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Intel17
01-08-05, 08:09 PM
Well, I emailed Carmack about those leftover cvars in Doom 3 and if the licencees get the code, and here's what I got (some other info I got wasn't from carmack but Brian Harris of Id software).

The experimental code used pbuffers, and wasn't all that well integrated with the entire system, so no, it wouldn't be completely trivial for licensees to use it. I was also using the NV40 floating point blends, so supporting ATI cards and NV30 cards would require more code to do extra passes to simulate blending.

John Carmack

So, it's basically "beta" such as FarCry's HDR (hence why it's not a "checkbox" option in FC).
Also, it's NV40 only as well, as he hasn't done the ATi and NV30 HDR in the "EXP" rendering path (which licencees get).
Also, Doom 3 Engine has soft-shadow support in an "incomplete" state if you licence the engine, as not all the problems had been solved in the EXP path.

So what do you guys think? Isn't this pretty cool? We may actually see a Doom3 based game with HDR in it!

Now, who says D3 isn't the most advanced ;) Imaging all real-time lights using an actual HDR light probe for the lighting, if every light did that, you could simulate radiosity quite well!

aAv7
01-08-05, 08:42 PM
This is like the 3rd email you've gotten from him, he's either incredibly nice, or your incredibly full of sh*t. I'll go with it though cause your a good guy. =)

Seeing HDR in future id games would be sweet, if done correctly. After the intial "WOW" factor from hdr in farcry, I started realizing it was horribly over-exposed. Developers are still playing with this feature, hopefully by next generation they'll be able to improve the iq and performance of hdr. =)

What does doom 3 use? opgl 1.5 or 2.0?

SH64
01-08-05, 08:51 PM
Enabling HDR in a Doom3 powered game will bring even current highest-end systems to thier knees ... maybe the next generation GPUs will be able to handle it so i dont expect it to show anytime soon .. not at least in Quake4 .
& yep its good to know that D3 engine can do HDR , but i think i already heard/read about that before & now JC's mail -if correct- supports that .

BioHazZarD
01-09-05, 03:07 AM
yeah too bad it takes to much from the system.

Intel17
01-09-05, 06:50 AM
This is like the 3rd email you've gotten from him, he's either incredibly nice, or your incredibly full of sh*t. I'll go with it though cause your a good guy. =)

Seeing HDR in future id games would be sweet, if done correctly. After the intial "WOW" factor from hdr in farcry, I started realizing it was horribly over-exposed. Developers are still playing with this feature, hopefully by next generation they'll be able to improve the iq and performance of hdr. =)

What does doom 3 use? opgl 1.5 or 2.0?

I am very happy you believe me :) I've got emails from Sweeney as well, and hopefully I'll post them soon!

HDR is performance expensive...but please, don't use FarCry as an example for floating point blending HDR. FarCry's was *EXTREMELY*unoptimized, and it was just added in just so it could say "Look we have HDR rendering!".

HDR itself isn't really the issue, it's the adding HDR to games where the content wasn't designed for it, that's the true issue.

All in all, it's good to know Doom 3 Engine has HDR, and has Cg. So much for a "DX7 engine".

Enabling HDR in a Doom3 powered game will bring even current highest-end systems to thier knees ... maybe the next generation GPUs will be able to handle it so i dont expect it to show anytime soon .. not at least in Quake4 .
& yep its good to know that D3 engine can do HDR , but i think i already heard/read about that before & now JC's mail -if correct- supports that .

Well, I wouldn't doubt JC's correctness of the information he gave me. And about how you heard about it before...yeah, it was an email to someone on B3D from Carmack. But he was very vague in his answer, that's why I asked and, very luckily, I got a good reply :-)

Morrow
01-09-05, 07:23 AM
HDR is performance expensive...but please, don't use FarCry as an example for floating point blending HDR. FarCry's was *EXTREMELY*unoptimized, and it was just added in just so it could say "Look we have HDR rendering!".

HDR itself isn't really the issue, it's the adding HDR to games where the content wasn't designed for it, that's the true issue.

I'll take that you are not talking about HDR performance but about HDR image quality?

