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NVIDIA's Pixel & Vertex Shading Language
Barkhausen Criterion writes "NVIDIA have announced a high-level Pixel and Vertex Shading language developed in conjunction with Microsoft. According to this initial look, the "Cg Compiler" compiles high level Pixel and Vertex Shader language into low-level DirectX and OpenGL code. While the press releases are going amok, CG Channel (Computer Graphics Channel) has the most comprehensive look at the technology. The article writes, "Putting on my speculative hat, the motivation is to drive hardware sales by increasing the prevalence of Pixel and Vertex Shader-enabled applications and gaming titles. This would be accomplished by creating a forward-compatible tool for developers to fully utilize the advanced features of current GPUs, and future GPUs/VPUs." "
You've got to wonder, is this yet another load of Nvidia corporate hype (a la "HW TnL will revolutionise gaming"), or is this useful technology? I wouldn't trust any of the current articles on answering that, judging by the previous Nvidia hypes, it takes a few months till anyone really knows if this is good or bad.
Switch back to Slashdot's D1 system.
There are some issues that I think nobody seems to be addressing, as in:
* Realistic fog/smoke -- not that 2-D fog which looks like a giant translucent grey pancake. Microsoft comes closer with Flight Sim 2002, but it's not quite there yet.
* Fire/flame -- again, nobody has created more realistic acceleration for this kind of effect. It's very important for many games.
Furthermore I would like to see fractal acceleration techniques for organic-looking trees, shrubs, and other scenery. Right now they look like something from a Lego box. In fact, fractals could probably help with fire/smoke effects as well, to add thicker & thinner areas which take on a "semi-random", but not an obvious pattern, effect.
Perhaps I'm just too picky...
-- We live in a world where lemonade is artificial and soap has real lemon.
I am being completely serious. A modern computer is an asymmetric dual-processor system. GPUs are already at least as complex as CPUs, and when the shader language becomes Turing-complete (when jumps, conditionals, and some other things are added) the GPU will be a CPU and it will be pointless to ship a computer with 2 unequal general-purpose CPUs.
IMHO, OpenGL 2.0 is more portable, less NVidia-specific and backed by more manufacturers. Cg is a ripoff of OpenGL 2.0's design, in a cheap attempt to turn it into a NVidia/Microsoft controlled standard.
Remember, NVidia may be good now, but they got where they were by being competitive and overturning old-guard 3D guys (like 3DFX who were themselves trying to lock the industry in to APIs they controlled).
Competition=good.
Single-vendor-controlled APIs=bad.
OpenGL2.0=good.
Now, Ilike my NVidia hardware as much as the next guy, but I fear lock-in. Seems like most of us have already experienced the downsides of lock-in.
Yes, NVidia is talking up the buzzwords "portable" and "vendor-neutral" but if that's what they were after, the wouldn't have created Cg at all, they would have gone with the already-available open standard, OpenGL2.0. This is embrace, extend and extinguish.
-- There is no truth. There is only Perception. To Percieve is to Exist.
Maybe I'm a bit paranoid (I probably fit right in on /.) but when I read news subheadlines like "Nvidia, the dominant PC graphics chip maker, has teamed up with Microsoft and developed a new cross-platform graphic language called Cg that it hopes becomes an industry standard" I don't really feel all warm & fuzzy inside. CG Channel states "NVIDIA's compiler toolkit would be more optimized for their own hardware owing to greater understanding of their own technology. ATI would have the option of writing their own backend compiler to support their hardware more optimally, but the exisiting NVIDIA toolkit should generate working code on ATI's part. [...] NVIDIA are hoping that Cg will be the industry's defacto standard simply due to its time on the market [...]" If NVIDIA can't be reasonably criticized for supporting their own chipset more with optimized code (and leaving it open to others with competing chipsets), can co-developer Microsoft be criticized for favouring their own software in this? Couldn't MS solutions (DirectX, XBox-specific tools, etc) be favoured under Cg merely by them investing more in Cg development and (as one of the two developers controlling the standard) updating compilers and shader functions for their software sooner or more completely than for others? If this was the case, Cg could just end up being another "embrace, extend, etc" scenario, this time in the graphics market to push MS & Nvidia techologies.
Nvidia has been fair to good in their cross-platform support so far, but of course MS has not been. To the relief of many CG Channel reports that "Interestingly, key components of NVIDIA's Cg compiler will be open-sourced and will work on Linux, Mac OS X and Xbox platforms. [...] Compiled code for Direct3D will be cross-platform (well, as cross platform as Microsoft might expect). OpenGL code should work much the same as long as the OpenGL extensions are supported on the target. NVIDIA says it will provide compiler binaries for all of the major platforms." The real proof will be in how Nvidia supports Cg on other platforms and OpenGL over the long term. Will these binaries be released at the same time and with the same feature sets? And will this continue to be the case or will full cross-platform support only exist in the beginning until Cg becomes a de facto standard?
I'm skeptical at this point, since we all know there's a world of difference between being merely compatible and being optimized. There's some evidence so far of how Cg is being implemented. For instance, it looks like there isn't an OpenGL fragment program profile for the Cg toolkit while there is one for Direct3D8. Nvidia says that the reason Cg has for no OpenGL ARB vertex_program extension while there are both dx8ps and dx8vs profiles is that OpenGL is dragging it's heels with the standard, perhaps valid but nonetheless the result is Cg is better implemented under DX8 than the OGL side. While it's theoretically possible to program Cg textureShaders and regcombiners in OpenGL, it's not currently supported. Much of the feature set in Cg looks like that announced so far for OpenGL2 - could nVidia just be trying to repeat OpenGL2 functions using their own identical and properitary Cg extentions instead? Finally, Nvidia announced support for Windows, MacOSX and Linux; the first and last platforms should have native Cg compilers (Linux soon apparently) but what about MacOSX?