GRAPHICS: Add interface for horizontal shake

2 files changed, 12 insertions, 10 deletions

diff --git a/backends/graphics/surfacesdl/surfacesdl-graphics.cpp b/backends/graphics/surfacesdl/surfacesdl-graphics.cpp
index 92540d93f7..95c7ddc918 100644
--- a/backends/graphics/surfacesdl/surfacesdl-graphics.cpp
+++ b/backends/graphics/surfacesdl/surfacesdl-graphics.cpp
@@ -158,7 +158,7 @@ SurfaceSdlGraphicsManager::SurfaceSdlGraphicsManager(SdlEventSource *sdlEventSou
 	_scalerProc(0), _screenChangeCount(0),
 	_mouseData(nullptr), _mouseSurface(nullptr),
 	_mouseOrigSurface(nullptr), _cursorDontScale(false), _cursorPaletteDisabled(true),
-	_currentShakePos(0),
+	_currentShakeXOffset(0), _currentShakeYOffset(0),
 	_paletteDirtyStart(0), _paletteDirtyEnd(0),
 	_screenIsLocked(false),
 	_graphicsMutex(0),
@@ -822,7 +822,8 @@ int SurfaceSdlGraphicsManager::getStretchMode() const {
 void SurfaceSdlGraphicsManager::initSize(uint w, uint h, const Graphics::PixelFormat *format) {
 	assert(_transactionMode == kTransactionActive);
 
-	_gameScreenShakeOffset = 0;
+	_gameScreenShakeXOffset = 0;
+	_gameScreenShakeYOffset = 0;
 
 #ifdef USE_RGB_COLOR
 	//avoid redundant format changes
@@ -1206,16 +1207,16 @@ void SurfaceSdlGraphicsManager::internUpdateScreen() {
 	// If the shake position changed, fill the dirty area with blackness
 	// When building with SDL2, the shake offset is added to the active rect instead,
 	// so this isn't needed there.
-	if (_currentShakePos != _gameScreenShakeOffset ||
-		(_cursorNeedsRedraw && _mouseBackup.y <= _currentShakePos)) {
-		SDL_Rect blackrect = {0, 0, (Uint16)(_videoMode.screenWidth * _videoMode.scaleFactor), (Uint16)(_gameScreenShakeOffset * _videoMode.scaleFactor)};
+	if (_currentShakeYOffset != _gameScreenShakeYOffset ||
+		(_cursorNeedsRedraw && _mouseBackup.y <= _currentShakeYOffset)) {
+		SDL_Rect blackrect = {0, 0, (Uint16)(_videoMode.screenWidth * _videoMode.scaleFactor), (Uint16)(_gameScreenShakeYOffset * _videoMode.scaleFactor)};
 
 		if (_videoMode.aspectRatioCorrection && !_overlayVisible)
 			blackrect.h = real2Aspect(blackrect.h - 1) + 1;
 
 		SDL_FillRect(_hwScreen, &blackrect, 0);
 
-		_currentShakePos = _gameScreenShakeOffset;
+		_currentShakeYOffset = _gameScreenShakeYOffset;
 
 		_forceRedraw = true;
 	}
@@ -1293,7 +1294,7 @@ void SurfaceSdlGraphicsManager::internUpdateScreen() {
 		dstPitch = _hwScreen->pitch;
 
 		for (r = _dirtyRectList; r != lastRect; ++r) {
-			int dst_y = r->y + _currentShakePos;
+			int dst_y = r->y + _currentShakeYOffset;
 			int dst_h = 0;
 #ifdef USE_SCALERS
 			int orig_dst_y = 0;
@@ -1349,7 +1350,7 @@ void SurfaceSdlGraphicsManager::internUpdateScreen() {
 		// Of course when the overlay is visible we do not show it, since it is only for game
 		// specific focus.
 		if (_enableFocusRect && !_overlayVisible) {
-			int y = _focusRect.top + _currentShakePos;
+			int y = _focusRect.top + _currentShakeYOffset;
 			int h = 0;
 			int x = _focusRect.left * scale1;
 			int w = _focusRect.width() * scale1;
@@ -2276,7 +2277,7 @@ void SurfaceSdlGraphicsManager::drawMouse() {
 	// We draw the pre-scaled cursor image, so now we need to adjust for
 	// scaling, shake position and aspect ratio correction manually.
 
-	dst.y += _currentShakePos;
+	dst.y += _currentShakeYOffset;
 
 	if (_videoMode.aspectRatioCorrection && !_overlayVisible)
 		dst.y = real2Aspect(dst.y);
diff --git a/backends/graphics/surfacesdl/surfacesdl-graphics.h b/backends/graphics/surfacesdl/surfacesdl-graphics.h
index a51aa22e9b..6b8ae36b87 100644
--- a/backends/graphics/surfacesdl/surfacesdl-graphics.h
+++ b/backends/graphics/surfacesdl/surfacesdl-graphics.h
@@ -387,7 +387,8 @@ protected:
 
 	// Shake mode
 	// This is always set to 0 when building with SDL2.
-	int _currentShakePos;
+	int _currentShakeXOffset;
+	int _currentShakeYOffset;
 
 	// Palette data
 	SDL_Color *_currentPalette;