The HDR performance in FarCry will be the same as the HDR performance in Doom3 if they also use FP16-blending like in FarCry. This has nothing to do with being optimized or not, this has something to do with decreasing the available bandwidth on the nv40 cards by half and therefore decreasing also the performance by half.

There is nothing Carmack or any other coder can do about that.

Intel17
01-09-05, 07:33 AM
I'll take that you are not talking about HDR performance but about HDR image quality?

The HDR performance in FarCry will be the same as the HDR performance in Doom3 if they also use FP16-blending like in FarCry. This has nothing to do with being optimized or not, this has something to do with decreasing the available bandwidth on the nv40 cards by half and therefore decreasing also the performance by half.

There is nothing Carmack or any other coder can do about that.

Well, ok, I take back what I said about performance. However, the image quality still wont be better all around, unless the game is designed for it. That's why in some scenarios it looks worse!

anzak
01-09-05, 10:13 AM
HDR is performance expensive...but please, don't use FarCry as an example for floating point blending HDR. FarCry's was *EXTREMELY*unoptimized, and it was just added in just so it could say "Look we have HDR rendering!".

And you would know this how?

Anyways, thanks for the info. IMO HDR would have been totally waisted in a game like Doom 3, but other games such as CoD would be awesome with HDR rendering.

Edit: Nevermind :rolleyes:

Intel17
01-09-05, 11:18 AM
And you would know this how?

Anyways, thanks for the info. IMO HDR would have been totally waisted in a game like Doom 3, but other games such as CoD would be awesome with HDR rendering.

Edit: Nevermind :rolleyes:

Well it would have made lighting calculations more precise, and with all lighting real time, it may look good...but the content wasn't designed for it, so it wouldn't have made too much of a difference.

aAv7
01-09-05, 11:48 AM
The game seems too dark for HDR, but it is nice to know the feature is there in the engine.

Still curious to know if anyone knows what version of opengl doom 3 uses, 1.5 or 2.0?

Personally I thought the character/monster animation was very fluid and life-like, and the shadows were awesome as well....I just had the one complaint most had....low res walls, items,etc.....some say the game would make systems crawl had it used higher textures for walls, doors, and all other environments, but I have to think while running the game @ 60fps without an oc to my gpu @ 1600x1200 w/ 4xaa/af maybe the higher textures could have been done....I wouldnt have minded playing @ 1280x960 no aa/af for the sake of more detail..but thats me.

anzak
01-09-05, 12:58 PM
Still curious to know if anyone knows what version of opengl doom 3 uses, 1.5 or 2.0?

Should be 1.5, 2.0 is not fully supported in ATI and nVidia's drivers.

superklye
01-09-05, 02:18 PM
Should be 1.5, 2.0 is not fully supported in ATI and nVidia's drivers.
I thought 2.0 HAD been fully supported in nVIDIA's drivers?

Morrow
01-09-05, 03:27 PM
Still curious to know if anyone knows what version of opengl doom 3 uses, 1.5 or 2.0?

Contrary to what most people believe, Doom3 is for the most part OpenGL 1.4 with some 1.5 in the mix.

BTW, the OGL 2.0 specification was finalized AFTER Doom3 shipped, so that should say enough about whether D3 supports OGL 2.0 or not.

Morrow
01-09-05, 03:29 PM
I thought 2.0 HAD been fully supported in nVIDIA's drivers?

No, nvidia has almost full OpenGL Shading Language support in their drivers. This OGSL was sometimes wrongly referred to as being OGL 2.0 but it's only a part of it.

superklye
01-09-05, 04:00 PM
No, nvidia has almost full OpenGL Shading Language support in their drivers. This OGSL was sometimes wrongly referred to as being OGL 2.0 but it's only a part of it.
ahh...that must be what I was thinking of then.

Minielf
01-10-05, 03:11 AM
HDR killed farcry... And it looked horrible because of no AA... It went from 70 FPS with AA to 30 FPS without AA... Doom3 engine runs like hell... So it would probably run even worse...

