Yep, it's simply a GL_ADD and GL_MODULATE setup. Very basic stuff, it can be done in standard OpenGL with the texture_env_add extension. But most people don't use this (rather primitive) system anymore.

That's why texture_env_combine was made part of OpenGL in version 1.3, although pretty much every 3D card supported the texture_env_combine extension long before that. The principle is exactly the same as the D3D texture stages.

Choose your equation per texture unit, attribute RGB and alpha arguments. Vendor specific extensions (texture_env_combine4) went even further, increasing the choice of equations. Actually, those combine equations reflected exactly the maximum combine capabilities of the hardware at the time they came out (the TNT2 already supported texture_env_combine4, the GeForce family added regcoms, and ATI added texture_env_route). Note that none of those are pixelshaders, they are just combiner functions. As I said, extremely precise and pretty powerful (considering the hardware they were developed for).

So please, if you try to compare D3D with OpenGL in the future (although one should avoid this very volatile comparison...), then at least get informed before drawing conclusions, and calling a feature "sickeningly bad", if you don't even understand how it works.

(I just realised, funny I'm telling this to the person who wrote the D3D vs. OpenGL article... )


[edited by - Yann L on March 6, 2003 7:33:07 PM]

Hmmm Im glad microsoft has left. I don''t hate microsoft in any way and I use their OS, but they do have a problem with wiping out any form of competition. Actualy I don''t see how they lose any money by people using OpenGL, sure it means that people with different OSes can play the games too, but no one developes a game that doesnt run on Windows. Except zealots who put down with M$ and windows in the game credits. Also we as people have said microsoft hasn''t really supported openGL at all since 1.1 and its still going strong, and we are seeing things like Cg that still fully support it and wipe out the extension work. The only way I can see MS wiping out OpenGL is if they decide to make DX multiplatform then if they get everyone to switch to it then when its to late to switch to anything else MS switches back to just supporting windows. If they tried that I think I would start a MS hate site:D

I don''t think OpenGL will go anywhere, and even though im beginning to learn DX as well, I will always use openGL to program, and as soon as I find a good multiplatform input API then I won''t use DX at all. Also another thing to remember is that consoles(at least the PS2) use openGL. MS will never be able to crush it no matter how hard they try. It would be great if we all a sudden saw the ARB stating they are releasing 2.0 in the next month.

I don''t mean to get off topic but I just have a question that for some reason Ive never asked before. Will the majority of you use Cg or will you just drop it all together and just program using GL 2.0 without Cg?

I have tried SDL I don''t like it very much. I know the MS''s idea is to make it so everything only works on windows, but by doing this they are causing more and more people to not like them. When I say people I mean developers, so in the long run having such an atitude may cost them money. I myself know many people who stopped using DX and hate microsoft due to their "world domination" antics. Also I was talking about the PS2 implimentation of OpenGL and I actualy think consoles will move towards using openGL. Since the xBox basicly uses DX which makes it easy for PC developers to develope for, other consoles will want to make it easier for developers as well. Even John Carmack said one of the downfalls of the PS2 is that its more difficult to develope for, so if sony is smart they will adopt something like OpenGL to make it easier to some extent at least.

A simple yes would have sufficed

Join the World Wide Revolution:

Intresting yet outdated article:

http://www.vcnet.com/bms/features/3d.html

quote:In the course of this campaign for control of a new market, Microsoft consistently:

Acquired or adapted technology from outside organizations, rather than innovating on its own.
Used its marketing presence to spread demonstrably false information.
Refused to respond to the direct requests of its independent software development partners.
Leveraged the market domination of Windows to promote its own products over superior products available from other sources.
Used its position as supplier of essential software to curb dissent.
Acted to extend or protect its own control over the market, even at the expense of its business partners and of consumers in general.

We can extrapolate this and other Microsoft behaviour that they will probably do something that hurts developers or consumers somewhere along the line and their quitting the ARB has something to do with it.

With any luck, however, it will not be as awful as distroying the ARB or OpenGL. No doubt they will try, or at very minimum, consider it.

Do not meddle in the affairs of moderators, for they are subtle and quick to anger.ANDREW RUSSELL STUDIOS
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