Added two new methods to OSystem: grabPalette and grabRawScreen

svn-id: r17974

3 files changed, 62 insertions, 0 deletions

diff --git a/backends/sdl/graphics.cpp b/backends/sdl/graphics.cpp
index 658a1f3739..43e1a7cd4d 100644
--- a/backends/sdl/graphics.cpp
+++ b/backends/sdl/graphics.cpp
@@ -25,6 +25,7 @@
 #include "common/util.h"
 #include "graphics/font.h"
 #include "graphics/fontman.h"
+#include "graphics/surface.h"
 
 static const OSystem::GraphicsMode s_supportedGraphicsModes[] = {
 	{"1x", "Normal (no scaling)", GFX_NORMAL},
@@ -821,6 +822,25 @@ void OSystem_SDL::copyRectToScreen(const byte *src, int pitch, int x, int y, int
 	SDL_UnlockSurface(_screen);
 }
 
+bool OSystem_SDL::grabRawScreen(Graphics::Surface *surf) {
+	assert(_screen);
+	assert(surf);
+	
+	Common::StackLock lock(_graphicsMutex);	// Lock the mutex until this function ends
+	
+	surf->create(_screenWidth, _screenHeight, _screen->format->BytesPerPixel);
+	
+	// Try to lock the screen surface
+	if (SDL_LockSurface(_screen) == -1)
+		error("SDL_LockSurface failed: %s", SDL_GetError());
+	
+	memcpy(surf->pixels, _screen->pixels, _screenWidth * _screenHeight * _screen->format->BytesPerPixel);
+	
+	// Unlock the screen surface
+	SDL_UnlockSurface(_screen);
+	
+	return true;
+}
 
 void OSystem_SDL::addDirtyRect(int x, int y, int w, int h, bool mouseRect) {
 	if (_forceFull)
@@ -1007,6 +1027,18 @@ void OSystem_SDL::setPalette(const byte *colors, uint start, uint num) {
 		blitCursor();
 }
 
+void OSystem_SDL::grabPalette(byte *colors, uint start, uint num) {
+	assert(colors);	
+	const SDL_Color *base = _currentPalette + start;
+	
+	for (uint i = 0; i < num; ++i) {
+		colors[i * 4] = base[i].r;
+		colors[i * 4 + 1] = base[i].g;
+		colors[i * 4 + 2] = base[i].b;
+		colors[i * 4 + 3] = 0xFF;
+	}
+}
+
 void OSystem_SDL::setCursorPalette(const byte *colors, uint start, uint num) {
 	assert(colors);
 	const byte *b = colors;
diff --git a/backends/sdl/sdl-common.h b/backends/sdl/sdl-common.h
index 2d3337e0d5..a4265c6f31 100644
--- a/backends/sdl/sdl-common.h
+++ b/backends/sdl/sdl-common.h
@@ -80,11 +80,17 @@ public:
 
 	// Set colors of the palette
 	void setPalette(const byte *colors, uint start, uint num);
+	
+	// Get colors of the palette
+	void grabPalette(byte *colors, uint start, uint num);
 
 	// Draw a bitmap to screen.
 	// The screen will not be updated to reflect the new bitmap
 	void copyRectToScreen(const byte *src, int pitch, int x, int y, int w, int h);
 
+	// Copies the screen to a buffer
+	bool grabRawScreen(Graphics::Surface *surf);
+
 	// Clear the screen
 	void clearScreen();
 
diff --git a/common/system.h b/common/system.h
index 262a88c3b9..63d50530ce 100644
--- a/common/system.h
+++ b/common/system.h
@@ -28,6 +28,10 @@
 #include "common/rect.h"
 #include "common/singleton.h"
 
+namespace Graphics {
+class Surface;
+} // end of namespace Graphics
+
 class SaveFileManager;
 
 /**
@@ -361,6 +365,16 @@ public:
 	 *       API are probably going to remove it.
 	 */
 	virtual void setPalette(const byte *colors, uint start, uint num) = 0;
+	
+	/**
+	 * Grabs a specified part of the currently active palette.
+	 * The format is the same as for setPalette.
+	 *
+	 * @param buf	the buffer
+	 * @param start	the first platte entry
+	 * @param num	nummber of the entries
+	 */
+	virtual void grabPalette(byte *colors, uint start, uint num) = 0;
 
 	/**
 	 * Blit a bitmap to the virtual screen.
@@ -371,6 +385,16 @@ public:
 	 * @see updateScreen
 	 */
 	virtual void copyRectToScreen(const byte *buf, int pitch, int x, int y, int w, int h) = 0;
+
+	/**
+	 * Copies the current screen contents to a new surface, with the original
+	 * bit depth. This will allocate memory for the pixel data.
+	 * WARNING: surf->free() must be called by the user to avoid leaking.
+	 *
+	 * @param surf	the surfce to store the data in it
+	 * @return true if all went well, false if an error occured
+	 */
+	virtual bool grabRawScreen(Graphics::Surface *surf) { return false; }
 	
 	/**
 	 * Clear the screen to black.