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ATi frame buffer read speeds

The Khan Artist

Warrior for God
Well, Pete just updated his PSX GPU plugins with a special "ATi release", and here is an exceprt from the changelog:

# Now I started up several psx games which are known to use framebuffer textures/framebuffer access. Nice: in OpenGL the framebuffer texture option works very fast on ATI cards (at least on the R9700 Pro). But the framebuffer access (reading vram to system memory) has an horrible speed... at least 5 times slower than my old GF3. I've tried all kind of different color formats, and read through the ATI OpenGL extension specs, but no luck: slow. So I decided to do a new 'special game fix' (I should rename that section into 'special hardware fixes', it seems), calling it 'Mixed software FB access'. What does it do? It minimizes the real vram reading to a minimum, whenever the 'framebuffer access' modes 1 (reads), 2 (moves) and 3 (read&moves) are used, and uses software drawing instead. Unlike the FB access mode 4 (full software drawing) it will not use the soft funcs all the time, only if they are really needed, when a psx game is doing such special effects.

# Then I moved on to the D3D plugins... didn't expect much problems, but then I noticed an horrible slowdown with 'FB access' and even with 'FB textures'. Well, I did know that my D3D code to emulate such effects were optimized for older (DX6/7) hardware, but I never suspected that newer ATI cards were choking that bad at it. Anyway, since the new OGL plugin is working really nice on new cards, I didn't change anything with the D3D code, I just added the new 'Mixed software FB access' special game fix as well. Therefore: if you want to play psx games with my plugins with an ATI card, I suggest to use the OGL plugin. If (for whatever reasons) you want to use one of the D3D plugins, you should at least enable the new fix, and set the 'FB textures' option to 3 (card buffer + software), never to 2 (card buffer).

I thought I read something that with recent driver updates, the Radeon 9700 Pro was about 5 times faster than anything else at copying framebuffer to system memory. So is it really not? Or is Pete doing something wrong?
 

Tagrineth

Dragony thingy
That's odd. Even the pre-battle swirly effects in some games (Tales of Phantasia and Final Fantasy IX come to mind) stay at 59.9FPS on my Radeon 9500 Pro, using Pete's D3D6 older version. He must be doing something wrong... or maybe it's just one of ATi's famous driver bugs (tm).
 

Orkin

d1R3c764 & g1|\|64 m4|<3R
I've found framebuffer access to be very slow on my Radeon 9500 Pro while working on framebuffer stuff for glN64. I had heard it was faster too, but apparently either recent driver releases slowed it down again, or there never was any truth to it.
 

nephalim

Psychic Vampire
With my M9 (Radeon 9000 equivalent,) I turned on full frame buffer emulation with Jabo's 1.5.1 while playing Majora's Mask. Not a single smidgen of a performance hit. How exactly does the card pull this off?
 

nephalim

Psychic Vampire
Sorry, should have said, they were the Dell A03 drivers. Guess that doesn't help you much, sorry...

EDIT: The cards can definetely do this, my ATI M4 did decent framebuffer reads with Jabo's 5 (not older), it's just bad driver fever over at ATI. I think the catalyst 3.1 drivers are the best at the moment, at least i've heard that, twice I think? Try Jabo's 5 and turn on frame buffer emulation (turn off emulate clear,) and see what happens. I think it's some special function that Jabo's uses, but i'm speculating.
 
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Tagrineth

Dragony thingy
Catalyst 3.2 ran perfect, but I haven't tested anything with cat3.4 yet, and I don't have cat3.5 yet. Yay.
 

nephalim

Psychic Vampire
I have had no issues at all with the Dell drivers so far, and they seem pretty nice, they got all the options and controls for settings that are mobile exclusive.
 
OP
The Khan Artist

The Khan Artist

Warrior for God
Is there any good place to get old drivers? The DriverHeaven downloads don't seem to be working... and did Omega make a hacked 3.2?

EDIT: Yeah, it seems he did. Now I just have to find a place to download them. :p

EDIT2: Woohoo, found 'em. Me be having fun tonight!

I _am_ going to install 3.4, at least temporarily, so I can check out the nVidia Dawn demo. With the Cat 3.1 that came with my card, it complains about a missing ARB_multitexture extension. And the readme for the nVidia->ATi wrapper says it needs 3.4 anyway.
 
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AlphaWolf

I prey, not pray.
I use the catalyst drivers on my mobility, the 3.2 drivers are absolute shit though. 3.4 and 3.5 *work*, but 3.1 is by far the best.
 
OP
The Khan Artist

The Khan Artist

Warrior for God
I tried 3.1 with Jabo's D3D6 1.4. I don't know why I chose that plugin, but that's all I had time to try last night.

Framebuffer performance was horrid, and Jabo's plugin refused to do FSAA.

Milkdrop ran vastly better than it ever has before, though. :D
 

nephalim

Psychic Vampire
No no use Jabo's 1.5, 1.5 had it's framebuffer engine completely rewritten, which is what made framebuffer emulation feasible on my old M4. With 1.4, the performance was horrible.

I think there is some special method for fast framebuffer that needs to be specially coded, for ATi cards.
 
The Khan Artist said:
I tried 3.1 with Jabo's D3D6 1.4. I don't know why I chose that plugin, but that's all I had time to try last night.

Framebuffer performance was horrid, and Jabo's plugin refused to do FSAA.

Milkdrop ran vastly better than it ever has before, though. :D
Did you download the ATI control panel?
And if so, turn off Application preference (for antialiasing), and set your settings for antialiasing, and Jabo's plugin should see antialiasing available.
 
OP
The Khan Artist

The Khan Artist

Warrior for God
Well, I installed the Cat 3.5 drivers (yes, and Control Panel), and this is what I get with Jabo's 1.5.

Take a good look at the yellow fences in Zelda - see how they don't get antialiased? And yet most other surfaces do. Same with aniso.
 
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OP
The Khan Artist

The Khan Artist

Warrior for God
Unreal Tourney looks horrid too... some polygons flicker, and there are z-buffer problems with some of the lights.

Using the UTPG Path 451 with the D3D renderer.
 
OP
The Khan Artist

The Khan Artist

Warrior for God
OK, I installed Omega's hacked 3.2 Cats... Unreal Tourney looks almost perfect, except for the fact that it doesn't get FSAA. Nothing does. Jabo's plugin doesn't even detect that my card supports it.

*sigh*
 

nephalim

Psychic Vampire
Your problems lie in the horribly bugged catalyst drivers, but I think you already know that. Try 3.0/3.1
 

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