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liquidlion
08-26-2006, 07:51 AM
Are there any benifits to compressing things (textures, audio, ect.) in a game?
People over on another fourm were dogin the Resistance team saying that the only reason the game was 22 gigs was because of them being to lazy to compress stuff.

CARTIER90
08-26-2006, 07:59 AM
From what I understand, it is better to have un - compressed data than compressed for the simple fact that it takes CPU time to 'unpack' such compressed textures.....I only have a faint understanding of all things technical, im sure someone else would know here ?

What has surprised me about the 360 versus PS3 argument has been the absence of any devs stating that there game will be on PS3 due to their inability to cram the amount of data onto a DVD.
The Getaway team has stated this back in E3 2005, something about being able to sustain the 'fidelity' of the video they were then showing. Again such a lack of comments is another indicator of aiming towards the lowest common denominator - DVD. We cant blame them, who doesnt want to make money on 3 systems (including PC)....

liquidlion
08-26-2006, 08:09 AM
So that would mean uncompressed data= faster load tome right? Also couldn't dev's compress data for the 360/pc and just leave it uncompressed for the ps3?

Luis
08-26-2006, 08:30 AM
I'm afraid they ignore that the disc will include several audio languages. Audio can't be heavily compressed withouth a huge loss of quality. I wouldn't be surprised if all of the voice acting in all languages required 5 GB in TrueHD Dolby Digital or DTS, which is unthinkable for a 360 title. However, that's not all.

There are different kinds of compression. Lossy one used for audio and video and non-lossy used for other kinds of data. Non-lossy compression isn't usually very effective, which means that 22 GB wouldn't magically become 7 GB without getting rid of a serious amount of data in ways that would affect the quality of the content (lower resolution and less detailed textures, for instance).

There's a whole different cathegory as well which I'd like to mention here. Any knowledgeable member is free to correct me, but procedurally created content takes little space on the disc and long load times to create on the console memory. With Blu-ray, there's no need of these long loading times since these don't depend that much on the drive speed, but on the speed of the CPU to recreate the content procedurally. If the CPU doesn't have to waste time processing that, it becomes a win-win: a portion of the CPU horsepower can be used for other useful purposes and the loading times are shorter.

In any case, saying developers are lazy to perform compression, withouth delving in that subject at all, is a totally preposterous argument.

Crossbar
08-26-2006, 09:32 AM
There are a lot of benefits from compression.
Compressed textures saves system memory, you can keep more textures in RAM for fast access. It also helps cut load times when textures needs to fetched from disk, it helps cutting time when new levels need to be fetched.

I think VG is right that high quality audio and video takes lot of space and that data can also be streamed from disk when used, so that's probably where the blu-ray disk give most benefits.

archy121
08-26-2006, 09:43 AM
Just came across thins interesting opinion whilst browsing another forum



I just noticed that Dead Rising is 7.8GB. I think we're definitely approaching the DVD storage ceiling

Seems like there will be plenty more games with highest compression for XBOX360. Games are just reaching 2nd generation & they are hitting the ceiling already. Things may get very tight year or two down the road. Seems Microsoft may have made a mistake not including HDDVD instead of DVD.

Archy

woundingchaney
08-26-2006, 09:51 AM
Just came across thins interesting opinion whilst browsing another forum



Seems like there will be plenty more games with highest compression for XBOX360. Games are just reaching 2nd generation & they are hitting the ceiling already. Things may get very tight year or two down the road. Seems Microsoft may have made a mistake not including HDDVD instead of DVD.

Archy


For MS including HD DVD or BR would have been a potential catastrophy. I dont think that the whole DVD9 is as big of a concern as many would make it out to be but I dont doubt that it is a concern.

I fully expect MS to move to 2 disks probably by the end of the the next year, or at least they will be relatively common.

VG I believe your referring to procedural synthesis in which a program compiles objects randomly from a data base (of course the sets boundaries so an elephant doesnt appear in city or something LOL). This is being used a an upcoming game for the 360 called Just Cause, the game doesnt seem too impressive although the whole concept of procedural synthesis is intriguing - judging the tech on the game wouldnt be right either LOL.

http://www.wonderlandblog.com/wonderland/2006/01/procedural_synt.html

http://nintendo.about.com/library/procedural/blprocedural1.htm

Luis
08-26-2006, 09:59 AM
The main reason why MS uses DVD9 is simply because they didn't want to lose so much money on subsidized hardware sales. They probably wanted to keep costs low as well as not risking too much with new technology.

