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Properly link flecs library

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This commit is contained in:
Klemen Plestenjak
2023-11-09 11:38:29 +01:00
parent dc585396c3
commit 8edcf9305c
1392 changed files with 390081 additions and 164 deletions
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16
engine/libs/flecs/examples/cpp/rules/basics/include/basics.h Normal file
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#ifndef BASICS_H
#define BASICS_H
/* This generated file contains includes for project dependencies */
#include "basics/bake_config.h"
#ifdef __cplusplus
extern "C" {
#endif
#ifdef __cplusplus
}
#endif
#endif

24
engine/libs/flecs/examples/cpp/rules/basics/include/basics/bake_config.h Normal file
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/*
)
(.)
.|.
| |
_.--| |--._
.-'; ;`-'& ; `&.
\ & ; & &_/
|"""---...---"""|
\ | | | | | | | /
`---.|.|.|.---'
* This file is generated by bake.lang.c for your convenience. Headers of
* dependencies will automatically show up in this file. Include bake_config.h
* in your main project file. Do not edit! */
#ifndef BASICS_BAKE_CONFIG_H
#define BASICS_BAKE_CONFIG_H
/* Headers of public dependencies */
#include <flecs.h>
#endif

11
engine/libs/flecs/examples/cpp/rules/basics/project.json Normal file
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{
"id": "basics",
"type": "application",
"value": {
"use": [
"flecs"
],
"language": "c++",
"public": false
}
}

65
engine/libs/flecs/examples/cpp/rules/basics/src/main.cpp Normal file
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#include <basics.h>
#include <iostream>
struct Eats { };
struct Healthy { };
int main(int, char *[]) {
flecs::world ecs;
flecs::entity Apples = ecs.entity("Apples").add<Healthy>();
flecs::entity Salad = ecs.entity("Salad").add<Healthy>();
flecs::entity Burgers = ecs.entity("Burgers");
flecs::entity Pizza = ecs.entity("Pizza");
flecs::entity Chocolate = ecs.entity("Chocolate");
ecs.entity("Bob")
.add<Eats>(Apples)
.add<Eats>(Burgers)
.add<Eats>(Pizza);
ecs.entity("Alice")
.add<Eats>(Salad)
.add<Eats>(Chocolate)
.add<Eats>(Apples);
// Here we're creating a rule that in the query DSL would look like this:
// Eats($This, $Food), Healthy($Food)
//
// Rules are similar to queries, but support more advanced features. This
// example shows how the basics of how to use rules & variables.
flecs::rule<> r = ecs.rule_builder()
// Identifiers that start with _ are query variables. Query variables
// are like wildcards, but enforce that the entity substituted by the
// wildcard is the same across terms.
//
// For example, in this query it is not guaranteed that the entity
// substituted by the * for Eats is the same as for Healthy:
// (Eats, *), Healthy(*)
//
// By replacing * with _Food, both terms are constrained to use the
// same entity.
.with<Eats>("$Food")
.with<Healthy>().src("$Food")
.build();
// Lookup the index of the variable. This will let us quickly lookup its
// value while we're iterating.
int food_var = r.find_var("Food");
// Iterate the rule
r.each([&](flecs::iter& it, size_t index) {
std::cout
<< it.entity(index).name()
<< " eats " << it.get_var(food_var).name()
<< "\n";
});
// Rules need to be explicitly deleted.
r.destruct();
// Output:
// Bob eats Apples
// Alice eats Apples
// Alice eats Salad
}

16
engine/libs/flecs/examples/cpp/rules/component_inheritance/include/component_inheritance.h Normal file
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#ifndef COMPONENT_INHERITANCE_H
#define COMPONENT_INHERITANCE_H
/* This generated file contains includes for project dependencies */
#include "component_inheritance/bake_config.h"
#ifdef __cplusplus
extern "C" {
#endif
#ifdef __cplusplus
}
#endif
#endif

