Properly link flecs library

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

@@ -0,0 +1,53 @@
+#include <basics.h>
+#include <iostream>
+
+struct Position {
+    double x, y;
+};
+
+struct Walking { };
+
+int main(int, char *[]) {
+    flecs::world ecs;
+
+    // Create an entity with name Bob
+    flecs::entity bob = ecs.entity("Bob")
+        // The set operation finds or creates a component, and sets it.
+        // Components are automatically registered with the world.
+        .set<Position>({10, 20}) 
+        // The add operation adds a component without setting a value. This is
+        // useful for tags, or when adding a component with its default value.
+        .add<Walking>();
+
+    // Get the value for the Position component
+    const Position* ptr = bob.get<Position>();
+    std::cout << "{" << ptr->x << ", " << ptr->y << "}" << "\n";
+
+    // Overwrite the value of the Position component
+    bob.set<Position>({20, 30});
+
+    // Create another named entity
+    flecs::entity alice = ecs.entity("Alice")
+        .set<Position>({10, 20});
+
+    // Add a tag after entity is created
+    alice.add<Walking>();
+
+    // Print all of the components the entity has. This will output:
+    //    Position, Walking, (Identifier,Name)
+    std::cout << "[" << alice.type().str() << "]" << "\n";
+
+    // Remove tag
+    alice.remove<Walking>();
+
+    // Iterate all entities with Position
+    ecs.each([](flecs::entity e, Position& p) {
+        std::cout << e.name() << ": {" << p.x << ", " << p.y << "}" << "\n";
+    });
+
+    // Output
+    //  {10, 20}
+    //  [Position, Walking, (Identifier,Name)]
+    //  Alice: {10, 20}
+    //  Bob: {20, 30}
+}