When I talked about procedurally created content, I talked about the concepts behind .kkrieger (http://en.wikipedia.org/wiki/.kkrieger):


The entire game uses only 97,280 bytes of disk space. Much of this small size is attributable to the game's use of procedurally generated content. In contrast, most popular first-person shooters fill one or more CDs or DVDs. Unreal Tournament 2004, for example, requires more than five gigabytes, which is more than 50,000 times the disk space in comparison. (It must be mentioned, however, that .kkrieger only contains one level.) According to the developers, .kkrieger itself would take up around 200-300MB space if it had been stored the conventional way.Some things can be done like this, but it requires a really long time to process, which I don't find practical in a commercial game. Anyway, .kkrieger is quite an extreme example.

These two generation processes explain the extensive loading time of the game - all assets of the gameplay are reproduced during the loading phase.

woundingchaney
08-26-2006, 10:02 AM
The main reason why MS uses DVD9 is simply because they didn't want to lose so much money on subsidized hardware sales. They probably wanted to keep costs low as well as not risking too much with new technology.
Pretty much what it comes down to and the fact that both formats stand a good chance at failure (although I would say HD DVD more so than BR). Also there wasnt an option of any HD optical format when MS launched.

Luis
08-26-2006, 10:06 AM
Pretty much what it comes down to and the fact that both formats stand a good chance at failure (although I would say HD DVD more so than BR). Also there wasnt an option of any HD optical format when MS launched.I always thought they should have waited one more year. I also hoped that Sony wouldn't have needed to release PS3 until mid-late 2007.

woundingchaney
08-26-2006, 10:07 AM
I always thought they should have waited one more year. I also hoped that Sony wouldn't have needed to release PS3 until mid-late 2007.
In all honesty Im really satisfied with the situation as it is. Sony came a little late and MS came a little early but everything seems to be working reasonably well for the consoles and the consumers.

2007 would have just been too long. IMO

woundingchaney
08-26-2006, 11:16 AM
The main reason why MS uses DVD9 is simply because they didn't want to lose so much money on subsidized hardware sales. They probably wanted to keep costs low as well as not risking too much with new technology.

When I talked about procedurally created content, I talked about the concepts behind .kkrieger (http://en.wikipedia.org/wiki/.kkrieger):

Some things can be done like this, but it requires a really long time to process, which I don't find practical in a commercial game. Anyway, .kkrieger is quite an extreme example.


What do you mean by process. Are you referring to the longer loading times, if content is generated on the fly why would it take longer to load????

If so I would agree that longer loading times would be a pain but think of all the advantages that this would bring, particularly in the dev. stages of the game. Although I only somewhat familiar with the concept and havent really looked into it.

Luis
08-26-2006, 11:30 AM
Instead of wasting CPU time on recreating content on the fly or dedicating long loading times for this purpose, I'd very much prefer having all the content directly available on the Blu-ray disc and stream it from the disc all the time with the help of the HDD as well, and saving CPU time and resources for other important things. Same would apply for heavily compressed content, even though this is not so easy to elaborate on. In any case, calling the developers "lazy" and assuming compression can do miracles is simply wrong.


People over on another fourm were dogin the Resistance team saying that the only reason the game was 22 gigs was because of them being to lazy to compress stuff.Plain ludicrous argument.

I'm no expert either, but I'm sure the space Blu-ray discs provide will be used by many developers in effective ways. It's something they can rely on and I'm sure they will take advantage of it. Besides of having more space for game content, they will always have space for nice extras: soundtracks, all voice acting in all languages in one disc, other games (think of Tekken 5 including Tekken 1, 2 and 3) making of documentaries (HD quality), generally higher quality audio and video and so on.

woundingchaney
08-26-2006, 11:34 AM
Instead of wasting CPU time on recreating content on the fly or dedicating long loading times for this purpose, I'd very much prefer having all the content directly available on the Blu-ray disc and stream it from the disc all the time with the help of the HDD as well, and saving CPU time and resources for other important things. Same would apply for heavily compressed content, even though this is not so easy to explain. In any case, calling the developers "lazy" and assuming compression can do miracles is simply wrong.

Plain ludicrous.

I'm no expert either, but I'm sure the space Blu-ray discs provide will be used by many developers in effective ways. It's something they can rely on and I'm sure they will take advantage of it.


Well it would depend on just how much cpu performance would be compromised, Im not thinking it would be very demanding for a cpu to randomly generate objects.

I wonder if the tech. would save on ram seeing as how specific objects wouldnt have to be placed at specific spots. But then again the procedure may require more ram as well.

Luis
08-26-2006, 11:38 AM
Well it would depend on just how much cpu performance would be compromised, Im not thinking it would be very demanding for a cpu to randomly generate objects.No, that's not what it is about. Go read that .kkrieger article and I suggest you to download it and execute it to get an idea of how troublesome it could become.

woundingchaney
08-26-2006, 11:41 AM
No, that's not what it is about. Go read that .kkrieger article and I suggest you to download it and execute it to get an idea of how troublesome it could become.
Which article??