24
engine/libs/flecs/examples/cpp/rules/component_inheritance/include/component_inheritance/bake_config.h Normal file
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/*
)
(.)
.|.
| |
_.--| |--._
.-'; ;`-'& ; `&.
\ & ; & &_/
|"""---...---"""|
\ | | | | | | | /
`---.|.|.|.---'
* This file is generated by bake.lang.c for your convenience. Headers of
* dependencies will automatically show up in this file. Include bake_config.h
* in your main project file. Do not edit! */
#ifndef COMPONENT_INHERITANCE_BAKE_CONFIG_H
#define COMPONENT_INHERITANCE_BAKE_CONFIG_H
/* Headers of public dependencies */
#include <flecs.h>
#endif

11
engine/libs/flecs/examples/cpp/rules/component_inheritance/project.json Normal file
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{
"id": "component_inheritance",
"type": "application",
"value": {
"use": [
"flecs"
],
"language": "c++",
"public": false
}
}

58
engine/libs/flecs/examples/cpp/rules/component_inheritance/src/main.cpp Normal file
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#include <component_inheritance.h>
#include <iostream>
// This example shows how rules can be used to match simple inheritance trees.
struct Unit { };
struct CombatUnit : Unit { };
struct MeleeUnit : CombatUnit { };
struct RangedUnit : CombatUnit { };
struct Warrior : MeleeUnit { };
struct Wizard : RangedUnit { };
struct Marksman : RangedUnit { };
struct Builder : Unit { };
int main(int, char *[]) {
flecs::world ecs;
// Make the ECS aware of the inheritance relationships. Note that IsA
// relationship used here is the same as in the prefab example.
ecs.component<CombatUnit>().is_a<Unit>();
ecs.component<MeleeUnit>().is_a<CombatUnit>();
ecs.component<RangedUnit>().is_a<CombatUnit>();
ecs.component<Warrior>().is_a<MeleeUnit>();
ecs.component<Wizard>().is_a<RangedUnit>();
ecs.component<Marksman>().is_a<RangedUnit>();
ecs.component<Builder>().is_a<Unit>();
// Create a few units
ecs.entity("warrior_1").add<Warrior>();
ecs.entity("warrior_2").add<Warrior>();
ecs.entity("marksman_1").add<Marksman>();
ecs.entity("marksman_2").add<Marksman>();
ecs.entity("wizard_1").add<Wizard>();
ecs.entity("wizard_2").add<Wizard>();
ecs.entity("builder_1").add<Builder>();
ecs.entity("builder_2").add<Builder>();
// Create a rule to find all ranged units
flecs::rule<RangedUnit> r = ecs.rule<RangedUnit>();
// Iterate the rule
r.each([](flecs::entity e, RangedUnit) {
std::cout << "Unit " << e.name() << " found\n";
});
r.destruct();
// Output:
// Unit wizard_1 found
// Unit wizard_2 found
// Unit marksman_1 found
// Unit marksman_2 found
}

16
engine/libs/flecs/examples/cpp/rules/cyclic_variables/include/cyclic_variables.h Normal file
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#ifndef CYCLIC_VARIABLES_H
#define CYCLIC_VARIABLES_H
/* This generated file contains includes for project dependencies */
#include "cyclic_variables/bake_config.h"
#ifdef __cplusplus
extern "C" {
#endif
#ifdef __cplusplus
}
#endif
#endif

24
engine/libs/flecs/examples/cpp/rules/cyclic_variables/include/cyclic_variables/bake_config.h Normal file
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/*
)
(.)
.|.
| |
_.--| |--._
.-'; ;`-'& ; `&.
\ & ; & &_/
|"""---...---"""|
\ | | | | | | | /
`---.|.|.|.---'
* This file is generated by bake.lang.c for your convenience. Headers of
* dependencies will automatically show up in this file. Include bake_config.h
* in your main project file. Do not edit! */
#ifndef CYCLIC_VARIABLES_BAKE_CONFIG_H
#define CYCLIC_VARIABLES_BAKE_CONFIG_H
/* Headers of public dependencies */
#include <flecs.h>
#endif

11
engine/libs/flecs/examples/cpp/rules/cyclic_variables/project.json Normal file
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{
"id": "cyclic_variables",
"type": "application",
"value": {
"use": [
"flecs"
],
"language": "c++",
"public": true
}
}

