Properly link flecs library

engine/libs/flecs/examples/cpp/modules/simple_module/src/main.cpp

@@ -0,0 +1,31 @@
+#include <simple_module.h>
+#include <iostream>
+
+int main(int, char *[]) {
+    flecs::world ecs;
+
+    ecs.import<simple::module>();
+
+    // Create system that uses component from module
+    ecs.system<const simple::Position>("PrintPosition")
+        .each([](const simple::Position& p) {
+            std::cout << "p = {" << p.x << ", " << p.y << "} (system)\n";
+        });
+
+    // Create entity with imported components
+    flecs::entity e = ecs.entity()
+        .set<simple::Position>({10, 20})
+        .set<simple::Velocity>({1, 1});
+
+    // Call progress which runs imported Move system
+    ecs.progress();
+
+    // Use component from module in operation
+    e.get([](const simple::Position& p) {
+        std::cout << "p = {" << p.x << ", " << p.y << "} (get)\n";
+    });
+
+    // Output:
+    //   p = {11.000000, 22.000000} (system)
+    //   p = {11.000000, 22.000000} (get)
+}

engine/libs/flecs/examples/cpp/modules/simple_module/src/simple_module.cpp

@@ -0,0 +1,26 @@
+#include <simple_module.h>
+
+namespace simple {
+
+module::module(flecs::world& ecs) {
+    // Register module with world. The module entity will be created with the
+    // same hierarchy as the C++ namespaces (e.g. simple.module)
+    ecs.module<module>();
+
+    // All contents of the module are created inside the module's namespace, so
+    // the Position component will be created as simple.module.Position
+
+    // Component registration is optional, however by registering components
+    // inside the module constructor, they will be created inside the scope
+    // of the module.
+    ecs.component<Position>();
+    ecs.component<Velocity>();
+
+    ecs.system<Position, const Velocity>("Move")
+        .each([](Position& p, const Velocity& v) {    
+            p.x += v.x;
+            p.y += v.y;
+        });        
+}
+
+}