Luis
08-26-2006, 11:45 AM
Which article??Didn't you see the link in my previous post about .kkrieger??? (http://forums.e-mpire.com/showpost.php?p=1210050&postcount=8)

woundingchaney
08-26-2006, 11:51 AM
The Wikipedia article???

Doesnt really give much info but this is rather interesting.


Textures are stored via their creation history instead of a per-pixel basis, thus only requiring the history data (possibly as low as ~300 bytes per texture at any resolution) and the generator code to be compiled into the executable, producing a relatively small file size.
Meshes are created from basic solids such as boxes and cylinders, which are then deformed to achieve the desired shape - essentially a special way of box modeling.


Sounds pretty intriguing Im sure there is a downside to everything though.

Luis
08-26-2006, 11:57 AM
Sounds pretty intriguing Im sure there is a downside to everything though.That's what I've been saying all the time...

woundingchaney
08-26-2006, 11:59 AM
That's what I've been saying all the time...
lol

Gotcha/understand

Crossbar
08-26-2006, 12:34 PM
Compression and procedural textures are not really the same thing.
krieger is a pathological example of procedural created content, where they wanted to achieve a certain goal (small footprint on the HD) and paid no attention to a lot of other aspects such as load times and memory usage.

I agree with Wounding that using decompressed content can often reduce load times as the CPU time it takes to decompress certain formats can be far less than than the time to load the same uncompressed data. All depending on how much CPU power you have to spare. The cell may very well use far more advanced compression format such as wavelet-compression (JPEG2000) than what is commonly used today.

S3TC is used by both 360 and PS3, you can read about it here.
http://en.wikipedia.org/wiki/S3_Texture_Compression

Some texture may even be decompressed each frame cycle they are used if that say something about how fast ST3C decompression is.

An other advantage with large storage is that it allows you to have the same texture stored with different quality and at different sizes, which give the programmer more flexibility.

woundingchaney
08-26-2006, 12:39 PM
I think one thing that is definetely not understood is that compression is not necessarily bad. Compression tech. has performance increases as well.

When we start talking about the need for devs to "overly" compress data to fit on a single dvd9 (as in instance with concerns revolving around the 360) then that would be an instance of a negative aspect of compression, but compression is not some evil sentient being.

Luis
08-26-2006, 12:44 PM
I agree with Wounding that using decompressed content can often reduce load times as the CPU time it takes to decompress certain formats can be far less than than the time to load the same uncompressed data. All depending on how much CPU power you have to spare.I think he wasn't the one who said that, LOL.

I did say that compression and procedurally generated content were not the same thing BTW.


When we start talking about the need for devs to "overly" compress data to fit on a single dvd9 (as in instance with concerns revolving around the 360) then that would be an instance of a negative aspect of compression, but compression is not some evil sentient being.Compression is not bad at all per se, but people who say that developers are too lazy to use compression are simply ignorant. They must believe compression works like a miracle, and it doesn't. If a game requires 22 GB to include all of its content, it's because of a number of good reasons. The whole "lazy developers that use no compression" argument is simply ludicrous and misinformed.

Crossbar
08-26-2006, 01:04 PM
I think he wasn't the one who said that, LOL.

I did say that compression and procedurally generated content were not the same thing BTW.
You are right Wounding said something different about CPU load.

I wanted to make a distinction between the original topic of compression and procedural synthesis. But they often occur in the same discussions, so it may not be much point in doing that.

I think we will see examples of procedural synthesis on both PS3 and 360 in the future, but they will benefit them both, but they will for example never replace the bulk of textures created by artists.

woundingchaney
08-26-2006, 01:14 PM
I didnt think that anyone thought that compression and procedural synthesis was the same thing. PS is more of a tech. that decreases the need for compression or alternative in some cases (this is kind of a bland statement I know).

woundingchaney
08-26-2006, 01:15 PM
Compression is not bad at all per se, but people who say that developers are too lazy to use compression are simply ignorant. They must believe compression works like a miracle, and it doesn't. If a game requires 22 GB to include all of its content, it's because of a number of good reasons. The whole "lazy developers that use no compression" argument is simply ludicrous and misinformed.


