DOOM 3: 512mb!! what about 3Dc???

Z

zz2

Limp Gawd
Joined
Jun 28, 2004
Messages
181
ATI does not support the palettized compression so we needed a better solution.
Click to expand...

I wonder why they didn't try 3Dc since ATI is saying that it is used in Ruby demo to compress normal maps, so you don't need 512MB graphic card.

EDIT: ...so you don't need 512MB graphic card to run Ruby demo. That is what I meant to say in first place but i gues I dident say it right. :rolleyes:
Sorry for my english ;)
 
Ahem...
http://www.nvnews.net/vbulletin/showthread.php?t=30772&highlight=3dc


http://www.gamespot.com/news/2004/07/26/news_6103458.html
ATI vs. Nvidia cards: "One thing of note on the normal map compression is that, generally speaking, if you DXT a normal map you get really crappy results. NVIDIA hardware supports palettized compression, which yields good compression, and normal maps retain hard and round edges really well. Unfortunately, this compression does a poor job in other cases and you end up getting splotchy areas. ATI does not support the palettized compression, so we needed a better solution. ATI had done some research on various methods of normal map compression, and we ended up swapping the red and alpha ( which is zero in the case of a normal map ) channels. This effectively allows the compression to do a much better job and is just one extra instruction in the fragment program to move the alpha channel into the red channel."
Click to expand...
I think it's always best to quote the whole thing instead of ripping anything out of context. ;)
 
zz2 said:
I wonder why they didn't try 3Dc since ATI is saying that it is used in Ruby demo to compress normal maps, so you don't need 512MB graphic card.
Click to expand...
You still DO need 512MB graphic card.
 
ShePearl said:
You still DO need 512MB graphic card.
Click to expand...

why?? if it is compressed it is smaller right?

in this article it says:

High quality uses compression ( DXT1,3,5 ) for specular and diffuse and no compression for normal maps. This looks very very close to Ultra quality but the compression does cause some loss. This is the quality that for instance the PC Gamer review was played in.
Click to expand...

so with High quality you are able to play the game with 256MB card but DXT compression cause some loss. But since 3Dc do better compresion (sorry but i am not sure if 3Dc can be used for compressing other images (non normal maps)but if it can... than they should use 3Dc instead using DXT and difference betwen uncompresed (Ultra quality) and compressed with 3Dc should be minimal and there would be no need for uncompressed mode.
 
CHILL..... your argument is dumb because you need 512 for a COMPLETELY UNCOMPRESSED setting.

not even high settings use compressed normal maps so that is useless too, so they would only use 3dc in medium and low quality settings, which requires no more than 128 anyways
 
Exactly. The whole point of DOOM3 requiring 512MB of video memory is for *uncompressed* settings for the best, and maximum visual quality.

3Dc which only applies to normal maps does provide somewhat slightly better quality compared to DXT5. But all of those compressions are *lossy*. Hence degrade in IQ.
 
well maybe I didn't say it right before, but my point was why would you use uncompressed settings. yes uncompressed is always better than lossy compression but where would we be now if we woudn't use compression. Do you know how big is uncompressed movie. you can't play it on slower HD because HD cannot read that fast. and why is everybody using jpeg??

yes I know that you need 512MB video card for *uncompressed* settings, but why use uncompressed. because of higher quality?? i would rather used compressed and with higher resolution.

and what I was trying to say is that if they wanted to increase quality they should use 3Dc for normal maps and lower (or no) compression for specular and diffuse. yes I don't know if this would lead to even lower IQ that High quality but i gues not since 3Dc compression looks fine to me. so i was asking if they used 3Dc could they increase quality of of specular and diffuse and fit that into 256mb card?? would it be better than High quality settings?? i think that there is no need to use fully uncompressed settings and therefore require 512MB card. it would be perfect if they could use 2048*2048 resolution textures and models with 300.000 poligons instead 5000, but they can't so they have to find perfect ratio and using uncompressed textures and requireing 512MB graphic card doesn't make sense to me.

here is picture that shows difference between uncompresed, DXT and 3Dc

3dc-comp-sample.jpg
 
ShePearl said:
Exactly. The whole point of DOOM3 requiring 512MB of video memory is for *uncompressed* settings for the best, and maximum visual quality.