67
engine/libs/flecs/examples/cpp/rules/cyclic_variables/src/main.cpp Normal file
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#include <cyclic_variables.h>
#include <iostream>
// This example shows how a rule may have terms with cyclic dependencies on
// variables.
struct Likes { };
int main(int, char *[]) {
flecs::world ecs;
flecs::entity bob = ecs.entity("Bob");
flecs::entity alice = ecs.entity("Alice");
flecs::entity john = ecs.entity("John");
flecs::entity jane = ecs.entity("Jane");
bob.add<Likes>(alice);
alice.add<Likes>(bob);
john.add<Likes>(jane);
jane.add<Likes>(john);
bob.add<Likes>(jane); // inserting a bit of drama
// The following rule will only return entities that have a cyclic Likes
// relationship- that is they must both like each other.
//
// The equivalent query in the DSL is:
// Likes($X, $Y), Likes($Y, $X)
//
// This is also an example of a query where all sources are variables. By
// default queries use the builtin "This" variable as subject, which is what
// populates the entities array in the query result (accessed by the
// iter::entity function).
//
// Because this query does not use This at all, the entities array will not
// be populated, and it.count() will always be 0.
flecs::rule<> r = ecs.rule_builder()
.with<Likes>("$Y").src("$X")
.with<Likes>("$X").src("$Y")
.build();
// Lookup the index of the variables. This will let us quickly lookup their
// values while we're iterating.
int x_var = r.find_var("X");
int y_var = r.find_var("Y");
// Because the query doesn't use the This variable we cannot use "each"
// which iterates the entities array. Instead we can use iter like this:
r.iter([&](flecs::iter& it) {
flecs::entity x = it.get_var(x_var);
flecs::entity y = it.get_var(y_var);
std::cout << x.name() << " likes " << y.name() << "\n";
});
// Output
// Alice likes Bob
// Bob likes Alice
// Jane likes John
// John likes Jane
// Note that the rule returns each pair twice. The reason for this is that
// the goal of the rule engine is to return all "facts" that are true
// within the given constraints. Since we did not give it any constraints
// that would favor a person being matched by X or Y, the rule engine
// returns both.
r.destruct();
}

5
engine/libs/flecs/examples/cpp/rules/facts/.gitignore vendored Normal file
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.bake_cache
.DS_Store
.vscode
gcov
bin

16
engine/libs/flecs/examples/cpp/rules/facts/include/facts.h Normal file
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#ifndef FACTS_H
#define FACTS_H
/* This generated file contains includes for project dependencies */
#include "facts/bake_config.h"
#ifdef __cplusplus
extern "C" {
#endif
#ifdef __cplusplus
}
#endif
#endif

24
engine/libs/flecs/examples/cpp/rules/facts/include/facts/bake_config.h Normal file
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/*
)
(.)
.|.
| |
_.--| |--._
.-'; ;`-'& ; `&.
\ & ; & &_/
|"""---...---"""|
\ | | | | | | | /
`---.|.|.|.---'
* This file is generated by bake.lang.c for your convenience. Headers of
* dependencies will automatically show up in this file. Include bake_config.h
* in your main project file. Do not edit! */
#ifndef FACTS_BAKE_CONFIG_H
#define FACTS_BAKE_CONFIG_H
/* Headers of public dependencies */
#include <flecs.h>
#endif

10
engine/libs/flecs/examples/cpp/rules/facts/project.json Normal file
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{
"id": "facts",
"type": "application",
"value": {
"use": [
"flecs"
],
"language": "c++"
}
}

