edit: Tuncer explains it a little more in laymans speak!:
Mac gaming is about to get a huge boost in performance thanks to a new multi-threaded OpenGL. According to some people I've talked to, multi-threaded OpenGL games will see huge gains in performance. With multi-threaded OpenGL, the game, for example, can run off one core/CPU, while OpenGL can work on the second core/processor for its processing. So they work in concurrent fashion instead of co-habitating one CPU. The amount of benefit multi-threaded OpenGL games will have depends on how complex a scene in a game is. So, for example, in a very complex scene with lots of polygons, you'll see big gains in frame rates. One person told me they saw a very popular MMORPG DOUBLE in frame rates in one particular scene because of multi-threaded OpenGL. We're talking from 60 frames to 130 frames just in that one scene alone.
Now for the good news and some bad news. According to my sources, multi-threaded OpenGL is currently only available on the new Mac Pro systems Apple began shipping last week. But if all goes as planned, multi-threaded OpenGL will make its way into 10.4.8 (we think). If you have an Intel Mac (such as an Intel iMac or Mac Book Pro), then you will see the benefits of multi-threaded OpenGL. It is still unclear, however, whether Intel's GMA 950 graphics processor or old ATI/NVIDIA hardware found on older machines will get support for multi-threaded OpenGL.
But wait, there's a bit of a problem that we haven't talked about. There were some rumors last week that Apple might be holding multi-thread OpenGL for Leopard. Details are fuzzy on whether multi-thread OpenGL will make it into Mac OS X 10.4.8 Intel and/or Mac OS X 10.4.8 PowerPC.
This rumors hasn't sat well with some developers. In fact, one UK based developer has been holding off on releasing their products in anticipation of multi-thread OpenGL. If for some reason Apple decides to hold off on it until Leopard, that developer would have waited all these months for nothing.
One way or another, multi-thread OpenGL will make it to the Mac. It could be sooner rather than later but it's a distinct possibility that Apple will hold off on it until Leopard ships. In the meantime, though, the Mac Pro is the only Mac that currently has it.
One last thing to keep in mind...developers must patch to activate and take advantage of multi-threaded OpenGL.
http://arstechnica.com/staff/fatbits.ars/2006/8/17/5024For those who are interested, Apple announced that they are using the LLVM
optimizer and JIT within their Mac OS 10.5 'Leopard' OpenGL stack (which
was distributed in beta form to WWDC attendees).
LLVM is used in two different ways, at runtime:
1. Runtime code specialization within the fixed-function vertex-processing
pipeline. Basically, the OpenGL pipeline has many parameters (is fog
enabled? do vertices have texture info? etc) which rarely change:
executing the fully branchy code swamps the branch predictors and
performs poorly. To solve this, the code is precompiled to LLVM .bc
form, from which specializations of the code are made, optimized,
and JIT compiled as they are needed at runtime.
2. OpenGL vertex shaders are small programs written using a family of
programming langauges with highly domain-specific features (e.g. dot
product, texture lookup, etc). At runtime, the OpenGL stack translates
vertex programs into LLVM form, runs LLVM optimizer passes and then JIT
compiles the code.In non excessive geek language - in future optermised games we could be seeing
double the frame rate... sounds nice dosn't it!