Valve Sponsors Work To Greatly Speed-Up Linux OpenGL Game Load Times
An anonymous reader writes "Valve Software has sponsored some interesting improvements developed by LunarG for the Mesa OpenGL library on Linux for deferred and threaded GLSL shader compilation. What these changes mean for users of the open-source Linux graphics drivers when running their favorite games is that OpenGL games now load a lot faster. As an example, the time from starting Dota 2 until the time actually being within the game is reduced by about 20 seconds on an Intel system. While Direct3D has offered similar functionality for a while, OpenGL has not, which has given it a bad reputation with regard to game load times until all shaders are compiled and cached — fortunately it's now addressed for OpenGL if using the Mesa Linux graphics drivers on a supported game."
An IR doesn't buy you much. The time taken for clang to compile OpenCL C to SPIR is about 10% of the time required for LLVM to optimise and codegen the resulting SPIR into native code. The driving force behind SPIR comes from developers who don't want their shader source code embedded in their binary source.
I am TheRaven on Soylent News
Even on windows, OpenGL is not that much slower, on the order of 10% for 'normal' 3D game code. With a modern video card that difference almost doesnt matter.