Start abstracting the rendering backend away to make it easier to switch to GPU rendering later

include/akgl/game.h

@@ -5,6 +5,7 @@
 #include "types.h"
 #include <SDL3_mixer/SDL_mixer.h>
 #include "tilemap.h"
+#include "renderer.h"
 
 #define AKGL_VERSION                     "0.1.0"
 
@@ -41,13 +42,13 @@ typedef struct {
 } akgl_Game;
 
 extern SDL_Window *window;
-extern SDL_Renderer *renderer;
 extern akgl_Tilemap gamemap;
 extern MIX_Audio *bgm;
 extern MIX_Mixer *akgl_mixer;
 extern MIX_Track *akgl_tracks[AKGL_GAME_AUDIO_MAX_TRACKS];
 extern SDL_FRect camera;
 extern akgl_Game game;
+extern akgl_RenderBackend renderer;
 
 #define AKGL_BITMASK_HAS(x, y) (x & y) == y
 #define AKGL_BITMASK_ADD(x, y) x |= y