Anyhow i think HDR would have been really bad in doom3 anyhow... But i would have loved to see soft shadows... Anyway doom3's engine and lighting doesnt seem all that great... Riddick's engine looks ALOT like it... And i have seen 3-4 OGL games that i thought were doom3 engine but were in fact not... So its not unique in any way... Except that it SWALLOWS resources like a little blondie...

PoorGuy
01-10-05, 05:05 PM
The good news is that this is for nVidia video cards only. It's good to have game features that specifically take advantage of hardware capabilities that the competition can't offer.

However, it seems like the programming code for HDR isn't quite as optimized as we think for any game in any video resolution given the results from FarCry.

superklye
01-10-05, 05:09 PM
Except that it SWALLOWS resources like a little blondie...
nice

anzak
01-10-05, 05:14 PM
HDR killed farcry... And it looked horrible because of no AA... It went from 70 FPS with AA to 30 FPS without AA... Doom3 engine runs like hell... So it would probably run even worse...

Anyhow i think HDR would have been really bad in doom3 anyhow... But i would have loved to see soft shadows... Anyway doom3's engine and lighting doesnt seem all that great... Riddick's engine looks ALOT like it... And i have seen 3-4 OGL games that i thought were doom3 engine but were in fact not... So its not unique in any way... Except that it SWALLOWS resources like a little blondie...

Do you have a 6800 series card? Because if you did you would know that Far Cry looks awesome with HDR (in some parts) despite not having AA enabled. Also, Doom 3 runs awesome on a 6800GT, 1600x1200 w/2xAA is totally smooth.

Beng
01-10-05, 07:40 PM
The good news is that this is for nVidia video cards only.

Not necessarily true. Tim Sweeney from Epic (Unreal) will make FP16 HDR possible for current Ati hardware with a workaround.

The only special consideration on that hardware is its lack of floating-point blending. To work around that, we swap to a new render target, and perform manual blending in a shader program, using the original render target as a texture. This is slower than real floating-point blending, but only affects total performance by 20% or so

http://www.beyond3d.com/forum/viewtopic.php?t=19472

Intel17
01-10-05, 07:59 PM
Hehe, my emails from these famous devs sure do get around! ;)

red_star
01-10-05, 09:04 PM
HDR = useless...

1. Can't trade off AA for HDR.
2. Huge performance hit.
3. Doesn't make a game to look realistic. However it looks bad in a certain areas. Unrealistic lights in many cases...
4. I would like to see displacement mapping rather than HDR crap
5. Glow effect used in HL2 gives much realistic picture than HDR
6. I will never use it in the future...

anzak
01-10-05, 09:14 PM
HDR = useless...

1. Can't trade off AA for HDR.
2. Huge performance hit.
3. Doesn't make a game to look realistic. However it looks bad in a certain areas. Unrealistic lights in many cases...
4. I would like to see displacement mapping rather than HDR crap
5. Glow effect used in HL2 gives much realistic picture than HDR
6. I will never use it in the future...

1. Not true, you can't use AA with OpenEXR HDR.
2. Depends on how it is implemented.
3. HDR is required to make photo realistic images. If your talking about the HDR in Far Cry then yes, but Far Cry was not designed with HDR in mind.
4. Crap?
5. Im not even going to comment on this. :rolleyes:
6. You may not have a choice.

Can you make a positive post? In every one of your post you call something Crap.

Beng
01-10-05, 09:25 PM
Not true, you can't use AA with OpenEXR HDR.

I hope future gen (R520/Nv48) will work this out (i think it will), that's why i don't spent my money on a Nv40 Sli rig.

AngelGraves13
01-11-05, 02:49 AM
HDR = useless...

1. Can't trade off AA for HDR.
2. Huge performance hit.
3. Doesn't make a game to look realistic. However it looks bad in a certain areas. Unrealistic lights in many cases...
4. I would like to see displacement mapping rather than HDR crap
5. Glow effect used in HL2 gives much realistic picture than HDR
6. I will never use it in the future...

Damn...who crapped in your cornflakes? Future cards will have AA in HDR and the performance hit won't be big, AND will look better than Far Cry.