90
engine/libs/flecs/examples/cpp/rules/facts/src/main.cpp Normal file
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#include <facts.h>
#include <iostream>
// This example shows how to use rules for testing facts. A fact is a query that
// has no variable elements. Consider a regular ECS query like this:
// Position, Velocity
//
// When written out in full, this query looks like:
// Position($This), Velocity($This)
//
// "This" is a (builtin) query variable that is unknown before we evaluate the
// query. Therefore this query does not test a fact, we can't know which values
// This will assume.
//
// An example of a fact-checking query is:
// IsA(Cat, Animal)
//
// This is a fact: the query has no elements that are unknown before evaluating
// the query. A rule that checks a fact does not return entities, but will
// instead return the reasons why a fact is true (if it is true).
struct Likes { };
int main(int, char *[]) {
flecs::world ecs;
flecs::entity bob = ecs.entity("Bob");
flecs::entity alice = ecs.entity("Alice");
flecs::entity jane = ecs.entity("Jane");
flecs::entity john = ecs.entity("John");
bob.add<Likes>(alice);
alice.add<Likes>(bob);
jane.add<Likes>(john);
john.add<Likes>(jane);
bob.add<Likes>(john); // bit of drama
// Create a rule that checks if two entities like each other. By itself this
// rule is not a fact, but we can use it to check facts by populating both
// of its variables.
//
// The equivalent query in the DSL is:
// Likes($X, $Y), Likes($Y, $X)
//
// Instead of using variables we could have created a rule that referred the
// entities directly, but then we would have to create a rule for each
// fact, vs reusing a single rule for multiple facts.
flecs::rule<> friends = ecs.rule_builder()
.with<Likes>("$Y").src("$X")
.with<Likes>("$X").src("$Y")
.build();
int x_var = friends.find_var("X");
int y_var = friends.find_var("Y");
// Check a few facts
std::cout << "Are Bob and Alice friends? " <<
(friends.iter()
.set_var(x_var, bob)
.set_var(y_var, alice)
.is_true() ? "Yes\n" : "No\n");
std::cout << "Are Bob and John friends? " <<
(friends.iter()
.set_var(x_var, bob)
.set_var(y_var, john)
.is_true() ? "Yes\n" : "No\n");
std::cout << "Are Jane and John friends? " <<
(friends.iter()
.set_var(x_var, jane)
.set_var(y_var, john)
.is_true() ? "Yes\n" : "No\n");
// It doesn't matter who we assign to X or Y. After the variables are
// substituted, either yields a fact that is true.
std::cout << "Are John and Jane friends? " <<
(friends.iter()
.set_var(x_var, john)
.set_var(y_var, jane)
.is_true() ? "Yes\n" : "No\n");
// Output
// Are Bob and Alice friends? Yes
// Are Bob and John friends? No
// Are Jane and John friends? Yes
// Are John and Jane friends? Yes
}

16
engine/libs/flecs/examples/cpp/rules/setting_variables/include/setting_variables.h Normal file
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#ifndef SETTING_VARIABLES_H
#define SETTING_VARIABLES_H
/* This generated file contains includes for project dependencies */
#include "setting_variables/bake_config.h"
#ifdef __cplusplus
extern "C" {
#endif
#ifdef __cplusplus
}
#endif
#endif

24
engine/libs/flecs/examples/cpp/rules/setting_variables/include/setting_variables/bake_config.h Normal file
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/*
)
(.)
.|.
| |
_.--| |--._
.-'; ;`-'& ; `&.
\ & ; & &_/
|"""---...---"""|
\ | | | | | | | /
`---.|.|.|.---'
* This file is generated by bake.lang.c for your convenience. Headers of
* dependencies will automatically show up in this file. Include bake_config.h
* in your main project file. Do not edit! */
#ifndef SETTING_VARIABLES_BAKE_CONFIG_H
#define SETTING_VARIABLES_BAKE_CONFIG_H
/* Headers of public dependencies */
#include <flecs.h>
#endif

11
engine/libs/flecs/examples/cpp/rules/setting_variables/project.json Normal file
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{
"id": "setting_variables",
"type": "application",
"value": {
"use": [
"flecs"
],
"language": "c++",
"public": false
}
}

