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mnemonicj
03-12-2002, 01:57 AM
Documentation (nVidia SDK 5.1) says that GF3 supports Bezier patches in hardware via GL_NV_evaluators.

To compare performance between hardware support I tested two cards on two computers :
1. Duron600, 384MB SDRAM, GF3
2. AthlonXP 1600+, 256MB DDRAM, GF2 Ti

I've got, on
1. 7.71 fps
2. 49 fps

Program used for benchmarking is patch_ase from older nVidia SDK.

I investigated further, and used D3DDevice->GetDeviceCaps() and it says that GF3 that it doesn't supports RTPatches (Bezier Patches).

Is it weird, or is it just me???

[This message has been edited by mnemonicj (edited 03-12-2002).]

zeckensack
03-12-2002, 04:25 AM
For some reason, HW acceleration for that has been dropped in the more recent driver sets.

Diapolo
03-12-2002, 04:57 AM
But only for D3D, because it conflicted with ATIs TruForm (read that somehwere).
The support for GL_NV_evaluators should be HW accelerated on NV20 and higher.

Diapolo

Humus
03-12-2002, 08:47 AM
Originally posted by Diapolo:
But only for D3D, because it conflicted with ATIs TruForm (read that somehwere).


Not sure about that. I've heard that it was dropped in D3D because of lack of interest from developers.

mnemonicj
03-13-2002, 12:46 AM
Originally posted by Diapolo:
But only for D3D, because it conflicted with ATIs TruForm (read that somehwere).
Diapolo

Can you point me to link or something else, where can I found more information about this topic?

I don't understand the reason for dropping out hardware support (in D3D) for Bezier patches, when ATI has N-Pathces support...
Please, inform me...

mnemonicj
03-13-2002, 12:51 AM
Originally posted by zeckensack:
For some reason, HW acceleration for that has been dropped in the more recent driver sets.

It' turns out that patch rendering is hardware assisted, but tesslleation is done on CPU (crack check...) so it can be bottleneck...