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Shader vs Fixed Function

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I'm thinking of using shaders for everything. I understand that some cards do this internally anyway. Does anyone know how the performance of shaders for replacing the fixed function pipeline is? Are there any resources online for shaders to replace common fixed function settings?

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Modern cards implement the FF pipeline by translating the calls into shader code.
Basically the performance of ASM shaders and FF calls should be identical.

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It is pretty safe to say that any function that was implemented in fixed function cards will run at least as fast on a DX8 or higher level card. I think the difference in implementation on the card itself is less of an issue than the clock speeds of the newer cards and the more highly parallel pipelines. The newer cards should be faster than the older fixed function pipelines.

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Bezben, if you've read the d3d10 preview article here, you'll know that the FFP will be done away with. So, yes, you're on the right track! [smile]

About your other question, take a look at the detailed specs for whichever API you're on. They will probably have equations explaining how it works, and you can incorporate that in your shaders.

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I have to say, with the FFP dissapearing in D3D10, I have say it's going to be annoying have to code all the basic stuff that the FFP provided.

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Annoying yes, but we will all get used to it :) Shaders provide such a [nearly] endless range of effect possibilties.

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It's not that bad, actually. You got used to all these cumbersome state switches and combiner values, while you could easily do all this a few lines of HLSL.
Look at the bright side - now you can change your rendering code on the fly without even having to restart your program [smile] (provided that your program allows for dynamic shader-reloading of course).

Cheers,
Pat.

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