MILESTONE: bitmap showing with key color transparency implemented!

- SurfaceKeyColored class handles blitting of keycolor transparency data
- ImageMap tested - Rect and Polygon areas seem to be working as expected

svn-id: r32950

3 files changed, 47 insertions, 1 deletions

diff --git a/graphics/module.mk b/graphics/module.mk
index 93e2db26c5..a44042a044 100644
--- a/graphics/module.mk
+++ b/graphics/module.mk
@@ -16,7 +16,8 @@ MODULE_OBJS := \
 	primitives.o \
 	scaler.o \
 	scaler/thumbnail.o \
-	surface.o
+	surface.o \
+	surface-keycolored.o
 
 ifndef DISABLE_SCALERS
 MODULE_OBJS += \
diff --git a/graphics/surface-keycolored.cpp b/graphics/surface-keycolored.cpp
new file mode 100644
index 0000000000..79beb5d5b5
--- /dev/null
+++ b/graphics/surface-keycolored.cpp
@@ -0,0 +1,28 @@
+#include "graphics/surface-keycolored.h"
+
+namespace Graphics {
+
+void SurfaceKeyColored::blit(Surface *surf_src, int16 x, int16 y, OverlayColor trans) {
+	
+	if (bytesPerPixel != sizeof(OverlayColor) || surf_src->bytesPerPixel != sizeof(OverlayColor)) return ;
+
+	OverlayColor *dst = (OverlayColor*) getBasePtr(x, y);
+	const OverlayColor *src = (const OverlayColor*)surf_src->pixels;
+
+	int blitW = (surf_src->w + x > w) ? w - x : surf_src->w;
+	int blitH = (surf_src->h + y > h) ? h - y : surf_src->h;
+	int dstAdd = w - blitW;
+	int srcAdd = surf_src->w - blitW;
+
+	for (int i = 0; i < blitH; ++i) { 
+		for (int j = 0; j < blitW; ++j, ++dst, ++src) { 
+			OverlayColor col = *src;
+			if (col != trans)
+				*dst = col;
+		}
+		dst += dstAdd;
+		src += srcAdd; 
+	}
+}
+
+} // end of namespace Graphics
\ No newline at end of file
diff --git a/graphics/surface-keycolored.h b/graphics/surface-keycolored.h
new file mode 100644
index 0000000000..d2788b204e
--- /dev/null
+++ b/graphics/surface-keycolored.h
@@ -0,0 +1,17 @@
+
+#ifndef GRAPHICS_SURFACE_KEYCOLORED_H
+#define GRAPHICS_SURFACE_KEYCOLORED_H
+
+#include "graphics/surface.h"
+
+namespace Graphics {
+
+struct SurfaceKeyColored : Surface {
+
+	void blit(Surface *surf_src, int16 x, int16 y, OverlayColor trans);
+};
+
+
+} // end of namespace Graphics
+
+#endif
\ No newline at end of file