Quote Originally Posted by User137
The best transparent color is Black. I've seen other colors having problems, when changing color manually. I think proper color would come when you get pixel from DXSurfaceCanvas of picture (not from DXSurface.Pixels).

These colors may not be in form $FFFFFF which normally would be white.
In my experience the best color for transparency is MAGENTA as it is easily replaced by other colors. Black, on the other hand, is used a lot, to border the sprites, for example. I've also encountered problems using black for transparency on WinME, dunno why, though, as the game worked fine on other OSs.

I select the transparent color by checking the color of the pixel[1,1] and it works fine.