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innuendo
06-30-2008, 05:00 AM
As I know ATI Radeon HD 4800 has released.
What about new extention?
How long will we wait for ATI ?
I had been waiting while year for EXT_geometry_shader4 and ect...
I was looking for new extention for http://www.amd.com - I did not found anything.

Maybe someone was lucky than me ? :)

Zengar
06-30-2008, 05:39 AM
ATI didn't release any DX10-feature extensions for OpenGL, so I don't think they will in any close future.

Madyasiwi
06-30-2008, 11:13 PM
I'm almost believing in that there are some sort of arrangements between ATI and Microsoft to intentionally impair OpenGL. Effectively making OpenGL and, consequently, alternate OS like Linux and Mac OS a less attractive gaming platforms. :mad:

Zengar
06-30-2008, 11:34 PM
I don't think so. ATI just goes the path of the smallest resistance. There are no big OpenGL games or commertial applications that would rely on GLSL or latest extensions, so ATI just does not implement them. Bad OpenGL support does not hurt the sales. It is true that this makes lives of GL programmers on windows and linux harder... and about Mac: as Apple writes the implementation themself, it has many latest features on every card.

Groovounet
06-30-2008, 11:56 PM
The funny this with that is that "S3" with there last chip, support all those new features (instancing, geometry shader) in their OpenGL drivers...

CrazyButcher
07-01-2008, 04:06 AM
I agree with Zengar, but think that with GL3 (whenever that comes) Ati will also ship functionality again. Atm there just isnt enough "need" for implementing those features, when you know that GL3 will come anyway, and when you are naturally not as likely to push those resources.

tamlin
07-01-2008, 05:18 AM
... but think that with GL3 (whenever that comes)
You mean if? While I don't want to turn this thread into a non-GL3 flamefest (there's a better thread already for it), I feel I must voice my concern.


... when you know that GL3 will come anyway
We do? We hope, but ARB and especially Khronos has been totally silent, despite earlier promises! For now, I only target the "older" API and way of doing things - any potential GL3 isn't even considered anymore, unfortunately.

V-man
07-01-2008, 05:50 AM
Has anyone emailed AMD/ATI about this?

I am aware we are talking about Windows but as far as Linux,
I wonder if on Linux some decent drivers were made for these latest ATI GPUs. Sorry, I'm out of touch with the latest developements. Last I heard was that AMD was releasing documentations on all their GPUs.

Eosie
07-01-2008, 12:07 PM
ATI Linux drivers have exactly the same feature set as on Windows except some platform-specific stuff.

Brolingstanz
07-01-2008, 12:28 PM
I'm not much for speculation and half-cocked prognostications (hoot!), but I imagine ATI will release those extensions when to them it makes sense for them to do so, probably for the reasons Zengar and CrazyButcher mentioned.

Jan
07-01-2008, 01:49 PM
A friend of mine just got a Radeon 4850 and it seems the maximum number of vertex-shader uniforms, is as low as 512. Can anyone confirm this? Is it just an issue with early drivers ? If not, it would be a real pain, skinning is practically impossible with so few uniforms.

Jan.

Brolingstanz
07-01-2008, 02:11 PM
I can neither confirm nor deny it, but I can say that 512 seems suspiciously low for a Dx10 card.

Rob Barris
07-01-2008, 11:00 PM
Modus, I like your sig.

( My vote is for SIGGRAPH 2008 instead of bust. )

innuendo
07-02-2008, 12:14 AM
A friend of mine just got a Radeon 4850 and it seems the maximum number of vertex-shader uniforms, is as low as 512.

Jan.

Ask you friend - what about MAX_VARYING on 4850 ?
And MAX_COLOR_ATTACHTES ?

Thanks :)

Jan
07-02-2008, 03:11 AM
68 varying floats = 17 vec4's
max 4 color attachements

Something around 64 varyings seems to be standard. But 4 color-attachments is, IMO, low for the latest product. My Geforce 9600 can do 8.

Jan.

innuendo
07-02-2008, 05:04 AM
68 varying floats = 17 vec4's
max 4 color attachements

Something around 64 varyings seems to be standard. But 4 color-attachments is, IMO, low for the latest product. My Geforce 9600 can do 8.

Jan.

Thanks.

My 8600GT can do 8 color-attachments. And 60 varyings

Timothy Farrar
07-03-2008, 06:48 AM
I'll place a bet that ATI/AMD doesn't have basic DX10/SM4.0 hardware level support in their GL drivers even when(/if) GL3 is finished. And yes I would love to be wrong here.

