(svn r10132) -Codechange: split out the last direct video-buffer read access to the blitter-layer

-Add: added a new renderer and blitter to make room for some optimized bpp
-Fix: fill the alpha channel in the grf-spriteloader

src/blitter/8bpp_optimized.cpp

@@ -102,6 +102,16 @@ void Blitter_8bppOptimized::Draw(Blitter::BlitterParams *bp, BlitterMode mode, Z
 	}
 }
 
+void Blitter_8bppOptimized::DrawColorMappingRect(void *dst, int width, int height, int pal)
+{
+	const uint8 *ctab = GetNonSprite(pal) + 1;
+
+	do {
+		for (int i = 0; i != width; i++) _screen.renderer->SetPixel(dst, i, 0, ctab[((uint8 *)dst)[i]]);
+		dst = _screen.renderer->MoveTo(dst, 0, 1);
+	} while (height--);
+}
+
 Sprite *Blitter_8bppOptimized::Encode(SpriteLoader::Sprite *sprite, Blitter::AllocatorProc *allocator)
 {
 	Sprite *dest_sprite;