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superklye
11-01-04, 02:12 PM
I don't know exactly where I should put this thread, so this seemed like as good as any...

Are Pixel Shaders and Shader Models the same thing or not? I'm confused. PS 2.0 and SM 2.0 are or are not the same thing?

Pandora's Box
11-01-04, 02:18 PM
sm2.0 includes: pixel shader 2.0 and vertex shader 2.0

sm3.0 includes: pixel shader 3.0 and vertex shader 3.0

superklye
11-01-04, 02:22 PM
sm2.0 includes: pixel shader 2.0 and vertex shader 2.0

sm3.0 includes: pixel shader 3.0 and vertex shader 3.0
alright, thanks!

SH64
11-01-04, 03:25 PM
SM1.0(or 1.1) includes pixel shader 1.1-1.4 & vertex shaders 1.1-1.4 .

theultimo
11-02-04, 02:18 AM
SM1.0(or 1.1) includes pixel shader 1.1-1.4 & vertex shaders 1.1-1.4 .

Which 1.4 was designed for the Radeon 8500.

Chippy
11-02-04, 08:13 AM
I don't know exactly where I should put this thread, so this seemed like as good as any...

Are Pixel Shaders and Shader Models the same thing or not? I'm confused. PS 2.0 and SM 2.0 are or are not the same thing?

Not sure this completely clear from the answers you have got so far:

Cards don't run "Shader Models". They run Pixel Shaders and Vertex Shaders.

The term "Shader Model 3" is just means Shaders of type 3. And those type 3 shaders can be pixel shaders or vertex shaders.

Chip

msxyz
11-02-04, 09:56 AM
Shader model x.x means that both vertex and pixel shaders follow the x.x standard.

If I recall correctly, the Radeon 8500 had still vertex Shaders version 1.1 but pixel shaders 1.4.

I'm not sure if pixel shader rev 1.4 was introduced only to please ATi or as an intermediate step towards PS 2/3. PS 1.4 use 12 bit integer precision, has an extended range [-2,+2] and it's more flexible than PS 1.1. It's not a coincidence that Valve chose PS 1.4 as "fall back" path in their incoming HL2 title for those cards that cannot handle PS2.0 well. While there are still some visual differences, most of the effects are supported with little shortcuts.

SH64
11-02-04, 11:01 AM
Good info msxyz . i never had much info on the PS/VS1.4 .

btw IIRC PS1.4 is being used in some of the Unreal engine games like UT2003/04 & Thief 3 , but i'm not quite sure about that .

theultimo
11-02-04, 11:23 AM
Radeon 7200/7500 supported 1.0
Geforce 3 supported 1.1
Geforce 4 supported 1.3
Radeon 8500 supported 1.4
http://www.beyond3d.com/reviews/ati/radeon8500p2/

1.4 was a subset of DX8.1.

msxyz
11-02-04, 12:12 PM
Unreal Engine 2 uses Ps 1.4 to reduce the number of passes during terrain rendering and for "materials". Pixel Shaders 1.4 allow each texture to be read twice: PS 1.1 has a maximum of 4 texture lookups, PS 1.4 up to 12 from 6 different sources.

For a full listing of differences between PS 1.1 and 1.4 implementations, this is a good place to start: http://www.directx.com/shader/pixel/index.htm

Saw something similar on Microsoft developer network, although I don't remeber the link.

aAv7
11-02-04, 12:15 PM
I don't know exactly where I should put this thread, so this seemed like as good as any...

Are Pixel Shaders and Shader Models the same thing or not? I'm confused. PS 2.0 and SM 2.0 are or are not the same thing?

To break it down without all the technical mumbo-jumbo, yes...ps/sm is the same thing.

superklye
11-02-04, 12:27 PM
Thanks everyone, I think I understand it...and you don't have to coddle me...I'm not retarded when it comes to computers, and the technical stuff actually interests me. I just thought I would come here before searching online because it would easier to get a straight yes/no answer from you all.

rohit
11-03-04, 05:18 AM
Jus a guess, wen radeon will launch their r5xx series, they will suport it with SM 3.0b, jus like they they did with r3xx series, 2.0b, wich is not supported by dx9.0b, but its their own "extra "B" suypport" thingy.

i guess nv40 will support 3.0a or sumthin, n radeon will be a small step ahead with their own 3.0b

msxyz
11-03-04, 06:34 AM
Talking about PS 2.x differences, I've digged out this comparison table:

http://home.comcast.net/~langour/instructions.JPG

Fahim
11-03-04, 06:37 AM
SM1.0(or 1.1) includes pixel shader 1.1-1.4 & vertex shaders 1.1-1.4 .

I don't think there was any VS 1.4.

theultimo
11-03-04, 08:16 AM
I don't think there was any VS 1.4.

Yeah there was only 1.1, the PS was upped to 1.4 though.