108
engine/libs/flecs/examples/cpp/rules/setting_variables/src/main.cpp Normal file
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#include <setting_variables.h>
#include <iostream>
// This example extends the component_inheritance example, and shows how
// we can use a single rule to match units from different players and platoons
// by setting query variables before we iterate.
//
// The units in this example belong to a platoon, with the platoons belonging
// to a player.
// Unit datamodel
struct Unit { };
struct CombatUnit : Unit { };
struct MeleeUnit : CombatUnit { };
struct RangedUnit : CombatUnit { };
struct Warrior : MeleeUnit { };
struct Wizard : RangedUnit { };
struct Marksman : RangedUnit { };
// Player/Platoon tags
struct Player { };
struct Platoon { };
static const int PlayerCount = 100;
static const int PlatoonsPerPlayer = 3;
int main(int, char *[]) {
flecs::world ecs;
// See component_inheritance example
ecs.component<CombatUnit>().is_a<Unit>();
ecs.component<MeleeUnit>().is_a<CombatUnit>();
ecs.component<RangedUnit>().is_a<CombatUnit>();
ecs.component<Warrior>().is_a<MeleeUnit>();
ecs.component<Wizard>().is_a<RangedUnit>();
ecs.component<Marksman>().is_a<RangedUnit>();
// Populate store with players and platoons
for (int p = 0; p < PlayerCount; p ++) {
flecs::entity player;
// Give first player a name so we can look it up later
if (p == 0) {
player = ecs.entity("MyPlayer");
} else {
player = ecs.entity();
}
// Add player tag so we can query for all players if we want to
player.add<Player>();
for (int pl = 0; pl < PlatoonsPerPlayer; pl ++) {
flecs::entity platoon = ecs.entity().add<Player>(player);
// Add platoon tag so we can query for all platoons if we want to
platoon.add<Platoon>();
// Add warriors, wizards and marksmen to the platoon
ecs.entity().add<Warrior>().add<Platoon>(platoon);
ecs.entity().add<Marksman>().add<Platoon>(platoon);
ecs.entity().add<Wizard>().add<Platoon>(platoon);
}
}
// Create a rule to find all RangedUnits for a platoon/player. The
// equivalent query in the query DSL would look like this:
// (Platoon, $Platoon), Player($Platoon, $Player)
//
// The way to read how this query is evaluated is:
// - find all entities with (Platoon, *), store * in _Platoon
// - check if _Platoon has (Player, *), store * in _Player
flecs::rule<RangedUnit> r = ecs.rule_builder<RangedUnit>()
.with<Platoon>().second("$Platoon")
.with<Player>("$Player").src("$Platoon")
.build();
// If we would iterate this rule it would return all ranged units for all
// platoons & for all players. We can limit the results to just a single
// platoon or a single player setting a variable beforehand. In this example
// we'll just find all platoons & ranged units for a single player.
int player_var = r.find_var("Player");
int platoon_var = r.find_var("Platoon");
// Iterate rule, limit the results to units of MyPlayer
r.iter().set_var(player_var, ecs.lookup("MyPlayer"))
.each([&](flecs::iter& it, size_t index, RangedUnit) {
flecs::entity unit = it.entity(index);
std::cout << "Unit " << unit.path() << " of class "
<< it.id(1).str() << " in platoon "
<< it.get_var(platoon_var).path() << " for player "
<< it.get_var(player_var).path() << "\n";
});
r.destruct();
// Output:
// Unit ::499 of class Wizard in platoon ::496 for player ::MyPlayer
// Unit ::503 of class Wizard in platoon ::500 for player ::MyPlayer
// Unit ::507 of class Wizard in platoon ::504 for player ::MyPlayer
// Unit ::498 of class Marksman in platoon ::496 for player ::MyPlayer
// Unit ::502 of class Marksman in platoon ::500 for player ::MyPlayer
// Unit ::506 of class Marksman in platoon ::504 for player ::MyPlayer
// Try removing the set_var call, this will cause the iterator to return
// all units in all platoons for all players.
}

16
engine/libs/flecs/examples/cpp/rules/transitive_queries/include/transitive_queries.h Normal file
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#ifndef TRANSITIVE_QUERIES_H
#define TRANSITIVE_QUERIES_H
/* This generated file contains includes for project dependencies */
#include "transitive_queries/bake_config.h"
#ifdef __cplusplus
extern "C" {
#endif
#ifdef __cplusplus
}
#endif
#endif

24
engine/libs/flecs/examples/cpp/rules/transitive_queries/include/transitive_queries/bake_config.h Normal file
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@@ -0,0 +1,24 @@
/*
)
(.)
.|.
| |
_.--| |--._
.-'; ;`-'& ; `&.
\ & ; & &_/
|"""---...---"""|
\ | | | | | | | /
`---.|.|.|.---'
* This file is generated by bake.lang.c for your convenience. Headers of
* dependencies will automatically show up in this file. Include bake_config.h
* in your main project file. Do not edit! */
#ifndef TRANSITIVE_QUERIES_BAKE_CONFIG_H
#define TRANSITIVE_QUERIES_BAKE_CONFIG_H
/* Headers of public dependencies */
#include <flecs.h>
#endif

