View Full Version : Radeon's priority buffers

03-09-2001, 05:26 AM

Could anybody tell how to use subj from OpenGL? Is it possible at all? The example on Ati site uses D3D http://www.opengl.org/discussion_boards/ubb/frown.gif

[This message has been edited by h2 (edited 03-09-2001).]

03-09-2001, 10:25 PM
Apparently, there's actually no way to use those in OpenGL http://www.opengl.org/discussion_boards/ubb/frown.gif
As for the pixel shaders and EMBM ...
ATI is kinda WEAK in it's OpenGL support !

03-10-2001, 02:15 PM
RADEON doesn't support pixel shaders. Three-texture multitexture is available via a combination of extensions.

The ATI_envmap_bumpmap extension exposes EMBM and is already in the drivers. If you're a registered developer you should already have access to this.

03-10-2001, 04:55 PM
How come then that the "MFC pixel shader" DX8 SDK sample is running with HAL and is running much faster then with the REF rasterizer? Doesn't that mean that it is rendering the pixels shading stuff in hardware? Or have I misunderstood something?

03-10-2001, 05:49 PM
What driver version do you use Humus? I have the lastest beta they released on their site and MFC pixel shader uses the reference rasterizer.

JasonM [ATI]
03-10-2001, 09:14 PM
I don't think you're running MFC Pixel Shader on the HAL on RADEON™. Can you look at it in a debugger and see where it's looking for the pixel shader version supported? RADEON™ should be reporting 0.0.


[This message has been edited by JasonM [ATI] (edited 03-10-2001).]

03-11-2001, 02:39 AM
Originally posted by JasonM:

The ATI_envmap_bumpmap extension exposes EMBM and is already in the drivers. If you're a registered developer you should already have access to this.


Can anyone be a registered developer? Its just that when I looked they were asking for contact details for a Marketing representative. I'm just a late night OpenGL hacker who wants to keep up with the DX8 boys.

03-11-2001, 08:25 AM
Yeah. I would like to have access to that driver.

I tried to find it on the web, just in case it would have been leaked http://www.opengl.org/discussion_boards/ubb/smile.gif, but I could not find it.

03-11-2001, 04:35 PM
Originally posted by JasonM [ATI]:
[B]I don't think you're running MFC Pixel Shader on the HAL on RADEON™. Can you look at it in a debugger and see where it's looking for the pixel shader version supported? RADEON™ should be reporting 0.0.


It reports 1.0

Look, there's a registry key called "PixelShaderVersion". If I set this to "10" this sample runs supposedly with hardware support for PixelShaders version 1.0, if I set it too "0" or remove the key it'll only run with REF renderer.

I have a screenshot here with it running with HAL if you want more proof:


[This message has been edited by Humus (edited 03-11-2001).]

03-11-2001, 05:48 PM
Why isn't that in your tweaker Humus?

03-11-2001, 05:59 PM
It is.
Look in advanced settings.

03-11-2001, 07:51 PM
It's working allright, but if you try and run the NVEffectBrowser, it just crashes if you use hardware device.

So maybe they implemented a chunk of it, or dx8 can actually use "normal" texture and coloring if the shader is simple??

JasonM [ATI]
03-12-2001, 07:33 AM
Guilty as charged. We implemented the subset of pixel shaders that translate into legal multitexture combinations on RADEON™ You didn't say you were tweaking the registry http://www.opengl.org/discussion_boards/ubb/wink.gif

Unless you hack the registry, we will report 0.0 pixel shaders. The whole "0.5 pixel shader" thing turned into a real hairball, and you can get a lot of the RADEON™ functionality through DX8's enhancements to SetTextureStageState (stuff like LERP, MAD, TEMP and ARG0), so we decided to focus on other areas.


P.S. This isn't exactly an OpenGL topic so, if you have related questions that don't belong here, feel free to ping me directly at JasonM@ati.com. And ping devrel@ati.com to enquire about becoming a registered developer.

[This message has been edited by JasonM [ATI] (edited 03-12-2001).]

03-13-2001, 03:14 AM
I'm really happy an ATI guy comes on this forum !
I'm registered dev since a few months now and ... i got almost no info except some beta drivers which were already outdated by some illegal (leaked?) distributions.
No OpenGL docs (ATI_VERTEX_STREAMS ???) !
So some questions :
- What are those VERTEX_STREAMS exactly (it is like the DX vertex streams ?)
- Does ATI plan to add more support to OpenGL for the charisma/pixeltapestry features highlighted in the feature lists ? E.g. some kind of register combiners, pixel shaders, etc ...
Thanks for enlightening me, Jason !