3Dc which only applies to normal maps does provide somewhat slightly better quality compared to DXT5. But all of those compressions are *lossy*. Hence degrade in IQ.
Click to expand...

3dc is a lossless compression scheme.
 
gordon151 said:
3dc is a lossless compression scheme.
Click to expand...
Is that from your imagination ? 3Dc is lossy. Not lossless. It's FAR from being lossless.
 
COCOViper said:
um...i dont know of any image or video compression that is totally lossless....
Click to expand...

Off hand I don't know of any lossless video, but I'm sure there are several. Now for images i know of several lossless compression schemes. There is raw, png, and gif (if colors <=256). I'm sure there are also more out there. Just because there is compression doesn't mean it is lossless. Just look at a zip or rar archive. You aren't losing any information when you shrink it.
 
CyberCRAP said:
Off hand I don't know of any lossless video, but I'm sure there are several. Now for images i know of several lossless compression schemes. There is raw, png, and gif (if colors <=256). I'm sure there are also more out there. Just because there is compression doesn't mean it is lossless. Just look at a zip or rar archive. You aren't losing any information when you shrink it.
Click to expand...

yea i know zip and rar are lossless, but thats also why they dont compress images or video much if at all (maybe 5-8% if you're lucky)

Isnt raw and png almost the same size as bmp ?

and are you sure gif is lossless ? (remember even if its almost perfect- its still not lossless)
 
PNG isn't near the size of a bitmap, but I don't think its lossless either. It does have some nice features though, like alpha transparency.
 
I don't think at 4:1 that 3Dc is loseless. Thats why we should be pushing for a programmable texture compressor, so that innovations made in compression (Like in Divx, Xvid for video and PNG for images) can be immediately be put into videocards. You could easily make a loseless compressor at 2:1, but I'd rather have 4:1 lossy at double the texture resolution (has been proven a good chunk of times to look BETTER than an uncompressed at regular resolution, even with DXTC1.)

PNG is loseless.

3Dc will only do so much, it will not magically make your 128MB card equivalent to a 512MB. I'm pretty sure you still need a 512MB card to run Doom3 at ultra quality, its just that if you have a 256MB or 128MB card, 3Dc has the potential to look and perform a lot closer to what was orginally intended. If it ever gets patched to use it.
 
3Dc feels like a natural progression, but also a pretty important leap in compression IMO. Sort of like how OGG is compared to MP3 for audio. OGG tends to sound better at the same bitrate, or you can use it for smaller files at the same approximate quality. I hope this finally validates OGG as a codec, I never really liked MP3's (lack of) audio quality.

Its important to mention OGG audio along with the video capabilities, because once you start going out of the bounds of videocard memory, you can start to eat away at main memory, which is filled with all sorts of audio samples and can definitely affect performance.
 
3dc is practically close. Humus's demo demonstrated that much when no one could see any visual artifacts in the maps compressed with 3dc even while zoomed. Also the fact that even the hq mode doesn't use compressed maps and it fits well into a 256mb card according to them, hints at the scenario that had they used some type of compression, a 512mb card wouldn't necessarily be required for uhq. 3dc might have gotten rid of the visual anomalies they saw with dxt and eased the ram requirements, but it doesn’t look like they tried that route.
 
When it comes to video I don't like OGG as much (I have iTunes modded for OGG though) I've notice that it takes up too much CPU for playback (compared to others).
 
gordon151 said:
a 512mb card wouldn't necessarily be required for uhq. .
Click to expand...


Accordingly to what John Carmack said somewhere( can't remember where, htere has been so such hype over Doom3 that I last track of it all :) ) that a 512 MB videocrad was required for Ultra Quality...the way it was meant to look(and be played) ;)

Terra...
 
