Add frame advance

src/gba/gba-thread.c

@@ -291,6 +291,11 @@ void GBASyncPostFrame(struct GBASync* sync) {
 		}
 	}
 	MutexUnlock(&sync->videoFrameMutex);
+
+	struct GBAThread* thread = GBAThreadGetContext();
+	if (thread->frameCallback) {
+		thread->frameCallback(thread);
+	}
 }
 
 int GBASyncWaitFrameStart(struct GBASync* sync, int frameskip) {

src/gba/gba-thread.h

@@ -36,6 +36,7 @@ struct GBAThread {
 
 	ThreadCallback startCallback;
 	ThreadCallback cleanCallback;
+	ThreadCallback frameCallback;
 	void* userData;
 
 	struct GBASync {

src/platform/sdl/gl-main.c

@@ -73,6 +73,7 @@ int main(int argc, char** argv) {
 	context.sync.audioWait = 1;
 	context.startCallback = _GBASDLStart;
 	context.cleanCallback = _GBASDLClean;
+	context.frameCallback = 0;
 	context.userData = &renderer;
 	GBAThreadStart(&context);
 

src/platform/sdl/sdl-events.c

@@ -11,6 +11,7 @@ int GBASDLInitEvents(struct GBASDLEvents* context) {
 	}
 	SDL_JoystickEventState(SDL_ENABLE);
 	context->joystick = SDL_JoystickOpen(0);
+	SDL_EnableKeyRepeat(SDL_DEFAULT_REPEAT_DELAY, SDL_DEFAULT_REPEAT_INTERVAL);
 	return 1;
 }
 
@@ -19,6 +20,11 @@ void GBASDLDeinitEvents(struct GBASDLEvents* context) {
 	SDL_QuitSubSystem(SDL_INIT_JOYSTICK);
 }
 
+static void _pauseAfterFrame(struct GBAThread* context) {
+	context->frameCallback = 0;
+	GBAThreadPause(context);
+}
+
 static void _GBASDLHandleKeypress(struct GBAThread* context, const struct SDL_KeyboardEvent* event) {
 	enum GBAKey key = 0;
 	switch (event->keysym.sym) {
@@ -68,6 +74,12 @@ static void _GBASDLHandleKeypress(struct GBAThread* context, const struct SDL_Ke
 				switch (event->keysym.sym) {
 				case SDLK_p:
 					GBAThreadTogglePause(context);
+					break;
+				case SDLK_n:
+					GBAThreadPause(context);
+					context->frameCallback = _pauseAfterFrame;
+					GBAThreadUnpause(context);
+					break;
 				default:
 					break;
 				}