The ICM_DRAW_START message notifies a rendering driver to start its internal clock for the timing of drawing frames. You can send this message explicitly or by using the ICDrawStart macro.
ICM_DRAW_START
wParam = 0;
lParam = 0;
This message does not return a value.
This message is used by hardware that performs its own asynchronous decompression, timing, and drawing.
When the driver receives this message, it should start rendering data at the rate specified with the ICM_DRAW_BEGIN message.
The ICM_DRAW_START and ICM_DRAW_STOP messages do not nest. If your driver receives ICM_DRAW_START before rendering is stopped with ICM_DRAW_STOP, it should restart rendering with new parameters.
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Unsupported.
Header: Declared in vfw.h.
Video Compression Manager Overview, Video Compression Messages, ICDrawStart, ICM_DRAW_BEGIN, ICM_DRAW_STOP