It's been a while. Things were a bit hectic. Nevertheless I am back.

These days I am working on a rather interesting project involving DirectDraw on Windows Mobile 6. Without going into the project details, I wanted to share some experiences. So far, a number of time I would run into an issue, and of course not it would not be explained/documented/covered anywhere where the Google search takes you. It struck me that I must be not the first one to hit these issues, and if I list them here, chances are that Google search will be more productive for the next poor sod to plow through underdocumented (to put it mildly), convoluted (again, to put it mildly) and unforgiving API such as DirectDraw. I am going to have multiple posts with keywords facilitating search. If a month from now you will find out that I produced all of one post (this one seems to be on track so far. Chances for it not making it are slim), don't judge me too hard. I am away from home for the 3rd week in a row, having missed Christmas, but should be back for the New Year. Ok, here goes.

Call to IDirectDrawSurface::Blt returns DDERR_SURFACEBUSY

The documentation says to check for other threads accessing your surface at the same time. The group search suggests to search for mismatching Lock/Unlock calls. The actual cause turned to be a missed call to IDirectDrawSurface::ReleaseDC (after a successfull call to IDirectDrawSurface::GetDC). If you think about it, internally these calls must be using Lock/Unlock, so cudos to Group search and boo to MSDN documentation