11
engine/libs/flecs/examples/cpp/rules/transitive_queries/project.json Normal file
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@@ -0,0 +1,11 @@
{
"id": "transitive_queries",
"type": "application",
"value": {
"use": [
"flecs"
],
"language": "c++",
"public": false
}
}

124
engine/libs/flecs/examples/cpp/rules/transitive_queries/src/main.cpp Normal file
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#include <transitive_queries.h>
#include <iostream>
// Transitive relationships make it possible to tell the ECS that if an entity
// has a relationship (R, X) and X has relationship (R, Y), the entity should be
// treated as if it also has (R, Y). In practice this is useful for expressing
// things like:
//
// Bob lives in SanFrancisco
// San Francisco is located in the United States
// Therefore Bob also lives in the United States.
//
// An example of transitivity can be seen in the component_inheritance example.
// This example uses the builtin IsA relationship, which is transitive. This
// example shows how to achieve similar behavior with a user-defined relationship.
struct LocatedIn { };
struct Planet { };
struct Continent { };
struct Country { };
struct State { };
struct City { };
struct Person { };
int main(int, char *[]) {
flecs::world ecs;
// Register the LocatedIn relationship as transitive
ecs.component<LocatedIn>().add(flecs::Transitive);
// Populate the store with locations
flecs::entity earth = ecs.entity("Earth")
.add<Planet>();
// Continents
flecs::entity north_america = ecs.entity("NorthAmerica")
.add<Continent>()
.add<LocatedIn>(earth);
flecs::entity europe = ecs.entity("Europe")
.add<Continent>()
.add<LocatedIn>(earth);
// Countries
flecs::entity united_states = ecs.entity("UnitedStates")
.add<Country>()
.add<LocatedIn>(north_america);
flecs::entity netherlands = ecs.entity("Netherlands")
.add<Country>()
.add<LocatedIn>(europe);
// States
flecs::entity california = ecs.entity("California")
.add<State>()
.add<LocatedIn>(united_states);
flecs::entity washington = ecs.entity("Washington")
.add<State>()
.add<LocatedIn>(united_states);
flecs::entity noord_holland = ecs.entity("NoordHolland")
.add<State>()
.add<LocatedIn>(netherlands);
// Cities
flecs::entity san_francisco = ecs.entity("SanFrancisco")
.add<City>()
.add<LocatedIn>(california);
flecs::entity seattle = ecs.entity("Seattle")
.add<City>()
.add<LocatedIn>(washington);
flecs::entity amsterdam = ecs.entity("Amsterdam")
.add<City>()
.add<LocatedIn>(noord_holland);
// Inhabitants
ecs.entity("Bob")
.add<Person>()
.add<LocatedIn>(san_francisco);
ecs.entity("Alice")
.add<Person>()
.add<LocatedIn>(seattle);
ecs.entity("Job")
.add<Person>()
.add<LocatedIn>(amsterdam);
// Create a query that finds the countries persons live in. Note that these
// have not been explicitly added to the Person entities, but because the
// LocatedIn is transitive, the rule engine will traverse the relationship
// until it found something that is a country.
//
// The equivalent of this query in the DSL is:
// Person, (LocatedIn, $Location), Country($Location)
flecs::rule<> r = ecs.rule_builder()
.with<Person>()
.with<LocatedIn>("$Location")
.with<Country>().src("$Location")
.build();
// Lookup the index of the variable. This will let us quickly lookup its
// value while we're iterating.
int location_var = r.find_var("Location");
// Iterate the rule
r.each([&](flecs::iter& it, size_t index) {
std::cout
<< it.entity(index).name()
<< " lives in " << it.get_var(location_var).name()
<< "\n";
});
// Rules need to be explicitly deleted.
r.destruct();
// Output:
// Bob lives in UnitedStates
// Alice lives in UnitedStates
// Job lives in Netherlands
}