Properly link flecs library

engine/libs/flecs/examples/c/reflection/units/src/main.c

@@ -0,0 +1,71 @@
+#include <units.h>
+#include <stdio.h>
+
+typedef struct {
+    double temperature;
+    double pressure;
+    double precipitation;
+} WeatherStation;
+
+void print_value(ecs_world_t *world, const ecs_meta_cursor_t *cur) {
+    // Get unit entity and component
+    ecs_entity_t u = ecs_meta_get_unit(cur);
+    const EcsUnit *u_data = ecs_get(world, u, EcsUnit);
+    
+    // Print value with unit symbol
+    printf("%s: %.1f %s\n", ecs_meta_get_member(cur), ecs_meta_get_float(cur),
+        u_data->symbol);
+}
+
+int main(int argc, char *argv[]) {
+    ecs_world_t *ecs = ecs_init_w_args(argc, argv);
+
+    // Import units module.
+    ECS_IMPORT(ecs, FlecsUnits);
+
+    ECS_COMPONENT(ecs, WeatherStation);
+
+    // Register reflection data with units. This can improve the way information
+    // is visualized in tools, such as the explorer.
+    ecs_struct(ecs, {
+        .entity = ecs_id(WeatherStation),
+        .members = {
+            {
+                .name = "temperature", 
+                .type = ecs_id(ecs_f64_t), 
+                .unit = EcsCelsius 
+            },
+            { 
+                .name = "pressure", 
+                .type = ecs_id(ecs_f64_t), 
+                .unit = EcsBar 
+            },
+            {
+                .name = "precipitation", 
+                .type = ecs_id(ecs_f64_t), 
+                .unit = EcsMilliMeters 
+            },
+        }
+    });
+
+    ecs_entity_t e = ecs_set(ecs, 0, WeatherStation, {24, 1.2, 0.5});
+
+    // Use cursor API to print values with units
+    WeatherStation *ptr = ecs_get_mut(ecs, e, WeatherStation);
+    ecs_meta_cursor_t cur = ecs_meta_cursor(ecs, ecs_id(WeatherStation), ptr);
+
+    ecs_meta_push(&cur);
+    print_value(ecs, &cur);
+    ecs_meta_next(&cur);
+    print_value(ecs, &cur);
+    ecs_meta_next(&cur);
+    print_value(ecs, &cur);
+    ecs_meta_pop(&cur);
+
+    return ecs_fini(ecs);
+
+    // Output:
+    //  temperature: 24.0 °C
+    //  pressure: 1.2 bar
+    //  precipitation: 0.5 mm
+}