Alpha test -> alpha to coverage tool

[tEd]

Humus,

with the new opengl32.dll alphatocoverage doesn't work anymore in serious sam second entcounter and with halflife i get a setpixelformat error

 

[Geo]

Ah, thanks again, that pretty much ties up the loose ends for me. So, I'll be hopeful some @ati.com are in on the action one way or another <kaff>, and look forward to Cat 5.9 or so.

Edit: And, btw, mad props to NV for getting the conversation going. Ain't it funny what it takes some times to kick the can down the road a piece.

 

[Xmas]

Edit: And, btw, mad props to NV for getting the conversation going. Ain't it funny what it takes some times to kick the can down the road a piece.

Well, considering this came up 3 years ago, it's nice to see someone deliver...
http://www.beyond3d.com/forum/viewtopic.php?t=2230
http://www.beyond3d.com/forum/viewtopic.php?t=13859

 

[tEd]

In MOHAA i get black squares within the alpha test objects

Works great in ut,rune

 

[Geo]

Yeah, I dunno that NV was in a position to pursue something like this just about then. <kaff> And ATI already owned the "Our AA kicks yo' ass" tiara. Gotta love competitive pressure tho in moving these byway things forward in the end. And then one step leads to another.

 

[KimB]

For minification, alpha-blend and alpha-to-coverage do indeed give better results. With magnification however, they result in blur.

But it's going to look bad when your texels are large compared to pixels anyway. Best to just use higher-resolution textures and go for the alpha blend/coverage instead. The minification problem is vastly harder to solve, and since the alpha blend/coverage solves it so well, it makes a whole lot more sense than supersampling.

 

[Humus]

A DirectX version of the tool:
http://www.humus.ca/Cool/DXOverride.zip

 

[BrynS]

Thanks Humus!

I've just fired up Half Life 2 to take a few shots and have been impressed with the results in motion. There seems to be no noticable performance degradation with Alpha-To-Coverage enabled on my rig (XP2400+, 1GB RAM, 9800Pro @ stock with Cat 5.6) in the brief time I've taken these shots.

All in-game graphic options were at maximum with V-Sync enabled, AA & AF settings as specified:

1024x768 Normal Rendering with 4xAA & 16xAF:


1024x768 Alpha-To-Coverage Enabled [6xAA] with 4xAA & 16xAF:



1024x768 Normal Rendering with 4xAA & 16xAF:



1024x768 Alpha-To-Coverage Enabled [6xAA] with 4xAA & 16xAF:


1600x1200 Normal Rendering with 6xAA & 16xAF



1600x1200 Alpha-To-Coverage Enabled [6xAA] with 6xAA & 16xAF:


I did get the following rendering when I had Alpha-To-Coverage enabled, but disabled AA from within the game -- does Alpha-To-Coverage only work when "global" AA is enabled?

1600x1200 Alpha-To-Coverage Enabled [6xAA] with 0xAA & 16xAF:


Cheers,


BrynS

 

[Ostsol]

Doesn't seem to be much difference. Then again, the effectiveness depends on the alpha test reference value. If it's too high, then alpha-to-coverage won't do much of anything.

 

[Humus]

The alpha test reference value doesn't affect it at all. The alpha is mapped directly.

It seems alpha-to-coverage doesn't give the improvement in HL2 one would expect. I think they don't use mipmaps, which would explain it. I'll probably add an option to generate mipmaps automatically that hopefully should improve it.

 

[Pete]

Can you whip up a quick one to work in GTA:SA for me?

Heh, GTA:VC (I'm behind the times) has blue edges galore with its lots of alpha textures, at least with my 9800P and global AA.

Pity about its D3Dness.

 

[o.d.]

flight sims?

Does this only works with Alpha textures, so regular textures still are not affected (still get the shimmies)?

I really want to get a fix for the texture aliasing..... anyway I thought I would give it a try with Flight Simulator 2004.

I tried out the DX one with Fligh Simulator 2004 (fs 9) and it would not start stating that the version of DX was not correct or something similar.

I don't even know if this AA_coverage thing will work for textures, but if it does.... well... I would be happier .

anyways, thanks for this. Really great work!

 

[KimB]

Re: flight sims?

I don't even know if this AA_coverage thing will work for textures, but if it does.... well... I would be happier .

No, won't do a thing. The best remedy for that is just adjusting the LOD bias.

 

[jb]

btw Thanks Humus!

 

[Guden Oden]

Doesn't work on NV 6800 at all. Or at least not in world of warcraft, the one game in the universe right now that would need some of this loving.

Can someone hack up a NV-compatible hack that does this? Can the driver files be binary-zapped to accomplish this perhaps?

 

[davepermen]

as all driver should support supersampling as well as multisampling anyways, it shouldn't be _that_ hard to enable if if a user calls glEnable(GL_ALPHA_TEST), on a per call basis?

should be implementable on any hw that can do multisampling and supersampling imho...

 

[sonix666]

Doesn't work on NV 6800 at all. Or at least not in world of warcraft, the one game in the universe right now that would need some of this loving.

Can someone hack up a NV-compatible hack that does this? Can the driver files be binary-zapped to accomplish this perhaps?

Well, I got alot of shimering pixels in the background in WoW on a Radeon X800 Pro. So I don't think its the NV.

 

[WKjun]

Hi!

I'm highly interested in this project. So I've tried the demo and I was even more excited! Great job Humus!
After that I've downloaded the modified OpenGL32.dll & .ini and I tried it with Soldier Of Fortune 2. I know it hasn't been tested with this game but it doesn't seem to work propably. I've tried virtually every combination of settings from the INI file and ATI-driver/game. If I leave it as it was (ForceAlphaToCoverage=0), it doesn't do a thing. If I change it to 1 it does antialias but adds a black background to every alpha texture (grass, fence, ...), so they are no longer opaque. Is there a setting to correct this?

Thanks and best regards!

 

[tEd]

Hi!

I'm highly interested in this project. So I've tried the demo and I was even more excited! Great job Humus!
After that I've downloaded the modified OpenGL32.dll & .ini and I tried it with Soldier Of Fortune 2. I know it hasn't been tested with this game but it doesn't seem to work propably. I've tried virtually every combination of settings from the INI file and ATI-driver/game. If I leave it as it was (ForceAlphaToCoverage=0), it doesn't do a thing. If I change it to 1 it does antialias but adds a black background to every alpha texture (grass, fence, ...), so they are no longer opaque. Is there a setting to correct this?

Thanks and best regards!

try to force pixelformat 15 or16.

 

[Humus]

If it's black you probably didn't get multisampling. You need to select a multisampled pixel format in the .ini file. Just forcing it in the driver won't help.