GetRasterOperationCode Method
retrieves the foreground mix mode of the specified device context. The mix mode specifies how the pen or interior color and the color already on the screen are combined to yield a new color.
Return Value
If the function succeeds, the return value specifies the foreground mix mode. otherwise zero indicates failed.
Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2