Implemented the OSystem framebuffer API, as discussed on scummvm-devel. All changes are just fine, and won't cause any compile problems or regressions, despite the fact that I can't test most of the non-SDL backend changes, at an improbability level of two to the power of two hundred and seventy-six thousand to one against - possibly much higher. Anything you still can't cope with is therefore your own problem. Please relax.

svn-id: r27548

2 files changed, 20 insertions, 13 deletions

diff --git a/backends/platform/dc/dc.h b/backends/platform/dc/dc.h
index 01e86a561b..fa47ed21f5 100644
--- a/backends/platform/dc/dc.h
+++ b/backends/platform/dc/dc.h
@@ -81,8 +81,8 @@ class OSystem_Dreamcast : public OSystem {
   // The screen will not be updated to reflect the new bitmap
   void copyRectToScreen(const byte *buf, int pitch, int x, int y, int w, int h);
 
-  // Copies the current screen contents to a new surface.
-  bool grabRawScreen(Graphics::Surface *surf);
+	virtual Graphics::Surface *lockScreen();
+	virtual void unlockScreen();
 
   // Clear the screen to black.
   void clearScreen();
@@ -213,6 +213,8 @@ class OSystem_Dreamcast : public OSystem {
   void *ovl_tx[NUM_BUFFERS];
   unsigned short palette[256], cursor_palette[256];
 
+  Graphics::Surface _framebuffer;
+
   int temp_sound_buffer[RING_BUFFER_SAMPLES>>SOUND_BUFFER_SHIFT];
 
   void checkSound();
diff --git a/backends/platform/dc/display.cpp b/backends/platform/dc/display.cpp
index 73312cafed..da9f6e83ff 100644
--- a/backends/platform/dc/display.cpp
+++ b/backends/platform/dc/display.cpp
@@ -609,19 +609,24 @@ int OSystem_Dreamcast::getGraphicsMode() const
   return 0;
 }
 
-bool OSystem_Dreamcast::grabRawScreen(Graphics::Surface *surf)
+Graphics::Surface *OSystem_Dreamcast::lockScreen()
 {
-  if(!screen || !surf)
-    return false;
+  if (!screen)
+    return 0;
 
-  surf->create(_screen_w, _screen_h, 1);
-  unsigned char *src = screen, *dst = (unsigned char *)surf->pixels;
-  for(int h = _screen_h; h>0; --h) {
-    memcpy(dst, src, _screen_w);
-    src += SCREEN_W;
-    dst += _screen_w;
-  }
-  return true;
+  _framebuffer.pixels = screen;
+  _framebuffer.w = _screen_w;
+  _framebuffer.h = _screen_h;
+  _framebuffer.pitch = SCREEN_W;
+  _framebuffer.bytesPerPixel = 1;
+
+  return &_framebuffer;
+}
+
+void OSystem_Dreamcast::unlockScreen()
+{
+  // Force screen update
+  _screen_dirty = true;
 }
 
 void OSystem_Dreamcast::clearScreen()