NVidia announces Cg: "C" for Graphics

mr_sheel writes: "Thresh's FiringSquad has an article about Cg, a new language developed by NVidia in collaboration with Microsoft. 'Up until now,' Brandon Bell writes, 'game developers have had to use complex assembly language to create the lifelike graphics gamers experience in today's latest games.' Cg eases the process of bringing graphics to the screen and compiles for DirectX 8,9 and OpenGL 1.4. Many companies, including 3D Studio Max, Blizzard, and over 100 game developers, have already jumped onto the Cg bandwagon. Will this replace assembly graphics coding once and for all?"

Comments

Isn't this

[mcspock]

the same as this? http://slashdot.org/article.pl?sid=02/06/13/147213 &mode=nested&tid=126

Yes and No

[systemapex]

This is the news release that Slashdot actually gets paid for by Nvidia.

Hey Timothy!

[cp4]

Hey Timothy.... go to your preference page and UNBLOCK all CmdrTaco stories.... this way you can see what he posted and not post it yourself.
I know some of his stories suck but it's for the good of all of us.

You can keep Katz stuff blocked.

Re:No news good news.

[JPriest]

The girl next door?

User Bio:
Active Open Source bi-geek girl who loves boys with ear-rings and enjoys reading Playboy in the train. I play bass in an all girls band and work in the porn movie industry as an amateur actress to pay for my scholarship. Drop me a line sometime...

Next door to whom exactly?

See what some game developers think

[magic]

At flipcode.com

-m

Why it won't work (link)

[Space Coyote]

There's an interesting editorial at The Register pointing out some of the flaws in Cg, and speculating about NVidia's intention for future development of the language as it relates to their core graphics hardware busines.

From the article:

• No break, continue, goto, switch, case, default. These are useful features that can be used without penalty on other vector processors.
• No pointers. This is Cg's most serious omission. Pointers are necessary for storing scene graphs, so this will quickly become a serious omission for vector processors that can store and process the entire scene or even sections of it.
• No integers. This may be appropriate to NVIDIA, but is not a universal design decision.
• Arrays use float indices. This is an odd design decision, relevant to DirectX 8 and Nvidia only.

It may be possible that NVidia is holding back support for such rudimentary language features until such time as they are supported in their own hardware. I don't think this is a formula for a widely-adopted language at all, and smells a little of 3dfx's efforts with Glide.

Re:Why it won't work (link)

[donglekey]

Whomever wrote that article may understand 3D, but doesn't understand where shaders fit in and the history and experience already here. Pixel and Vertex shaders have been around since the inception of commercial 3D in the form of Renderman surface and displacement shaders. They are small and very modular programs which don't need access to a large amount of information at one time. Thus because of the implied modularity, and the isolation of the calculations relative to the rest of the scene there is no need for OO (I know you didn't mention it, but someone in the FIRST story about this did, and its a good question), and no real need for pointers.

Furthermore because of the very analog nature of what is being descibed, control statements and desicion shortcuts aren't a very big deal. Of course there are if else statements, but they are not used as much as simple and very general algorithms. Hard desicions lead to aliasing, because they rule out a gradual change. Also because of the analog nature of what is being reproduced integers are used very rarely, almost exclusivly for loop counters.

Using float indices for arrays is a kick ass design descision. It allows for smooth and elegant interpolation between discreet values, and I can't stress what a cool idea that is.

In short, the register is wrong, and this IS a formula for a widespread language, because it is copying another very mature widespread language, the Renderman shading language. The only thing I am worried about is that it will be geared towards only Nvidia products, thus competing with OpenGL 2.0 (whenever the vapor settles).

Keep in mind that I am not trying to argue you, but I am trying to argue the register's stance. The designers of Nvidia are very aware of the vast history of Renderman I am sure, and this language looks just fine.

For anyone who wants to get into writing shaders, the book 'Advanced Renderman: Creating CGI for motion pictures' by Anthony Apodaca and Larry Gritz is your bible. it covers everything you need to know and more, and I highly recommend it.

I kan read artical

[Enonu]

Since Cg is designed specifically for vertex and pixel shader programs, DirectX versions 8 and 9 are supported as well as OpenGL 1.4. The compiler itself is cross platform; in particular programs written for Windows, Linux, Macintosh, and Xbox are supported. And if all that isn't enough, the compiler can create code for all GPUs that support DirectX 8 (or above) and/or OpenGL 1.4, making it very universal. In keeping with Linux tradition, NVIDIA has open-sourced certain components of the compiler, allowing content developers to add their own customizations as well.

cgshaders.org and Linux Toolkit

[Screaming Lunatic]

The official community site is at cgshaders.org. There's a Linux Toolkit out now. There's a interview with CEO David Kirk. Along with articles, a shader repository, and forums for help.

Re:What Are You Talking About?

[liquidsin]

Since Cg is designed specifically for vertex and pixel shader programs, DirectX versions 8 and 9 are supported as well as OpenGL 1.4. The compiler itself is cross platform; in particular programs written for Windows, Linux, Macintosh, and Xbox are supported. And if all that isn't enough, the compiler can create code for all GPUs that support DirectX 8 (or above) and/or OpenGL 1.4, making it very universal. In keeping with Linux tradition, NVIDIA has open-sourced certain components of the compiler, allowing content developers to add their own customizations as well.

Do you even read articles? How did you get modded insightful? Do moderators read articles?

Wow!

[be-fan]

I'm impressed. This is the second time this has been posted on /., and people are STILL clueless about what Cg is! Incredible!

Cluestick: Cg is not a language like C/C++. It is not an API like OpenGL/DirectX. Instead, it is a simple, high-level replacement for the assembly language traditionally used to program pixel and vertex shader units on graphics cards. These programs are typically a few dozen instructions long and basically map a small set of inputs to a small set of outputs. So you could write a program to rotate a vertex around a point in Cg, but not something like Quake...

OpenGL 2.0 Shader Language

[RoninM]

Cg looked awfully familiar to me (and not just because we had this article, before). You might want to compare it to the OpenGL 2.0 Shader Language defined here (PDF) and implemented here.

All of this leaves me a little bit confused. I'm not sure why we need two (or, perhaps, more) C-based shader languages, at least one of which (Cg) is hardware-specific, but API neutral.

Re:What Are You Talking About?

[fferreres]

Do you even read articles? How did you get modded insightful? Do moderators read articles?

Yes, I think they do read them. There's nothing in the article that contradicts what he says. Actually, Nvidia IS IN BED with Microsoft. 3Dfx was not and got killed. 3DLabs was not and suffered.

If it werent't for Id, i'd say OpenGL will be dead right now and you would not be able to play any 3D games but loading Windows.

Now, all this can sound unsound, but if you really followed what happened in the 3D world since 1995 you will notice it's not a crazy idea.

Microsoft needs the games to run under Windows and XBox, and to NOT run on any other plataform. This is as true as the sky is blue. So the original poster does have a valid point with I'd mod as Insightfull any day.

BSOD refresh rates

[theMightyE]

With Microsoft involved we will still get the Blue Screen of Death, only now it'll be anti-aliased, vertex shaded, and happen at 400+ fps.