2 files changed, 43 insertions, 33 deletions

diff --git a/backends/platform/psp/display_manager.cpp b/backends/platform/psp/display_manager.cpp
index 5037543f12..9f58a64ee3 100644
--- a/backends/platform/psp/display_manager.cpp
+++ b/backends/platform/psp/display_manager.cpp
@@ -53,10 +53,9 @@
 uint32 __attribute__((aligned(16))) MasterGuRenderer::_displayList[2048];
 
 const OSystem::GraphicsMode DisplayManager::_supportedModes[] = {
-	{ "320x200 (centered)", "320x200 16-bit centered", CENTERED_320X200 },
-	{ "435x272 (best-fit, centered)", "435x272 16-bit centered", CENTERED_435X272 },
-	{ "480x272 (full screen)", "480x272 16-bit stretched", STRETCHED_480X272 },
-	{ "362x272 (4:3, centered)", "362x272 16-bit centered", CENTERED_362X272 },
+	{ "Original Resolution", "Original Resolution", ORIGINAL_RESOLUTION },
+	{ "Keep Aspect Ratio", "Keep Aspect Ratio", KEEP_ASPECT_RATIO },
+	{ "Full Screen", "Full Screen", STRETCHED_FULL_SCREEN },
 	{0, 0, 0}
 };
 
@@ -263,38 +262,50 @@ bool DisplayManager::setGraphicsMode(int mode) {
 
 	_graphicsMode = mode;
 
+	calculateScaleParams();
+
+	return true;
+}
+
+void DisplayManager::calculateScaleParams() {
+
+	if (!_displayParams.screenSource.width || !_displayParams.screenSource.height)
+		return; // we can't calculate anything without these
+
 	switch (_graphicsMode) {
-	case CENTERED_320X200:
-		_displayParams.screenOutput.width = 320;
-		_displayParams.screenOutput.height = 200;
-		break;
-	case CENTERED_435X272:
-		_displayParams.screenOutput.width = 435;
-		_displayParams.screenOutput.height = 272;
+	case ORIGINAL_RESOLUTION:
+		// check if we can fit the original resolution inside the screen
+		if ((_displayParams.screenSource.width < PSP_SCREEN_WIDTH) &&
+			(_displayParams.screenSource.height < PSP_SCREEN_HEIGHT)) {
+			_displayParams.screenOutput.width =  _displayParams.screenSource.width;
+			_displayParams.screenOutput.height =  _displayParams.screenSource.height;
+		} else { // revert to stretch to fit
+			_displayParams.screenOutput.width = PSP_SCREEN_WIDTH;
+			_displayParams.screenOutput.height = PSP_SCREEN_HEIGHT;
+		}
 		break;
-	case STRETCHED_480X272:
-		_displayParams.screenOutput.width = 480;
-		_displayParams.screenOutput.height = 272;
+	case KEEP_ASPECT_RATIO:	{ // maximize the height while keeping aspect ratio
+			float aspectRatio = (float)_displayParams.screenSource.width / (float)_displayParams.screenSource.height;
+			
+			_displayParams.screenOutput.height = PSP_SCREEN_HEIGHT;	// always full height
+			_displayParams.screenOutput.width = (uint32)(PSP_SCREEN_HEIGHT * aspectRatio);
+			
+			if (_displayParams.screenOutput.width > PSP_SCREEN_WIDTH) // we can't have wider than the screen
+				_displayParams.screenOutput.width = PSP_SCREEN_WIDTH;
+		}
 		break;
-	case CENTERED_362X272:
-		_displayParams.screenOutput.width = 362;
-		_displayParams.screenOutput.height = 272;
+	case STRETCHED_FULL_SCREEN:	// we simply stretch to the whole screen
+		_displayParams.screenOutput.width = PSP_SCREEN_WIDTH;
+		_displayParams.screenOutput.height = PSP_SCREEN_HEIGHT;
 		break;
 	default:
 		PSP_ERROR("Unsupported graphics mode[%d].\n", _graphicsMode);
 	}
+	
+	// calculate scale factors for X and Y
+	_displayParams.scaleX = ((float)_displayParams.screenOutput.width) / _displayParams.screenSource.width;
+	_displayParams.scaleY = ((float)_displayParams.screenOutput.height) / _displayParams.screenSource.height;
 
-	calculateScaleParams();
-
-	return true;
-}
-
-void DisplayManager::calculateScaleParams() {
-	if (_displayParams.screenOutput.width && _displayParams.screenSource.width &&
-	        _displayParams.screenOutput.height && _displayParams.screenSource.height) {
-		_displayParams.scaleX = ((float)_displayParams.screenOutput.width) / _displayParams.screenSource.width;
-		_displayParams.scaleY = ((float)_displayParams.screenOutput.height) / _displayParams.screenSource.height;
-	}
 }
 
 // return true if we really rendered or no dirty. False otherwise
diff --git a/backends/platform/psp/display_manager.h b/backends/platform/psp/display_manager.h
index 1f7320902c..f52541e615 100644
--- a/backends/platform/psp/display_manager.h
+++ b/backends/platform/psp/display_manager.h
@@ -61,10 +61,9 @@ class PSPKeyboard;
 class DisplayManager {
 public:
 	enum GraphicsModeID {			///> Possible output formats onscreen
-		CENTERED_320X200,
-		CENTERED_435X272,
-		STRETCHED_480X272,
-		CENTERED_362X272
+		ORIGINAL_RESOLUTION,
+		KEEP_ASPECT_RATIO,
+		STRETCHED_FULL_SCREEN
 	};
 	DisplayManager() : _screen(0), _cursor(0), _overlay(0), _keyboard(0), _lastUpdateTime(0), _graphicsMode(0) {}
 	~DisplayManager();
@@ -74,7 +73,7 @@ public:
 	bool setGraphicsMode(int mode);
 	bool setGraphicsMode(const char *name);
 	int getGraphicsMode() const { return _graphicsMode; }
-	uint32 getDefaultGraphicsMode() const { return STRETCHED_480X272; }
+	uint32 getDefaultGraphicsMode() const { return STRETCHED_FULL_SCREEN; }
 	const OSystem::GraphicsMode* getSupportedGraphicsModes() const { return _supportedModes; }
 
 	// Setters