prefab_design.c

typedef struct Radar {
	float range;
	float speed;
} Radar;

void SetRadar(ecs_rows_t *rows) {
	ECS_COLUMN(rows, Radar, radar, 1);
	ECS_COLUMN_COMPONENT(rows, EcsCircle, 2);
	ECS_COLUMN_COMPONENT(rows, EcsAngularMomentum2D, 3);
	ECS_COLUMN_COMPONENT(rows, EcsLine, 4);

	for (int i = 0; i < rows->count; i ++) {
		ecs_entity_t radar = rows->entities[i];
		ecs_entity_t range = ecs_lookup_child(world, radar, "RadarRange");
		ecs_entity_t sweep = ecs_lookup_child(word, radar, "RadarSweep");

		ecs_set(rows->world, range, EcsCircle, {radar[i].range});
		ecs_set(rows->world, sweep, EcsAngularMomentum2D, {radar[i].speed});
		ecs_set(rows->world, sweep, EcsLine, {0, 0}, {0, radar[i].range});
	}
}

int main(int argc, char *argv) {
	ecs_world_t *world = ecs_init();

	/* Radar prefab */
	ECS_ENTITY(world, RadarPrefab, 
		EcsPrefab,
			Radar: {range: 0},
			EcsPosition2D: {0, 0});

	ECS_ENTITY(world, RadarRange,
		EcsPrefab: {parent: RadarPrefab},
			EcsPosition2D: {0, 0},
			EcsCircle: {0});

	ECS_ENTITY(world, RadarSweep,
		EcsPrefab: {parent: RadarPrefab},
			EcsPosition2D: {0, 0},
			EcsRotation2D: {0},
			EcsAngularMomentum2D: {0},
			EcsLine: {{0, 0}, {0, 0}});

	ECS_SYSTEM(world, SetRadar, EcsOnSet, Radar,
		ID.EcsCircle, 
		ID.EcsAngularMomentum2D,
		ID.EcsLine);

	ECS_SYSTEM(world, UpdateRadar, EcsOnUpdate, Radar);


	/* Ship prefab */
	ECS_ENTITY(world, ShipPrefab,
		EcsPrefab,
			EcsPosition2D: {0, 0},
			EcsRotatino2D: {0, 0},
			EcsCircle: {0, 0});

	ECS_ENTITY(world, ShipRadar, RadarPrefab
		EcsPrefab: {.parent = ShipPrefab},
			Radar: {range: 100});

	/* Plane prefab */
	ECS_ENTITY(world, PlanePrefab,
		EcsPrefab,
			EcsPosition2D: {0, 0},
			EcsRotatino2D: {0, 0},
			EcsCircle: {0, 0});

	ECS_ENTITY(world, PlaneRadar, RadarPrefab
		EcsPrefab: {parent: PlanePrefab},
			Radar: {range: 50});

}