Oh yes, one GOOD thing : PN_TRIANGLES rock !

PS : Hi Humus, how are you ? http://www.opengl.org/discussion_boards/ubb/wink.gif

[This message has been edited by paddy (edited 03-13-2001).]

03-13-2001, 06:28 AM
Hi Paddy! I'm fine, except that ATi just sort of rejected my request of becoming a registered developer ... but if you say you didn't get much out of it, well perhaps I shouldn't be too unhappy ...

03-13-2001, 07:24 AM

How did you get ATI_PN_TRIANGLES specs? Through devrel program?

03-13-2001, 07:32 AM
No there's a released doc on ati's site.
Let me search for the link ...

03-13-2001, 08:05 AM
Sorry, but it's general description of that PN triangles are, it's not extension specification.

03-13-2001, 06:19 PM
h2. The fonction definitions are in the glAti.h that they give on their website. You can easely figure it out. This extension is awesome!!

Now I would love to have fonction definition and tokens for EMBM.

03-13-2001, 10:22 PM
This is my personnal opinion and message to Jason[ATI], but i think you will all agree.

First of all, at I/O Labs, we work with both ATI and NVidia cards, and have to take advantage of both. I'm registered developper for both manufacturers. Both GF and RadeON are great pieces of hardware.

When you develop software to support an NVidia card, you just have to browse their web site to find plenty of eyecandy demos with source code and tons of papers about how to implement their hardware at the best.
On the ATI site, you can find the ATI development kit, which is not bad but too limited. I'm pretty sure the RadeON is a great card, but we need more precise informations about how to use it's fantastic capabilities. The specs of the Charisma engine and the Pixel Tapestry are in my opinion as impressive as the GF3 specs, and they are over 8 months old. Most of them are supported in DX8 with 3102 drivers, but ATI must give us some software pieces that really show their practical usage. In OpenGL it's different, and the main priority is to add some extensions to be able to use those awesome DX8 features in GL too. And i'm not only talking about EMBM. The RadeON pixel pipeline should be capable of some kind of pixel shader (a register combiner equivalent). And where is the priority buffer ?

It's too bad such a good GFX card lacks of software support. The hardware is there.

I hope my frenchie's english is not too bad ...

My half-a-cent http://www.opengl.org/discussion_boards/ubb/wink.gif

[This message has been edited by paddy (edited 03-13-2001).]

03-14-2001, 02:10 AM
What would it take to shame Dave Orton into supporting the developer community?

03-14-2001, 05:02 AM
I agree with you paddy. ATI seems real slow to put up new features in their driver and the documentation is not upated rapidly either. If there is EMBM in the drivers right now, just give the freakin' documentation to everyone! Doesn't matter if it is not totally working correctly!

Everytime you hear that you can have a new driver for Nvidia, there is always something new in it.

03-14-2001, 07:02 AM
>The fonction definitions are in the glAti.h

Well so I believe next logical step for guys from ATI is to propose to developers to hack drivers to find out how extension works! :E

paddy is absolutely right. IMHO if such "developers relations" and badly supported OpenGL will be continued, only programs from Radeon SDK will support Radeon!

03-14-2001, 08:00 AM
I fully agree with Paddy and the rest. Developer support sux. It doesn't matter how powerful the hardware is if there's no software to back it up.

03-14-2001, 11:22 PM
^ Back to top ^
Still no answer ???

03-15-2001, 08:10 AM
No comments?

03-15-2001, 10:49 AM
Yes, it would be interesting to hear from ATI.

Nvidia would have already answer something

JasonM [ATI]
03-15-2001, 10:42 PM
Chill, fellas. I've got all the specs you're asking for and will be pushing them up to the website soon. It's just that it's the week before GDC (http://www.gdconf.com/) and I'm swamped.


[This message has been edited by JasonM [ATI] (edited 03-15-2001).]

[This message has been edited by JasonM [ATI] (edited 03-15-2001).]

03-16-2001, 04:57 AM
Great news!! Yeah, we tend to be aggressive, we might be a little spoiled!!

03-17-2001, 09:16 PM
Jason, please don't forget to keep us updated when you'll have the time!

[This message has been edited by Gorg (edited 03-17-2001).]