Pixel Shader v1.1 vs v1.3 - Do Any Cards Only Support v1.1?

Pit_Viper

Newcomer
Greetings all,

Support for Pixel Shader 1.1 seems to be a trend with software that supports DirectX 8.1 Pixel Shaders. I was curious as to why Pixel Shader 1.3 isn't used as the base standard for DirectX 8.1 cards - are there some cards that support Pixel Shader 1.1, yet don't support Pixel Shader 1.3? Off-hand, I cannot think of any such cards...

Thanks in advance...
 
Re: Pixel Shader v1.1 vs v1.3 - Do Any Cards Only Support v1

Pit_Viper said:
1.3 isn't used as the base standard for DirectX 8.1
Plus, 1.3 (and 1.2 for that matter) only give you several additional "hacks" over ps1.1 (dp4, modify depth, etc.). In most cases, either 1.1 is sufficient (so there's no need to use higher model), or 1.1 AND 1.2 AND 1.3 aren't sufficient. Pixel shader 1.4 is a different story (it's a whole new model).
 
GeForce 3 does not support PS 1.3.
Actually GF3 supports the "Z modify" instruction in PS 1.3, but it lacks some instructions in PS 1.2, and PS 1.3 requires PS 1.2. So GF3 is not able to support PS 1.3.

By the way, I believe that some chips from SiS (Xabre ???) also support PS 1.1 only.
 
Pit_Viper said:
arjan de lumens said:
GeForce3 cards are limited to PS1.1.

I have already searched for an answer regarding the Pixel Shader support of the Geforce 3, and I always come up with conflicting information regarding this topic.

Yeah, but GF3 does not support Pixel Shader 1.3. The other question is that whether or not XGPU supports Pixel Shader 1.3.
 
embargiel said:
Yeah, but GF3 does not support Pixel Shader 1.3. The other question is that whether or not XGPU supports Pixel Shader 1.3.

The XGPU does not support Pixel Shader 1.3 with regards to the exact specifications, from my understanding. It supports a Pixel Shader 1.1 variant (with different mnemonics, 9 instructions maximum) that is more or less functionally equivalent to Pixel Shader 1.3. I don't think any documentation regarding the shader mnemonics is readily available to the general public. (Somebody correct me if I'm wrong with respect to any of the aforementioned points.)
 
Well, then I don't know any chips other than GF3 series which support PS 1.1 only... :p
 
No you are correct, i meant that that to most people it sound like 1.3-1.4 is very near technical by the numbers but the difference is much bigger hence my 1.8 number. ;)
 
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