleted * - matched components were changed * * The operation will not return true after a write-only (EcsOut) or filter * (EcsInOutNone) term has changed, when a term is not matched with the * current table (This subject) or for tag terms. * * The changed state of a table is reset after it is iterated. If a iterator was * not iterated until completion, tables may still be marked as changed. * * If no iterator is provided the operation will return the changed state of the * all matched tables of the query. * * If an iterator is provided, the operation will return the changed state of * the currently returned iterator result. The following preconditions must be * met before using an iterator with change detection: * * - The iterator is a query iterator (created with ecs_query_iter) * - The iterator must be valid (ecs_query_next must have returned true) * - The iterator must be instanced * * @param query The query (optional if 'it' is provided). * @param it The iterator result to test (optional if 'query' is provided). * @return true if entities changed, otherwise false. */ FLECS_API bool ecs_query_changed( ecs_query_t *query, const ecs_iter_t *it); /** Skip a table while iterating. * This operation lets the query iterator know that a table was skipped while * iterating. A skipped table will not reset its changed state, and the query * will not update the dirty flags of the table for its out columns. * * Only valid iterators must be provided (next has to be called at least once & * return true) and the iterator must be a query iterator. * * @param it The iterator result to skip. */ FLECS_API void ecs_query_skip( ecs_iter_t *it); /** Set group to iterate for query iterator. * This operation limits the results returned by the query to only the selected * group id. The query must have a group_by function, and the iterator must * be a query iterator. * * Groups are sets of tables that are stored together in the query cache based * on a group id, which is calculated per table by the group_by function. To * iterate a group, an iterator only needs to know the first and last cache node * for that group, which can both be found in a fast O(1) operation. * * As a result, group iteration is one of the most efficient mechanisms to * filter out large numbers of entities, even if those entities are distributed * across many tables. This makes it a good fit for things like dividing up * a world into cells, and only iterating cells close to a player. * * The group to iterate must be set before the first call to ecs_query_next. No * operations that can add/remove components should be invoked between calling * ecs_query_set_group and ecs_query_next. * * @param it The query iterator. * @param group_id The group to iterate. */ FLECS_API void ecs_query_set_group( ecs_iter_t *it, uint64_t group_id); /** Get context of query group. * This operation returns the context of a query group as returned by the * on_group_create callback. * * @param query The query. * @param group_id The group for which to obtain the context. * @return The group context, NULL if the group doesn't exist. */ FLECS_API void* ecs_query_get_group_ctx( const ecs_query_t *query, uint64_t group_id); /** Get information about query group. * This operation returns information about a query group, including the group * context returned by the on_group_create callback. * * @param query The query. * @param group_id The group for which to obtain the group info. * @return The group info, NULL if the group doesn't exist. */ FLECS_API const ecs_query_group_info_t* ecs_query_get_group_info( const ecs_query_t *query, uint64_t group_id); /** Returns whether query is orphaned. * When the parent query of a subquery is deleted, it is left in an orphaned * state. The only valid operation on an orphaned query is deleting it. Only * subqueries can be orphaned. * * @param query The query. * @return true if query is orphaned, otherwise false. */ FLECS_API bool ecs_query_orphaned( const ecs_query_t *query); /** Convert query to string. * * @param query The query. * @return The query string. */ FLECS_API char* ecs_query_str( const ecs_query_t *query); /** Returns number of tables query matched with. * * @param query The query. * @return The number of matched tables. */ FLECS_API int32_t ecs_query_table_count( const ecs_query_t *query); /** Returns number of empty tables query matched with. * * @param query The query. * @return The number of matched empty tables. */ FLECS_API int32_t ecs_query_empty_table_count( const ecs_query_t *query); /** Returns number of entities query matched with. * This operation iterates all non-empty tables in the query cache to find the * total number of entities. * * @param query The query. * @return The number of matched entities. */ FLECS_API int32_t ecs_query_entity_count( const ecs_query_t *query); /** Get query ctx. * Return