[AD] Latest QNX additions

["a.mottola@xxxxxxxxxx"<a.mottola@xxxxxxxxxx>]

Ok, I´ve just put on CVS a new version of the QNX port. This one finally adds color conversion to the windowed gfx driver, thanks to Eric´s efforts in bringing the Win32 conversion API to be common for all ports. I´ve also added display switching support, but this was only tested for the windowed driver and supports only the background mode...

I still have difficulties with threaded events handling: George´s suggested method about using usleep() inside the events thread didn´t help, and my try of putting it inside the timer interrupt handler (which is part of the main thread) failed too.
IMO it is a matter of scheduling priority: now, how to change it?
I don´t know how to do that with pthreads.

pthreads should have a pthread_yield() function (as reported by some online tutorials I read), but this seems to be missing on the QNX implementation... This function could be a solution, as calling it on the timer interrupt could help giving more CPU time to the events thread. Too bad I can´t use it!

Well, the QNX port works nicely for now except these things:
- events handler synchronization is bad
- untested display switching in fullscreen mode
- window close handler doesn´t support system warning message before forcing shutdown

For the future I plan on adding:
- video bitmaps and hardware acceleration
- video overlay windowed gfx driver

--
Angelo