http://bugs.winehq.org/show_bug.cgi?id=35998
--- Comment #4 from Jarkko K jarkko_korpi@hotmail.com --- http://source.winehq.org/git/wine.git/blob/f820d9723b2725d0fa8cc2012ed50a686...
3592 /* Old games like StarCraft, C&C, Red Alert and others use P8 render targets. 3593 * Reading back the RGB output each lockrect (each frame as they lock the whole screen) 3594 * is slow. Further RGB->P8 conversion is not possible because palettes can have 3595 * duplicate entries. Store the color key in the unused alpha component to speed the 3596 * download up and to make conversion unneeded. */