Xipher said:
Ogg/Vorbis is used for Audio.
Click to expand...
Then why do I have an OGG codec with my other video codecs? ;)
Also why do I have some OGG video files then? ;)
 
There are video codecs that use OGG/Vorbis for the audio.
http://www.vorbis.com/
Ogg Vorbis is a completely open, patent-free, professional audio encoding and streaming technology with all the benefits of Open Source.
Click to expand...

also, in Robert Duffy's recent .plan update he said they actually use ogg for some of the audio in DooM 3
Sound diversity is effectively how many sounds we support per sound shader for a given "sound". There may be for instance, 7 different "bullet striking the wa
ll" sounds for a given bullet. In low quality, we only use one sound for this vs randomly choosing between one of the seven available. When we started on memo
ry optimization, most levels used between 80 and 100 megabytes of sound data. We made the choice to move to .OGG for quite a few sounds which effectively remo
ved the problem for us.
Click to expand...
 
Yea, 3DLabs is a pretty good company for High end graphics cards. although, they are pricey
 
CrimandEvil said:
Then why do I have an OGG codec with my other video codecs? ;)
Also why do I have some OGG video files then? ;)
Click to expand...

Hmmm while you might have files with VP3 video codec, more likely it seems they are OGM files with some other video codec (XVid most likely if its OGM or potentially Divx). OGM needs to be used if you use Ogg Vorbis for audio due to AV syncing issues with AVI with Ogg Vorbis.

Also 3Dc can't be used for other images, well it can just as long as you don't want anything besides a Red and Green channel (or you could swizzle if you want some other combination of 2 channels). And at this time as far as I know you can't use 3Dc in OpenGL at the moment due to ATI hasn't added an extension for it yet :(
 
I was thinking, the two channels have to be 1:Red and 2:BlueGreen

It would be pretty easy to combine blue and green into one at half precision of the red (Backwards idea of doubling the red bits by using the unused alpha)
 
OGM rocks for PocketPC video with audio. Squeezing a 3 hour movie with 22.050hz stereo at ogg quality -1 onto a 256MB flash card just kicks ass. If anyone wants a sample link to an OGM, just PM me.

OGG does take a tiny amount more processing power, depending on how strong/weak your floating point unit is (portables tend to not even have a floating point calculator, so its moot and will always be harder on the CPU than MP3) But on a desktop CPU, I can't imagine it would take more than 1 percent more CPU usage if any.
 
If you need just 3 Channels why wouldn't you just use DXT1 though :p

Doesn't matter which channels you want with 3Dc since you can do a swizzle in the PS(change which color maps to which).
 
gordon151 said:
3dc is practically close. Humus's demo demonstrated that much when no one could see any visual artifacts in the maps compressed with 3dc even while zoomed. Also the fact that even the hq mode doesn't use compressed maps and it fits well into a 256mb card according to them, hints at the scenario that had they used some type of compression, a 512mb card wouldn't necessarily be required for uhq. 3dc might have gotten rid of the visual anomalies they saw with dxt and eased the ram requirements, but it doesn’t look like they tried that route.
Click to expand...

but practically close isn't what we were talking about.

We're talking about the MAX Ultra Quality for textures. 3DC might be a really good choice for say High Quality...but not Ultra High. Ultra High with uncompressed textures will always look better- its the nature of compression.

The people that spend tons and tons of $$$ on hardware, want to be able to max it out. (and anyone who disagrees is someone that just fears their hardware won't keep up really)
 
tornadotsunamilife said:
but isn't mp3 already compressed? it's like compressing something compressed already
Click to expand...

Ya good point, forgot about that. What about avi though?
 
The Batman said:
Ya good point, forgot about that. What about avi though?
Click to expand...

avi is compressed, divx, xvid, ms mpeg4, all compressed, all use .avi extension, although you can have raw video as .avi it's HUGE and i'm fairly certain the avi you're speaking of is divx/xvid therefore being compressed.
 
zz2 said:
i would rather used compressed and with higher resolution.
Click to expand...

well then feel free, thats what medium settings are for, ya goofus :rolleyes:

zz2 said:
if they wanted to increase quality they should use 3Dc for normal maps and lower (or no) compression for specular and diffuse.... i think that there is no need to use fully uncompressed settings and therefore require 512MB card.
Click to expand...

i think i would rather have id making the decisions on how they make their games :)
 
You must log in or register to reply here.
Back
Top