Codechange: be consistent in what CheckPaletteAnim() does and when it is called

Additionally, make sure this is a class method. Later commits
will make use of this.

src/video/allegro_v.cpp

@@ -95,7 +95,7 @@ static void InitPalette()
 	UpdatePalette(0, 256);
 }
 
-static void CheckPaletteAnim()
+void VideoDriver_Allegro::CheckPaletteAnim()
 {
 	if (_cur_palette.count_dirty != 0) {
 		Blitter *blitter = BlitterFactory::GetCurrentBlitter();
@@ -484,8 +484,6 @@ void VideoDriver_Allegro::MainLoop()
 	auto next_game_tick = cur_ticks;
 	auto next_draw_tick = cur_ticks;
 
-	CheckPaletteAnim();
-
 	for (;;) {
 		InteractiveRandom(); // randomness
 
@@ -522,7 +520,7 @@ void VideoDriver_Allegro::MainLoop()
 			this->InputLoop();
 			::InputLoop();
 			UpdateWindows();
-			CheckPaletteAnim();
+			this->CheckPaletteAnim();
 
 			this->Paint();
 		}

src/video/allegro_v.h

@@ -36,6 +36,7 @@ public:
 protected:
 	void InputLoop() override;
 	void Paint() override;
+	void CheckPaletteAnim() override;
 };
 
 /** Factory for the allegro video driver. */

src/video/cocoa/cocoa_v.h

@@ -76,6 +76,7 @@ protected:
 	float GetDPIScale() override;
 	void InputLoop() override;
 	void Paint() override;
+	void CheckPaletteAnim() override;
 
 private:
 	bool PollEvent();
@@ -88,7 +89,6 @@ private:
 	bool MakeWindow(int width, int height);
 
 	void UpdatePalette(uint first_color, uint num_colors);
-	void CheckPaletteAnim();
 
 	void BlitIndexedToView32(int left, int top, int right, int bottom);
 };

src/video/sdl2_v.cpp

@@ -853,8 +853,6 @@ void VideoDriver_SDL::MainLoop()
 	last_realtime_tick = cur_ticks;
 	next_game_tick = cur_ticks;
 
-	this->CheckPaletteAnim();
-
 	if (_draw_threaded) {
 		/* Initialise the mutex first, because that's the thing we *need*
 		 * directly in the newly created thread. */

src/video/sdl2_v.h

@@ -48,6 +48,7 @@ protected:
 	void UnlockVideoBuffer() override;
 	void Paint() override;
 	void PaintThread() override;
+	void CheckPaletteAnim();
 
 private:
 	int PollEvent();
@@ -55,7 +56,6 @@ private:
 	void MainLoopCleanup();
 	bool CreateMainSurface(uint w, uint h, bool resize);
 	bool CreateMainWindow(uint w, uint h);
-	void CheckPaletteAnim();
 
 #ifdef __EMSCRIPTEN__
 	/* Convert a constant pointer back to a non-constant pointer to a member function. */

src/video/sdl_v.cpp

@@ -123,8 +123,10 @@ static void InitPalette()
 	UpdatePalette(true);
 }
 
-static void CheckPaletteAnim()
+void VideoDriver_SDL::CheckPaletteAnim()
 {
+	_local_palette = _cur_palette;
+
 	if (_cur_palette.count_dirty != 0) {
 		Blitter *blitter = BlitterFactory::GetCurrentBlitter();
 
@@ -183,7 +185,6 @@ void VideoDriver_SDL::PaintThread()
 	_draw_signal->wait(*_draw_mutex);
 
 	while (_draw_continue) {
-		CheckPaletteAnim();
 		/* Then just draw and wait till we stop */
 		this->Paint();
 		_draw_signal->wait(lock);
@@ -708,8 +709,6 @@ void VideoDriver_SDL::MainLoop()
 	auto next_game_tick = cur_ticks;
 	auto next_draw_tick = cur_ticks;
 
-	CheckPaletteAnim();
-
 	std::thread draw_thread;
 	if (_draw_threaded) {
 		/* Initialise the mutex first, because that's the thing we *need*
@@ -781,12 +780,11 @@ void VideoDriver_SDL::MainLoop()
 			this->InputLoop();
 			::InputLoop();
 			UpdateWindows();
-			_local_palette = _cur_palette;
+			this->CheckPaletteAnim();
 
 			if (_draw_mutex != nullptr && !HasModalProgress()) {
 				_draw_signal->notify_one();
 			} else {
-				CheckPaletteAnim();
 				this->Paint();
 			}
 		}

src/video/sdl_v.h

@@ -43,6 +43,7 @@ protected:
 	void UnlockVideoBuffer() override;
 	void Paint() override;
 	void PaintThread() override;
+	void CheckPaletteAnim();
 
 private:
 	std::unique_lock<std::recursive_mutex> draw_lock;

src/video/video_driver.hpp

@@ -184,6 +184,11 @@ protected:
 	 */
 	virtual void PaintThread() {}
 
+	/**
+	 * Process any pending palette animation.
+	 */
+	virtual void CheckPaletteAnim() {}
+
 	std::chrono::steady_clock::duration GetGameInterval()
 	{
 		return std::chrono::milliseconds(MILLISECONDS_PER_TICK);

src/video/win32_v.cpp

@@ -1201,7 +1201,6 @@ void VideoDriver_Win32::MainLoop()
 
 	_wnd.running = true;
 
-	CheckPaletteAnim();
 	for (;;) {
 		InteractiveRandom(); // randomness
 

src/video/win32_v.h

@@ -49,12 +49,11 @@ protected:
 	void UnlockVideoBuffer() override;
 	void Paint() override;
 	void PaintThread() override;
+	void CheckPaletteAnim() override;
 
 private:
 	std::unique_lock<std::recursive_mutex> draw_lock;
 
-	void CheckPaletteAnim();
-
 	static void PaintThreadThunk(VideoDriver_Win32 *drv);
 };