-int layer_add_rect(Layer *layer, Rect rect, Color color);
-int layer_delete_rect_at(Layer *layer, Vec position);
-
-size_t layer_count(const Layer *layer);
-const Rect *layer_rects(const Layer *layer);
-const Color *layer_colors(const Layer *layer);
+int layer_render(LayerPtr layer, Camera *camera, int active);
+int layer_event(LayerPtr layer, const SDL_Event *event, const Camera *camera);
+int layer_dump_stream(LayerPtr layer, FILE *stream);