the value set in ecs_query_desc_t::ctx. * * @param query The query. * @return The context. */ FLECS_API void* ecs_query_get_ctx( const ecs_query_t *query); /** Get query binding ctx. * Return the value set in ecs_query_desc_t::binding_ctx. * * @param query The query. * @return The context. */ FLECS_API void* ecs_query_get_binding_ctx( const ecs_query_t *query); /** @} */ /** * @defgroup observer Observers * @brief Functions for working with events and observers. * @{ */ /** Send event. * This sends an event to matching triggers & is the mechanism used by flecs * itself to send OnAdd, OnRemove, etc events. * * Applications can use this function to send custom events, where a custom * event can be any regular entity. * * Applications should not send builtin flecs events, as this may violate * assumptions the code makes about the conditions under which those events are * sent. * * Triggers are invoked synchronously. It is therefore safe to use stack-based * data as event context, which can be set in the "param" member. * * @param world The world. * @param desc Event parameters. */ FLECS_API void ecs_emit( ecs_world_t *world, ecs_event_desc_t *desc); /** Create observer. * Observers are like triggers, but can subscribe for multiple terms. An * observer only triggers when the source of the event meets all terms. * * See the documentation for ecs_observer_desc_t for more details. * * @param world The world. * @param desc The observer creation parameters. */ FLECS_API ecs_entity_t ecs_observer_init( ecs_world_t *world, const ecs_observer_desc_t *desc); /** Default run action for observer. * This function can be called from a custom observer run action (see * ecs_observer_desc_t::run for more details). This function ensures that the * observer's filter is applied to the iterator's table, filters out duplicate * events and implements EcsMonitor logic. * * @param it The iterator. * @return True if the observer was invoked. */ FLECS_API bool ecs_observer_default_run_action( ecs_iter_t *it); /** Get observer ctx. * Return the value set in ecs_observer_desc_t::ctx. * * @param world The world. * @param observer The observer. * @return The context. */ FLECS_API void* ecs_observer_get_ctx( const ecs_world_t *world, ecs_entity_t observer); /** Get observer binding ctx. * Return the value set in ecs_observer_desc_t::binding_ctx. * * @param world The world. * @param observer The observer. * @return The context. */ FLECS_API void* ecs_observer_get_binding_ctx( const ecs_world_t *world, ecs_entity_t observer); /** @} */ /** * @defgroup iterator Iterators * @brief Functions for working with `ecs_iter_t`. * @{ */ /** Create iterator from poly object. * The provided poly object must have the iterable mixin. If an object is * provided that does not have the mixin, the function will assert. * * When a filter is provided, an array of two iterators must be passed to the * function. This allows the mixin implementation to create a chained iterator * when necessary, which requires two iterator objects. * * If a filter is provided, the first element in the array of two iterators is * the one that should be iterated. The mixin implementation may or may not set * the second element, depending on whether an iterator chain is required. * * Additionally, when a filter is provided the returned iterator will be for a * single term with the provided filter id. If the iterator is chained, the * previous iterator in the chain can be accessed through it->chain_it. * * @param world The world or stage for which to create the iterator. * @param poly The poly object from which to create the iterator. * @param iter The iterator (out, ecs_iter_t[2] when filter is set). * @param filter Optional term used for filtering the results. */ FLECS_API void ecs_iter_poly( const ecs_world_t *world, const ecs_poly_t *poly, ecs_iter_t *iter, ecs_term_t *filter); /** Progress any iterator. * This operation is useful in combination with iterators for which it is not * known what created them. Example use cases are functions that should accept * any kind of iterator (such as serializers) or iterators created from poly * objects. * * This operation is slightly slower than using a type-specific iterator (e.g. * ecs_filter_next, ecs_query_next) as it has to call a function pointer which * introduces a level of indirection. * * @param it The iterator. * @return True if iterator has more results, false if not. */ FLECS_API bool ecs_iter_next( ecs_iter_t *it); /** Cleanup iterator resources. * This operation cleans up any resources associated with the iterator. * * This operation should only be used when an iterator is not iterated until * completion (next has not yet returned false). When an iterator is iterated * until completion, resources are automatically freed. * * @param it The iterator. */ FLECS_API void ecs_iter_fini( ecs_iter_t *it); /** Count