The problem with winLockDontCare is that it doesn't just flip back and forth between two buffers, but rather allocates and then frees the second video buffer repeatedly. Since you have no guarantee of getting the same chunk of memory, you can't assume anything about the image data in the buffer. For example, parts of the memory could have been allocated as another chunk of memory that was used and then freed. So, even if the address of the buffer is the same as last time around, the actual content of the buffer may not be. This means you really can't use winLockDontCare unless you truly don't care. So much for updating the n-1 frame to get the n+1 frame.
The net result is that very few game developers do hardware page flipping. Instead, they tend to leave the screen pointing to the same chunk of memory, and update that memory using either the OS blitter or their own custom blitter. This works, but it limits the frame rate you can achieve. What is needed is a way to use WinScreenLock/Unlock in which the video buffer is not copied and not freed/allocated every other frame. -- Peter Epstein -- For information on using the Palm Developer Forums, or to unsubscribe, please see http://www.palmos.com/dev/support/forums/
