Fix textures/font lifetimes

include/window/window.h

@@ -7,18 +7,39 @@
 struct Image {
   SDL_Texture *texture;
   Vec2<float> size;
+
+  ~Image() {
+    SDL_DestroyTexture(texture);
+  }
 };
 
 struct Font {
   TTF_Font *font;
   bool pixel_art;
+
+  ~Font() {
+    TTF_CloseFont(font);
+  }
 };
 
 struct Text {
   SDL_Texture *texture;
   Vec2<float> size;
+
+  ~Text() {
+    SDL_DestroyTexture(texture);
+  }
 };
 
+// Image pool
+inline Pool<Image> image_pool;
+
+// Font pool
+inline Pool<Font> font_pool;
+
+// Text pool
+inline Pool<Text> text_pool;
+
 struct Event {
   enum Type {
     NONE,
@@ -63,6 +84,11 @@ struct Animation {
   float frame_rate;
   bool loop;
   int reference_count = 0;
+
+  ~Animation() {
+    for (int frame_id : frames)
+      image_pool.release(frame_id);
+  }
 };
 
 inline Pool<Animation> animation_pool;
@@ -78,17 +104,12 @@ public:
 
   // Rendering functions
   int load_image(const char *path, float alpha = 1.0f, bool pixel_art = false);
-  void use_image(int image_id);
-  void unload_image(int image_id);
   Vec2<float> get_image_size(int image_id);
 
   int load_font(const char *path, int font_size, bool bold = false, bool italic = false, bool underline = false, bool pixel_art = false);
-  void use_font(int font_id);
-  void unload_font(int font_id);
 
   // text is copied internally, so it can be free'd by the caller after the text is created.
   int create_text(int font_id, const char *text, uint32_t length, Color color);
-  void unload_text(int text_id);
   Vec2<float> get_text_size(int text_id);
 
   bool write(int text_id, Vec2<float> position, float z, float angle = 0.0f, Vec2<float> scale = {1.0f, 1.0f});
@@ -138,15 +159,6 @@ private:
   // White pixel texture for drawing colored rectangles
   SDL_Texture *white_tex;
 
-  // Image pool
-  Pool<Image> image_pool;
-
-  // Font pool
-  Pool<Font> font_pool;
-
-  // Text pool
-  Pool<Text> text_pool;
-
   struct RenderInstruction {
     enum Type {
       DRAW_IMAGE,