Naure test......

[Hellbinder]

Something that has always struck me as a little odd....

The 3dmark nature test, is supposed to be a Pixel shader test. Yet it clearly has an EXTREME number of pollies.. It seems to me like its much more of a vertex text than a Pixel Shader test... Or a complete complex scene test... similar to codecreatures...

For a True test of the Pixel shaders, wouldnt you want a much more simple scene, with greater and varied use of lighting, shadows, and Surface effects?

 

[Dave Baumann]

AFIAK the nature test has alyways been billed as a Vertex and Pixel Shader test, not just one.

 

[Gunhead]

And perhaps it doesn't have quite that very extreme poly count after all, due to clever use of pixel shaders, texture alpha etc. That's what I've read about it, anyway. (Don't remember where, but I remember it seemed to be a person who understood the stuff pretty well. Better than me, anyway.)

 

[quattro]

copied form 3d mark help file:

Technical details:

* The leaf and grass movement is done using a vertex shader.
* The fisherman animation uses morphing done with a vertex shader.
* The butterfly flight and wing movements is done with a vertex shader.
* The lake surface uses a pixel shader for per-pixel reflection and cube mapping
(it uses 4 texture render states, which corresponds to 4 texture layers)
* The small river has two separate water surfaces, both using two texture layers (color map and light map).
* The landscape, the house and the bridge has two texture layers (color map and light map).
* The leaves, grass and the fisherman have a single texture layer.

High detail statistics:

* Rendered triangles per frame (min/avg/max): 55601/81722.5/180938
* Rendered textures per frame with 16 bit textures (min/avg/max): 14.9/17.4/20.7 MB
* Rendered textures per frame with 32 bit textures (min/avg/max): 28.4/33.4/40.0 MB
* Rendered textures per frame with texture compression (min/avg/max): 10.4/12.0/14.6 MB
* Rendered textures per frame with DXT1 compressed textures and 32 bit transparent textures (min/avg/max): 13.0/15.0/17.8 MB

 

[Gunhead]

Thanks, quattro.

So... the foliage is vertex shader stuff. Not clever alpha. My bad. Anyway. The lake is heavier on the pixel harware. The rest appears to be somewhat non-demanding dual or single texturing. What was the question again? I guess DB nailed it in the very follow-up reply. Then again, I'd myself never believe such a short answer

 

[OpenGL guy]

So... the foliage is vertex shader stuff. Not clever alpha.

Pretty sure the foliage is alpha texture but the vertices of the polygons are manipulated with vertex shaders. If you watch carefully, you can see "chunks" of leaves that move together... those are the polygons with the alpha texture (leaves) on them.

 

[3dcgi]

OpenGL guy is correct. They still do a lot of alpha blending with rectangular polygons. The leaves are not detailed geometry. There's just a lot of them.

 

[up]

What i don't understand is that nature shows up in demo-mode but not in benchmarkmode (e.g. GeforceGTS)

 

[OpenGL guy]

What i don't understand is that nature shows up in demo-mode but not in benchmarkmode (e.g. GeforceGTS)

Maybe it requires HW vertex/pixel shaders to get a score? Dunno. What do the docs say?

P.S. Of course, doing SW pixel shader is unlikely, but possibly the effects used in the scene can be simulated with fixed-function pixel shader ops.

 

[SvP]

What i don't understand is that nature shows up in demo-mode but not in benchmarkmode

That's because there is no water in demo mode?

 

[Nick[FM]]

What i don't understand is that nature shows up in demo-mode but not in benchmarkmode (e.g. GeforceGTS)

In the demo we don't use any Pixel Shaders, which makes it possible to run it on any hardware. The Nature test and the demo nature scene are not the same at all!

Hope this helps..

 

[Neeyik]

Just to expand on what Worm has said, pixel shaders are only used to create the lake surface. If you look carefully during the "Nature" part of the demo you'll see that that the lake is never shown.

Also, if you read the Making of 3DMark2001 it should make even more sense as to what is going on:

http://gamershq.madonion.com/articles/makingof3dmark2001/?page=4

 

[up]

Thanx, but now i've been evan more impressed by your engine to get such nice trees and leaves with SW T&L
btw, there is water in the demo-nature!

 

[Neeyik]

The water in the demo is not done with pixel shaders though, "just" a couple of texture layers for each surface. In the Nature game test, pixel shaders are used to modify the surface of the lake only (the difference in effects is quite noticable).