number of matched entities in query. * This operation returns the number of matched entities. If a query contains no * matched entities but still yields results (e.g. it has no terms with This * sources) the operation will return 0. * * To determine the number of matched entities, the operation iterates the * iterator until it yields no more results. * * @param it The iterator. * @return True if iterator has more results, false if not. */ FLECS_API int32_t ecs_iter_count( ecs_iter_t *it); /** Test if iterator is true. * This operation will return true if the iterator returns at least one result. * This is especially useful in combination with fact-checking rules (see the * rules addon). * * The operation requires a valid iterator. After the operation is invoked, the * application should no longer invoke next on the iterator and should treat it * as if the iterator is iterated until completion. * * @param it The iterator. * @return true if the iterator returns at least one result. */ FLECS_API bool ecs_iter_is_true( ecs_iter_t *it); /** Get first matching entity from iterator. * After this operation the application should treat the iterator as if it has * been iterated until completion. * * @param it The iterator. * @return The first matching entity, or 0 if no entities were matched. */ FLECS_API ecs_entity_t ecs_iter_first( ecs_iter_t *it); /** Set value for iterator variable. * This constrains the iterator to return only results for which the variable * equals the specified value. The default value for all variables is * EcsWildcard, which means the variable can assume any value. * * Example: * * // Rule that matches (Eats, *) * ecs_rule_t *r = ecs_rule_init(world, &(ecs_filter_desc_t){ * .terms = { * { .first.id = Eats, .second.name = "$food" } * } * }); * * int food_var = ecs_rule_find_var(r, "food"); * * // Set Food to Apples, so we're only matching (Eats, Apples) * ecs_iter_t it = ecs_rule_iter(world, r); * ecs_iter_set_var(&it, food_var, Apples); * * while (ecs_rule_next(&it)) { * for (int i = 0; i < it.count; i ++) { * // iterate as usual * } * } * * The variable must be initialized after creating the iterator and before the * first call to next. * * @param it The iterator. * @param var_id The variable index. * @param entity The entity variable value. */ FLECS_API void ecs_iter_set_var( ecs_iter_t *it, int32_t var_id, ecs_entity_t entity); /** Same as ecs_iter_set_var, but for a table. * This constrains the variable to all entities in a table. * * @param it The iterator. * @param var_id The variable index. * @param table The table variable value. */ FLECS_API void ecs_iter_set_var_as_table( ecs_iter_t *it, int32_t var_id, const ecs_table_t *table); /** Same as ecs_iter_set_var, but for a range of entities * This constrains the variable to a range of entities in a table. * * @param it The iterator. * @param var_id The variable index. * @param range The range variable value. */ FLECS_API void ecs_iter_set_var_as_range( ecs_iter_t *it, int32_t var_id, const ecs_table_range_t *range); /** Get value of iterator variable as entity. * A variable can be interpreted as entity if it is set to an entity, or if it * is set to a table range with count 1. * * This operation can only be invoked on valid iterators. The variable index * must be smaller than the total number of variables provided by the iterator * (as set in ecs_iter_t::variable_count). * * @param it The iterator. * @param var_id The variable index. * @return The variable value. */ FLECS_API ecs_entity_t ecs_iter_get_var( ecs_iter_t *it, int32_t var_id); /** Get value of iterator variable as table. * A variable can be interpreted as table if it is set as table range with * both offset and count set to 0, or if offset is 0 and count matches the * number of elements in the table. * * This operation can only be invoked on valid iterators. The variable index * must be smaller than the total number of variables provided by the iterator * (as set in ecs_iter_t::variable_count). * * @param it The iterator. * @param var_id The variable index. * @return The variable value. */ FLECS_API ecs_table_t* ecs_iter_get_var_as_table( ecs_iter_t *it, int32_t var_id); /** Get value of iterator variable as table range. * A value can be interpreted as table range if it is set as table range, or if * it is set to an entity with a non-empty type (the entity must have at least * one component, tag or relationship in its type). * * This operation can only be invoked on valid iterators. The variable index * must be smaller than the total number of variables provided by the iterator * (as set in ecs_iter_t::variable_count). * * @param it The iterator. * @param var_id The variable index. * @return The variable value. */ FLECS_API ecs_table_range_t ecs_iter_get_var_as_range( ecs_iter_t *it, int32_t var_id); /** Returns whether variable is