Properly link flecs library

engine/libs/flecs/examples/cpp/entities/prefab/.gitignore

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+.bake_cache
+.DS_Store
+.vscode
+gcov
+bin

engine/libs/flecs/examples/cpp/entities/prefab/include/prefab.h

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+#ifndef PREFAB_H
+#define PREFAB_H
+
+/* This generated file contains includes for project dependencies */
+#include "prefab/bake_config.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+

engine/libs/flecs/examples/cpp/entities/prefab/include/prefab/bake_config.h

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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 PREFAB_BAKE_CONFIG_H
+#define PREFAB_BAKE_CONFIG_H
+
+/* Headers of public dependencies */
+#include <flecs.h>
+
+#endif
+

engine/libs/flecs/examples/cpp/entities/prefab/project.json

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+{
+    "id": "prefab",
+    "type": "application",
+    "value": {
+        "author": "Jane Doe",
+        "description": "A simple hello world flecs application",
+        "use": [
+            "flecs"
+        ],
+        "language": "c++"
+    }
+}

engine/libs/flecs/examples/cpp/entities/prefab/src/main.cpp

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+#include <prefab.h>
+#include <iostream>
+
+// Prefabs are entities that can be used as templates for other entities. They
+// are created with a builtin Prefab tag, which by default excludes them from
+// queries and systems.
+
+struct Attack { double value; };
+struct Defense { double value; };
+struct FreightCapacity { double value; };
+struct ImpulseSpeed { double value; };
+struct HasFTL { };
+
+struct Position { double x = 0; double y = 0; };
+
+int main(int, char *[]) {
+    flecs::world ecs;
+
+    // Create a prefab hierarchy.
+    flecs::entity spaceship = ecs.prefab("Spaceship")
+        // Add components to prefab entity as usual
+        .set<ImpulseSpeed>({50})
+        .set<Defense>({50})
+
+        // By default components in an inheritance hierarchy are shared between
+        // entities. The override function ensures that instances have a private
+        // copy of the component.
+        .override<Position>();
+
+        flecs::entity freighter = ecs.prefab("Freighter")
+            // Short for .add(flecs::IsA, spaceship). This ensures the entity
+            // inherits all components from spaceship.
+            .is_a(spaceship)
+            .add<HasFTL>()
+            .set<FreightCapacity>({100})
+            .set<Defense>({100});
+
+            flecs::entity mammoth_freighter = ecs.prefab("MammothFreighter")
+                .is_a(freighter)
+                .set<FreightCapacity>({500})
+                .set<Defense>({300});
+
+        ecs.prefab("Frigate")
+            .is_a(spaceship)
+            .add<HasFTL>()
+            .set<Attack>({100})
+            .set<Defense>({75})
+            .set<ImpulseSpeed>({125});
+
+    // Create a regular entity from a prefab.
+    // The instance will have a private copy of the Position component, because
+    // of the override in the spaceship entity. All other components are shared.
+    flecs::entity inst = ecs.entity("my_mammoth_freighter")
+        .is_a(mammoth_freighter);
+
+    // Inspect the type of the entity. This outputs:
+    //    Position,(Identifier,Name),(IsA,MammothFreighter)
+    std::cout << "Instance type: [" << inst.type().str() << "]\n";
+
+    // Even though the instance doesn't have a private copy of ImpulseSpeed, we
+    // can still get it using the regular API (outputs 50)
+    const ImpulseSpeed *ptr = inst.get<ImpulseSpeed>();
+    std::cout << "Impulse speed: " << ptr->value << "\n";
+
+    // Prefab components can be iterated just like regular components:
+    ecs.each([](flecs::entity e, ImpulseSpeed& is, Position& p) {
+        p.x += is.value;
+        std::cout << e.name() << ": {" << p.x << ", " << p.y << "}\n"; 
+    });
+}