When will MAME use Direct3D/OpenGL to emulate 3D games?
Probably not ever, at least in the sense this question is likely being asked. MAME now uses Direct3D (and SDLMAME uses OpenGL) to composite and scale the game graphics, artwork elements, and MAME UI displays, but the actual 3D rendering is always done in software in order to ensure consistent operation across different video cards and operating systems. Additionally, the bottleneck for many 3D games in MAME is actually their insanely fast RISC processor rather than the actual 3D rendering. This is the case in games such as Crusin USA, Killer Instinct (which has no 3D hardware anyway), and Gauntlet Legends.
