Introduce the possiblity to draw certain frames with alpha blending on top of

an existing background. It's not supported by many frame types yet, but BButton
and TextControl frames work as well as the soft recessed frame which many
controls use.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29762 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/os/interface/ControlLook.h

@@ -61,7 +61,9 @@ public:
 		B_ACTIVATED			= 1 << 2,
 		B_HOVER				= 1 << 3,
 		B_DISABLED			= 1 << 4,
-		B_DEFAULT_BUTTON	= 1 << 5
+		B_DEFAULT_BUTTON	= 1 << 5,
+
+		B_BLEND_FRAME		= 1 << 16
 	};
 
 	virtual BAlignment			DefaultLabelAlignment() const;
@@ -253,6 +255,7 @@ protected:
 									BRect& rect, const rgb_color& base,
 									float contrast = 1.0f,
 									float brightness = 1.0f,
+									uint32 flags = 0,
 									uint32 borders = B_ALL_BORDERS);
 
 			void				_DrawFrame(BView* view, BRect& rect,