constrained. * This operation returns true for variables set by one of the ecs_iter_set_var* * operations. * * A constrained variable is guaranteed not to change values while results are * being iterated. * * @param it The iterator. * @param var_id The variable index. * @return Whether the variable is constrained to a specified value. */ FLECS_API bool ecs_iter_var_is_constrained( ecs_iter_t *it, int32_t var_id); /** Convert iterator to string. * Prints the contents of an iterator to a string. Useful for debugging and/or * testing the output of an iterator. * * The function only converts the currently iterated data to a string. To * convert all data, the application has to manually call the next function and * call ecs_iter_str on each result. * * @param it The iterator. * @return A string representing the contents of the iterator. */ FLECS_API char* ecs_iter_str( const ecs_iter_t *it); /** Create a paged iterator. * Paged iterators limit the results to those starting from 'offset', and will * return at most 'limit' results. * * The iterator must be iterated with ecs_page_next. * * A paged iterator acts as a passthrough for data exposed by the parent * iterator, so that any data provided by the parent will also be provided by * the paged iterator. * * @param it The source iterator. * @param offset The number of entities to skip. * @param limit The maximum number of entities to iterate. * @return A page iterator. */ FLECS_API ecs_iter_t ecs_page_iter( const ecs_iter_t *it, int32_t offset, int32_t limit); /** Progress a paged iterator. * Progresses an iterator created by ecs_page_iter. * * @param it The iterator. * @return true if iterator has more results, false if not. */ FLECS_API bool ecs_page_next( ecs_iter_t *it); /** Create a worker iterator. * Worker iterators can be used to equally divide the number of matched entities * across N resources (usually threads). Each resource will process the total * number of matched entities divided by 'count'. * * Entities are distributed across resources such that the distribution is * stable between queries. Two queries that match the same table are guaranteed * to match the same entities in that table. * * The iterator must be iterated with ecs_worker_next. * * A worker iterator acts as a passthrough for data exposed by the parent * iterator, so that any data provided by the parent will also be provided by * the worker iterator. * * @param it The source iterator. * @param index The index of the current resource. * @param count The total number of resources to divide entities between. * @return A worker iterator. */ FLECS_API ecs_iter_t ecs_worker_iter( const ecs_iter_t *it, int32_t index, int32_t count); /** Progress a worker iterator. * Progresses an iterator created by ecs_worker_iter. * * @param it The iterator. * @return true if iterator has more results, false if not. */ FLECS_API bool ecs_worker_next( ecs_iter_t *it); /** Obtain data for a query field. * This operation retrieves a pointer to an array of data that belongs to the * term in the query. The index refers to the location of the term in the query, * and starts counting from one. * * For example, the query "Position, Velocity" will return the Position array * for index 1, and the Velocity array for index 2. * * When the specified field is not owned by the entity this function returns a * pointer instead of an array. This happens when the source of a field is not * the entity being iterated, such as a shared component (from a prefab), a * component from a parent, or another entity. The ecs_field_is_self operation * can be used to test dynamically if a field is owned. * * The provided size must be either 0 or must match the size of the datatype * of the returned array. If the size does not match, the operation may assert. * The size can be dynamically obtained with ecs_field_size. * * @param it The iterator. * @param size The type size of the requested data. * @param index The index of the field in the iterator. * @return A pointer to the data of the field. */ FLECS_API void* ecs_field_w_size( const ecs_iter_t *it, size_t size, int32_t index); /** Test whether the field is readonly. * This operation returns whether the field is readonly. Readonly fields are * annotated with [in], or are added as a const type in the C++ API. * * @param it The iterator. * @param index The index of the field in the iterator. * @return Whether the field is readonly. */ FLECS_API bool ecs_field_is_readonly( const ecs_iter_t *it, int32_t index); /** Test whether the field is writeonly. * This operation returns whether this is a writeonly field. Writeonly terms are * annotated with [out]. * * Serializers are not required to serialize the values of a writeonly field. * * @param it The iterator. * @param index The index of the field in the iterator. * @return Whether the field is writeonly. */ FLECS_API