The ICM_DRAW_WINDOW message notifies a rendering driver that the window specified for the ICM_DRAW_BEGIN message needs to be redrawn. The window has moved or become temporarily obscured. You can send this message explicitly or by using the ICDrawWindow macro.
Pointer to the destination rectangle in screen coordinates. If this parameter points to an empty rectangle, drawing should be turned off.
Returns ICERR_OK if successful or an error otherwise.
This message is supported by hardware that performs its own asynchronous decompression, timing, and drawing.
Video-overlay drivers use this message to draw when the window is obscured or moved. When a window specified for ICM_DRAW_BEGIN is completely hidden by other windows, the destination rectangle is empty. Drivers should turn off video-overlay hardware when this condition occurs.
Minimum supported client
|Windows 2000 Professional [desktop apps only]|
Minimum supported server
|Windows 2000 Server [desktop apps only]|
Build date: 11/16/2013