PDA

View Full Version : vp and fp implementation details



tellaman
09-03-2003, 09:09 AM
i've been looking for some specs over the internet but i couldnt find any precise information about the following features:
vp and fp length, number of usable registers, ways of selecting fp precision on nv hardware, fsaa modes (hint tokens to switch modes within the same # of samples)
i would love to gather information on these features for dx8 and above class hardware
can anyone provide some links?
thanks for your help!

[This message has been edited by tellaman (edited 09-03-2003).]

tellaman
09-03-2003, 09:40 AM
ok, forget it, i've just gone through the specs again and it's all there
i wish i could delete this one
could you still help with fsaa modes?

al_bob
09-03-2003, 11:59 AM
For multisampling FSAA, you need to use wgl/glX to create a render context with the right attributes. Have a look at GL_ARB_multisample (http://oss.sgi.com/projects/ogl-sample/registry/ARB/multisample.txt) for details.

Supersampling and other forms of FSAA are only available through driver switches.

tellaman
09-03-2003, 05:07 PM
thanks bob, i have already implemented fsaa through the multisample extension
my problem is different though, i mean i can query pixel formats in order to know what the max amount of samples they will support is

on my 5900 they can be 0, 2 or 4 (shouldnt there be a 8x option too?)
on nv hardware one can use


glHint(GL_MULTISAMPLE_FILTER_HINT_NV,GL_NICEST | | GL_FASTEST);
to switch between the following aa modes:


Multisample kernels WGL_SAMPLES_ARB Multisample filter hint mode
2 sample/2 tap 2 GL_FASTEST
2 sample/5 tap (Quincunx) 2 GL_NICEST
4 sample/4 tap 4 GL_FASTEST
4 sample/9 tap 4 GL_NICEST


but what about ati hardware? i heard a 9500 supports up to 6 samples, but are there different modes for the same number of samples as on nv hardware?

al_bob
09-03-2003, 06:49 PM
on my 5900 they can be 0, 2 or 4 (shouldnt there be a 8x option too?)
There's no 8x multisampling mode on the 5900. The Quadro FX, however, does have an 8x multisample mode.


but what about ati hardware? i heard a 9500 supports up to 6 samples, but are there different modes for the same number of samples as on nv hardware?
I don't beleive you can dynamically switch the multisample mode on ATI hardware (I could be wrong). You need to create a render context with 6 samples to get 6x MSAA.

nVidia hardware does not support 6x MSAA.

Combinations of multisampling and supersampling can be used to achieve higher quality rendering (4xS and 8xS), but those require setting options in the driver; they're not directly accessible by the application.

tellaman
09-04-2003, 06:39 AM
thanks so much bob, this clears some things off
but another problem arose now, querying wgl pixel formats i can see that a 9800 does not support WGL_SAMPLE_BUFFERS_ARB, so now i'm left wondering how ati hardware manages fsaa iin opengl
can you provide some help?
thanks again

EDIT: no similar problems on a 9700, i'm going to investigate about driver versions...

[This message has been edited by tellaman (edited 09-04-2003).]

tellaman
09-04-2003, 09:39 AM
ok, catalyst 3.6 can solve the problem
thanks again for your help bye!