Do they even have working vertex texture fetch now (for the HD cards)?

As for Apple, anyone know if their current DX10/SM4.0 level support (ie unified shader, VTF, geometry shader, etc) for AMD HD cards real or just simply software emulated via LLVM?

bobvodka
07-03-2008, 02:27 PM
Well, last official word was that GL3.0 was DX9 level hardware so not having a DX10 level feature in it would.. ya know.. make sense....

innuendo
07-04-2008, 12:15 AM
68 varying floats = 17 vec4's
max 4 color attachements

Something around 64 varyings seems to be standard. But 4 color-attachments is, IMO, low for the latest product. My Geforce 9600 can do 8.

Jan.

Sorry. Can you check EXT_packed_depth_stencil on Radeon 4800 ?

Komat
07-04-2008, 12:43 AM
Sorry. Can you check EXT_packed_depth_stencil on Radeon 4800 ?

Since it is supported on the Radeon 3870 I assume that it is also supported on the 4800.

Jan
07-04-2008, 12:44 AM
Well we used that in our application and it was horribly broken on the 48xx, disabling stencil test fixed some problem (but of course deactivated some feature as well), but it is very difficult to say, whether packed_depth_stencil is usable or not, because we didn't intend to repair it.

My friend exchanges his card today for a Gf 9600, so i can't dig deeper, sorry (though i'm really happy i don't have to, right now).

Jan.

Sunray
07-04-2008, 01:16 AM
I've noticed that you can't sample from a 24 bit depth texture (GL_DEPTH_COMPONENT24, GL_DEPTH24_STENCIL8) on Radeon 4850. All you get is random values. However DEPTH_COMPONENT16/32 works fine.

innuendo
07-04-2008, 01:35 AM
My friend exchanges his card today for a Gf 9600,

Jan.


Thanks. For your friend it is best idea. :)

innuendo
07-04-2008, 01:39 AM
I've noticed that you can't sample from a 24 bit depth texture (GL_DEPTH_COMPONENT24, GL_DEPTH24_STENCIL8) on Radeon 4850

What about simple rendering to FBO with stencil ?
Does it works ? Have you got any problem ?

Sunray
07-05-2008, 01:15 AM
It seems to work. My graphics engine relies on FBO with stencil and at first it didn't work at all with R4850. Then I added an additional color target to store and sample depth from and made the native depth/stencil buffer a renderbuffer. Then everything works as it should, I think.

But the consequence of this is that I got really poor depth precision from packing a depthvalue into a RGBA8 color target. But it's just a temp solution until the drivers get fixed.

innuendo
07-07-2008, 04:50 AM
It seems to work. My graphics engine relies on FBO with stencil and at first it didn't work at all with R4850. Then I added an additional color target to store and sample depth from and made the native depth/stencil buffer a renderbuffer. Then everything works as it should, I think.

But the consequence of this is that I got really poor depth precision from packing a depthvalue into a RGBA8 color target. But it's just a temp solution until the drivers get fixed.

Thanks. It is very pity !
I will not get fun with ATI :)

Jan
07-07-2008, 05:02 AM
I doubt the drivers will be "fixed" any time soon, if at all. ATI seems not only to have dropped gl 2.1 support (by not improving it anymore), but they actually remove features/functionality. I really don't know what they are trying to achieve with that, other than [oh cool, this forum censores stuff...] people off.

Jan.

Sunray
07-07-2008, 05:13 AM
I guess they have to if they want support games running id tech 5 (Rage, Doom 4).

Question: Is it possible to use ATI Fetch4 for shadow maps in OpenGL? I find zero info on the net.

Jan
07-07-2008, 08:27 AM
Sure:

if BinaryName == "Doom4.exe"
DisableCrapMode ();

NULL_PTR
07-22-2008, 04:07 AM
Catalyst 8.7 brings
GL_ARB_color_buffer_float

GL_ATI_shader_texture_lod
Only for backward compatibility, because they have this: http://www.everfall.com/paste/id.php?6x4t0zkfhz0a

WGL_ARB_pixel_format_float
The same as WGL_ATI_pixel_format_float

innuendo
07-22-2008, 08:28 AM
GL_ARB_color_buffer_float

GL_ATI_shader_texture_lod
Only for backward compatibility, because they have this: http://www.everfall.com/paste/id.php?6x4t0zkfhz0a



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