- Direct3D (all: Microsoft)
- OpenGL (all: open standard, ARB group)
- Glide (3Dfx only)
- MeTaL (S3 only)
The last two performed very well, but only on the corresponding hardware. Unreal Tournament & Deus Ex where the best games to test all these render modes in action.
Time passed, and Glide & Metal silently died, leaving GL competing with D3D, having only a single guard: Id Software. I can only guess what would happened to GL at that time if there was no John Carmack (Id lead programmer)... S3 technology was bought my MS that spread S3TC wisdom all over the word.
OpenGL standard developed very slowly, but easy extension mechanism allowed programmers to use all the new features Direct3D contained, and even more. Microsoft performed a massive information attack on GL (see FUD) leaving only cross-platform games alive.
Now there is XNA, Win7 with its DX11 and hordes of MS fans lurking around with their XBox'es. Other camp primarily consists of Unix/Linux systems, Mac OSX and a bunch of smart embedded devices including PS3. As far as I see, the time of revenge has finally come!
OpenGL ES (at least 2.0) has a very successful design: simple, portable, effective. It was developed by Khronos group that is now pushing forward OpenGL-3 standard. Microsoft was not able to spread it's massive OS on mobile devices, and now we have numerous game-dev companies working on iPhone & PS3 games using OpenGL ES only. Moreover, Linux & Unix community grows: they might not be willing to pay for games, but they are developing exclusively on GL. At the same time, we have Mac OSX users that easily afford themselves buying games, forcing major titles being released for this OS (take Dragon Age for example).
The conclusion is: there is no point to develop your engine primarily for Direct3D unless you want to run on XBox. OpenGL successfully covers all other platforms (there is only a little difference between ES and normal GL nowadays), has a clear extensible design and an open standard. Congratilation, my friends, our victory is close! And the world will be a little better place to live soon :)
P.S. Some people say you don't have to choose and support both API anyway. That's true, but don't forget about the future: your choice may shift the balance in this fight giving an initiative to the hands we can't trust.