The battle between OpenGL & DirectX is a holy way in the gaming community, usually with DirectX winning because it is supported by most games.  When working in cross-platform environments, however, OpenGL is the clear winner.  Wolfire games, creator of several games for multiple platforms, has a new blog post detailing their choice of OpenGL over DirectX, and it gets beyond the “Well, DirectX doesn’t work on Mac or Linux” and gets into some good technical reasons why OpenGL still hangs around.

It’s common knowledge that OpenGL has faster draw calls than DirectX (see NVIDIA presentations like this one if you don’t want to take my word for it), and it has first access to new GPU features via vendor extensions. OpenGL gives you direct access to all new graphics features on all platforms, while DirectX only provides occasional snapshots of them on their newest versions of Windows. The tesselation technology that Microsoft is heavily promoting for DirectX 11 has been an OpenGL extension for three years. It has even been possible for years before that, using fast instancing and vertex-texture-fetch. I don’t know what new technologies will be exposed in the next couple years, I know they will be available first in OpenGL.

The conclusion of his article is particularly powerful, stating how DirectX only really exists to prevent games from leaving Windows Platforms.

via Why you should use OpenGL and not DirectX – Wolfire Games Blog.