bool ecs_field_is_writeonly( const ecs_iter_t *it, int32_t index); /** Test whether field is set. * * @param it The iterator. * @param index The index of the field in the iterator. * @return Whether the field is set. */ FLECS_API bool ecs_field_is_set( const ecs_iter_t *it, int32_t index); /** Return id matched for field. * * @param it The iterator. * @param index The index of the field in the iterator. * @return The id matched for the field. */ FLECS_API ecs_id_t ecs_field_id( const ecs_iter_t *it, int32_t index); /** Return index of matched table column. * This function only returns column indices for fields that have been matched * on the $this variable. Fields matched on other tables will return -1. * * @param it The iterator. * @param index The index of the field in the iterator. * @return The index of the matched column, -1 if not matched. */ FLECS_API int32_t ecs_field_column_index( const ecs_iter_t *it, int32_t index); /** Return field source. * The field source is the entity on which the field was matched. * * @param it The iterator. * @param index The index of the field in the iterator. * @return The source for the field. */ FLECS_API ecs_entity_t ecs_field_src( const ecs_iter_t *it, int32_t index); /** Return field type size. * Return type size of the field. Returns 0 if the field has no data. * * @param it The iterator. * @param index The index of the field in the iterator. * @return The type size for the field. */ FLECS_API size_t ecs_field_size( const ecs_iter_t *it, int32_t index); /** Test whether the field is matched on self. * This operation returns whether the field is matched on the currently iterated * entity. This function will return false when the field is owned by another * entity, such as a parent or a prefab. * * When this operation returns false, the field must be accessed as a single * value instead of an array. Fields for which this operation returns true * return arrays with it->count values. * * @param it The iterator. * @param index The index of the field in the iterator. * @return Whether the field is matched on self. */ FLECS_API bool ecs_field_is_self( const ecs_iter_t *it, int32_t index); /** @} */ /** * @defgroup tables Tables * @brief Functions for working with `ecs_table_t`. * @{ */ /** Get type for table. * The table type is a vector that contains all component, tag and pair ids. * * @param table The table. * @return The type of the table. */ FLECS_API const ecs_type_t* ecs_table_get_type( const ecs_table_t *table); /** Get type index for id. * This operation returns the index for an id in the table's type. * * @param world The world. * @param table The table. * @param id The id. * @return The index of the id in the table type, or -1 if not found. */ FLECS_API int32_t ecs_table_get_type_index( const ecs_world_t *world, const ecs_table_t *table, ecs_id_t id); /** Get column index for id. * This operation returns the column index for an id in the table's type. If the * id is not a component, the function will return -1. * * @param world The world. * @param table The table. * @param id The component id. * @return The column index of the id, or -1 if not found/not a component. */ FLECS_API int32_t ecs_table_get_column_index( const ecs_world_t *world, const ecs_table_t *table, ecs_id_t id); /** Return number of columns in table. * Similar to ecs_table_get_type(table)->count, except that the column count * only counts the number of components in a table. * * @param table The table. * @return The number of columns in the table. */ FLECS_API int32_t ecs_table_column_count( const ecs_table_t *table); /** Convert type index to column index. * Tables have an array of columns for each component in the table. This array * does not include elements for tags, which means that the index for a * component in the table type is not necessarily the same as the index in the * column array. This operation converts from an index in the table type to an * index in the column array. * * @param table The table. * @param index The index in the table type. * @return The index in the table column array. */ FLECS_API int32_t ecs_table_type_to_column_index( const ecs_table_t *table, int32_t index); /** Convert column index to type index. * Same as ecs_table_type_to_column_index, but converts from an index in the * column array to an index in the table type. * * @param table The table. * @param index The column index. * @return The index in the table type. */ FLECS_API int32_t ecs_table_column_to_type_index( const ecs_table_t *table, int32_t index); /** Get column from table by column index. * This operation returns the component array for the provided index. * * @param table The table. * @param index The column index. * @param offset The index of the first row to return (0 for entire column). * @return The component array, or NULL if the index is not a component. */ FLECS_API void* ecs_table_get_column( const ecs_table_t *table, int32_t index, int32_t offset); /** Get column from table by component id. * This operation returns the component array for the provided component id. * * @param table The table. * @param id The component id for the column. * @param offset The index of the first row to return (0 for entire column). * @return The component array, or NULL if the index is not a component. */ FLECS_API void* ecs_table_get_id( const ecs_world_t *world, const ecs_table_t *table, ecs_id_t id, int32_t offset); /** Get column size from table. * This operation returns the component size for the provided index. * * @param table The table. * @param index The column index. * @return The component size, or 0 if the index is not a component. */ FLECS_API size_t ecs_table_get_column_size( const ecs_table_t *table, int32_t index); /** Returns the number of records in the table. * This operation returns the number of records that have been populated through * the regular (entity) API as well as the number of records that have been * inserted using the direct access API. * * @param table The table. * @return The number of records in a table. */ FLECS_API int32_t ecs_table_count( const ecs_table_t *table); /** Test if table has id. * Same as ecs_table_get_type_index(world, table, id) != -1. * * @param world The world. * @param table The table. * @param id The id. * @return True if the table has the id, false if the table doesn't. */ FLECS_API bool ecs_table_has_id( const ecs_world_t *world, const ecs_table_t *table, ecs_id_t id); /** Return depth for table in tree for relationship rel. * Depth is determined by counting the number of targets encountered while * traversing up the relationship tree for rel. Only acyclic relationships are * supported. * * @param world The world. * @param table The table. * @param rel The relationship. * @return The depth of the table in the tree. */ FLECS_API int32_t ecs_table_get_depth( const ecs_world_t *world, const ecs_table_t *table, ecs_entity_t rel); /** Get table that has all components of current table plus the specified id. * If the provided table already has the provided id, the operation will return * the provided table. * * @param world The world. * @param table The table. * @param id The id to add. * @result The resulting table. */ FLECS_API ecs_table_t* ecs_table_add_id( ecs_world_t *world, ecs_table_t *table, ecs_id_t id); /** Find table from id array. * This operation finds or creates a table with the specified array of * (component) ids. The ids in the array must be sorted, and it may not contain * duplicate elements. * * @param world The world. * @param ids The id array. * @param id_count The number of elements in the id array. * @return The table with the specified (component) ids. */ FLECS_API ecs_table_t* ecs_table_find( ecs_world_t *world, const ecs_id_t *ids, int32_t id_count); /** Get table that has all components of current table minus the specified id. * If the provided table doesn't have the provided id, the operation will return * the provided table. * * @param world The world. * @param table The table. * @param id The id to remove. * @result The resulting table. */ FLECS_API ecs_table_t* ecs_table_remove_id( ecs_world_t *world, ecs_table_t *table, ecs_id_t id); /** Lock or unlock table. * When a table is locked, modifications to it will throw an assert. When the * table is locked recursively, it will take an equal amount of unlock * operations to actually unlock the table. * * Table locks can be used to build safe iterators where it is guaranteed that * the contents of a table are not modified while it is being iterated. * * The operation only works when called on the world, and has no side effects * when called on a stage. The assumption is that when called on a stage, * operations are deferred already. * * @param world The world. * @param table The table to lock. */ FLECS_API void ecs_table_lock( ecs_world_t *world, ecs_table_t *table); /** Unlock a table. * Must be called after calling ecs_table_lock. * * @param world The world. * @param table The table to unlock. */ FLECS_API void ecs_table_unlock( ecs_world_t *world, ecs_table_t *table); /** Test table for flags. * Test if table has all of the provided flags. See * include/flecs/private/api_flags.h for a list of table flags that can be used * with this function. * * @param table The table. * @param flags The flags to test for. * @return Whether the specified flags are set for the table. */ FLECS_API bool ecs_table_has_flags( ecs_table_t *table, ecs_flags32_t flags); /** Swaps two elements inside the table. This is useful for implementing custom * table sorting algorithms. * @param world The world * @param table The table to swap elements in * @param row_1 Table element to swap with row_2 * @param row_2 Table element to swap with row_1 */ FLECS_API void ecs_table_swap_rows( ecs_world_t* world, ecs_table_t* table, int32_t row_1, int32_t row_2); /** Commit (move) entity to a table. * This operation moves an entity from its current table to the specified * table. This may cause the following actions: * - Ctor for each component in the target table * - Move for each overlapping component * - Dtor for each component in the source table. * - OnAdd triggers for non-overlapping components in the target table * - OnRemove triggers for non-overlapping components in the source table. * * This operation is a faster than adding/removing components individually. * * The application must explicitly provide the difference in components between * tables as the added/removed parameters. This can usually be derived directly * from the result of ecs_table_add_id and esc_table_remove_id. These arrays are * required to properly execute OnAdd/OnRemove triggers. * * @param world The world. * @param entity The entity to commit. * @param record The entity's record (optional, providing it saves a lookup). * @param table The table to commit the entity to. * @return True if the entity got moved, false otherwise. */ FLECS_API bool ecs_commit( ecs_world_t *world, ecs_entity_t entity, ecs_record_t *record, ecs_table_t *table, const ecs_type_t *added, const ecs_type_t *removed); /** Find record for entity. */ FLECS_API ecs_record_t* ecs_record_find( const ecs_world_t *world, ecs_entity_t entity); /** Get component pointer from column/record. */ FLECS_API void* ecs_record_get_column( const ecs_record_t *r, int32_t column, size_t c_size); /** Search for component id in table type. * This operation returns the index of first occurrance of the id in the table * type. The id may be a wildcard. * * When id_out is provided, the function will assign it with the found id. The * found id may be different from the provided id if it is a wildcard. * * This is a constant time operation. * * @param world The world. * @param table The table. * @param id The id to search for. * @param id_out If provided, it will be set to the found id (optional). * @return The index of the id in the table type. */ FLECS_API int32_t ecs_search( const ecs_world_t *world, const ecs_table_t *table, ecs_id_t id, ecs_id_t *id_out); /** Search for component id in table type starting from an offset. * This operation is the same as ecs_search, but starts searching from an offset * in the table type. * * This operation is typically called in a loop where the resulting index is * used in the next iteration as offset: * * int32_t index = -1; * while ((index = ecs_search_offset(world, table, offset, id, NULL))) { * // do stuff * } * * Depending on how the operation is used it is either linear or constant time. * When the id has the form (id) or (rel, *) and the operation is invoked as * in the above example, it is guaranteed to be constant time. * * If the provided id has the form (*, tgt) the operation takes linear time. The * reason for this is that ids for an target are not packed together, as they * are sorted relationship first. * * If the id at the offset does not match the provided id, the operation will do * a linear search to find a matching id. * * @param world The world. * @param table The table. * @param offset Offset from where to start searching. * @param id The id to search for. * @param id_out If provided, it will be set to the found id (optional). * @return The index of the id in the table type. */ FLECS_API int32_t ecs_search_offset( const ecs_world_t *world, const ecs_table_t *table, int32_t offset, ecs_id_t id, ecs_id_t *id_out); /** Search for component/relationship id in table type starting from an offset. * This operation is the same as ecs_search_offset, but has the additional * capability of traversing relationships to find a component. For example, if * an application wants to find a component for either the provided table or a * prefab (using the IsA relationship) of that table, it could use the operation * like this: * * int32_t index = ecs_search_relation( * world, // the world * table, // the table * 0, // offset 0 * ecs_id(Position), // the component id * EcsIsA, // the relationship to traverse * 0, // start at depth 0 (the table itself) * 0, // no depth limit * NULL, // (optional) entity on which component was found * NULL, // see above * NULL); // internal type with information about matched id * * The operation searches depth first. If a table type has 2 IsA relationships, the * operation will first search the IsA tree of the first relationship. * * When choosing betwen ecs_search, ecs_search_offset and ecs_search_relation, * the simpler the function the better its performance. * * @param world The world. * @param table The table. * @param offset Offset from where to start searching. * @param id The id to search for. * @param rel The relationship to traverse (optional). * @param flags Whether to search EcsSelf and/or EcsUp. * @param subject_out If provided, it will be set to the matched entity. * @param id_out If provided, it will be set to the found id (optional). * @param tr_out Internal datatype. * @return The index of the id in the table type. */ FLECS_API int32_t ecs_search_relation( const ecs_world_t *world, const ecs_table_t *table, int32_t offset, ecs_id_t id, ecs_entity_t rel, ecs_flags32_t flags, /* EcsSelf and/or EcsUp */ ecs_entity_t *subject_out, ecs_id_t *id_out, struct ecs_table_record_t **tr_out); /** @} */ /** * @defgroup values Values * @brief Construct, destruct, copy and move dynamically created values. * @{ */ /** Construct a value in existing storage * * @param world The world. * @param type The type of the value to create. * @param ptr Pointer to a value of type 'type' * @return Zero if success, nonzero if failed. */ FLECS_API int ecs_value_init( const ecs_world_t *world, ecs_entity_t type, void *ptr); /** Construct a value in existing storage * * @param world The world. * @param ti The type info of the type to create. * @param ptr Pointer to a value of type 'type' * @return Zero if success, nonzero if failed. */ FLECS_API int ecs_value_init_w_type_info( const ecs_world_t *world, const ecs_type_info_t *ti, void *ptr); /** Construct a value in new storage * * @param world The world. * @param type The type of the value to create. * @return Pointer to type if success, NULL if failed. */ FLECS_API void* ecs_value_new( ecs_world_t *world, ecs_entity_t type); /** Construct a value in new storage * * @param world The world. * @param ti The type info of the type to create. * @return Pointer to type if success, NULL if failed. */ void* ecs_value_new_w_type_info( ecs_world_t *world, const ecs_type_info_t *ti); /** Destruct a value * * @param world The world. * @param ti Type info of the value to destruct. * @param ptr Pointer to constructed value of type 'type'. * @return Zero if success, nonzero if failed. */ int ecs_value_fini_w_type_info( const ecs_world_t *world, const ecs_type_info_t *ti, void *ptr); /** Destruct a value * * @param world The world. * @param type The type of the value to destruct. * @param ptr Pointer to constructed value of type 'type'. * @return Zero if success, nonzero if failed. */ FLECS_API int ecs_value_fini( const ecs_world_t *world, ecs_entity_t type, void* ptr); /** Destruct a value, free storage * * @param world The world. * @param type The type of the value to destruct. * @return Zero if success, nonzero if failed. */ FLECS_API int ecs_value_free( ecs_world_t *world, ecs_entity_t type, void* ptr); /** Copy value. * * @param world The world. * @param ti Type info of the value to copy. * @param dst Pointer to the storage to copy to. * @param src Pointer to the value to copy. * @return Zero if success, nonzero if failed. */ FLECS_API int ecs_value_copy_w_type_info( const ecs_world_t *world, const ecs_type_info_t *ti, void* dst, const void *src); /** Copy value. * * @param world The world. * @param type The type of the value to copy. * @param dst Pointer to the storage to copy to. * @param src Pointer to the value to copy. * @return Zero if success, nonzero if failed. */ FLECS_API int ecs_value_copy( const ecs_world_t *world, ecs_entity_t type, void* dst, const void *src); /** Move value. * * @param world The world. * @param ti Type info of the value to move. * @param dst Pointer to the storage to move to. * @param src Pointer to the value to move. * @return Zero if success, nonzero if failed. */ int ecs_value_move_w_type_info( const ecs_world_t *world, const ecs_type_info_t *ti, void* dst, void *src); /** Move value. * * @param world The world. * @param type The type of the value to move. * @param dst Pointer to the storage to move to. * @param src Pointer to the value to move. * @return Zero if success, nonzero if failed. */ int ecs_value_move( const ecs_world_t *world, ecs_entity_t type, void* dst, void *src); /** Move construct value. * * @param world The world. * @param ti Type info of the value to move. * @param dst Pointer to the storage to move to. * @param src Pointer to the value to move. * @return Zero if success, nonzero if failed. */ int ecs_value_move_ctor_w_type_info( const ecs_world_t *world, const ecs_type_info_t *ti, void* dst, void *src); /** Move construct value. * * @param world The world. * @param type The type of the value to move. * @param dst Pointer to the storage to move to. * @param src Pointer to the value to move. * @return Zero if success, nonzero if failed. */ int ecs_value_move_ctor( const ecs_world_t *world, ecs_entity_t type, void* dst, void *src); /** @} */ /** @} */ /** * @defgroup c_addons Addons * @brief C APIs for addons. * * \ingroup c * * @{ * @} */ #include "flecs/addons/flecs_c.h" #ifdef __cplusplus } #endif #include "flecs/private/addons.h" #endif