I agree although a 22 GB game could of course be reduced in size with the use of compression tech. I think the possibility of it being reduced to 7 GB is ridiculous.------ Without compromising quality that is.

section
08-26-2006, 01:49 PM
I agree although a 22 GB game could of course be reduced in size with the use of compression techDepends on the original data. If it comprises mostly of already compressed data, as games usually do, the shrinkage would be almost nonexistent.

woundingchaney
08-26-2006, 03:25 PM
Depends on the original data. If it comprises mostly of already compressed data, as games usually do, the shrinkage would be almost nonexistent.
Right, but I believe the scenario was of uncompressed data.

jaxmkii
08-26-2006, 07:38 PM
Just came across thins interesting opinion whilst browsing another forum



Seems like there will be plenty more games with highest compression for XBOX360. Games are just reaching 2nd generation & they are hitting the ceiling already. Things may get very tight year or two down the road. Seems Microsoft may have made a mistake not including HDDVD instead of DVD.

Archy
there own FSX is 14 gigs...:doh: so much for a 360 port

woundingchaney
08-26-2006, 07:40 PM
there own FSX is 14 gigs...:doh: so much for a 360 port
What is FSX???

Smokey
08-26-2006, 07:43 PM
is it a Flight Sim

woundingchaney
08-26-2006, 07:47 PM
A flight sim for the pc right. Why not multiple disks????


If anything the game would probably have to be coded specifically for the 360 but I dont know why it wouldnt work.

Smokey
08-26-2006, 07:49 PM
ive seen FSX mentioned a coupla times i was just assuming it was a Flight Sim because they were talking about the water effects in FSX



Quote:Originally Posted by saxdawg00
Hands down, THE best water effects I've ever seen anywhere, PC or console!

posted by jaxmkii
go look up DX10 version of FSX

masteratt
08-26-2006, 07:58 PM
FSX= Flight Simulator X
...obviously.

its the latest in MS's flight simulator series. the series always had outstanding graphics..in a simulation kind of way to show off the latest hardware.

Smokey
08-26-2006, 08:01 PM
FSX= Flight Simulator X
...obviously.
well no need to be a smart arse lol :)

masteratt
08-26-2006, 08:08 PM
lol well i didn't want to sound patronising ;)

Lekko
08-26-2006, 08:12 PM
Uh, one huge thing that seems pretty obvious to me: you still have to read the data to memory BEFORE you can uncompress it fully. Think about downloading a file off the internet. If it's compressed, it takes less time to download it, but more time afterward to decompress it. If it is uncompressed, it's the other way arround.

So to create a formula for solving this. (time to read compressed data off DVD) + (time it takes to decompress data or synthesize a leve) = load time.

vs.

(time it takes to read an uncompressed level) = load time.

All you number crunchers can work on it from here. It's going to be a fun math problem considering the different processors and drive speeds.

Crossbar
08-26-2006, 08:25 PM
Uh, one huge thing that seems pretty obvious to me: you still have to read the data to memory BEFORE you can uncompress it fully.
That is not true for all compression formats. There are some like Huffman encoding, (zip I think), etc. that you decompress on the fly.

woundingchaney
08-26-2006, 08:29 PM
Is anyone really familiar with MS compression formats as this seems to be the ol' DVD9 vs BR scenario??

Smokey
08-26-2006, 08:32 PM
DVD9 vs BR scenario
it is, hidden in another form :)

cpiasminc
08-26-2006, 10:02 PM
Are there any benifits to compressing things (textures, audio, ect.) in a game?
All games have compressed audio and textures these days. PS2 was the last of the uncompressed audio/texture platforms, and that was mainly because there was little to no compressed formats supported in hardware (quantized texture formats were there, which is what everybody used, but that's rather different from "compression"). Even the PSP supports quite a number more. Similar was the case with audio on the PS2 because timing resolutions and synchronicity of races are very, very sensitive on a good PS2 engine -- certainly a crappy one wouldn't be too troubled, though (which is something of a paradox).


People over on another fourm were dogin the Resistance team saying that the only reason the game was 22 gigs was because of them being to lazy to compress stuff.
I'm fairly sure it has more to do with being in a development state. There are surely a number of test sets and ancillary data along with stuff that has nothing to do with the actual game itself. For instance, the game itself may only really be about 8 GB, while there's other junk either not meant to go into the game or meant to serve as "bonuses" that are filling up the disc. It should also be noted that with optical discs it doesn't hurt to have duplicate data in order to save seek times. No one ever really said that the actual net in-game content is 22 GB.


From what I understand, it is better to have un - compressed data than compressed for the simple fact that it takes CPU time to 'unpack' such compressed textures.....
Nope. Quite the opposite. Most compressed formats that are used in game are very simple varieties of compression -- simple enough that the time you save by reading less data off the disc is many thousand times greater than the time to decompress. Most all games (certainly all console games) also archive their data into large packages (similar to .ZIP files) so that they only have to take the OS file system hit once -- this alone brings load times down by a factor of about 4:1 on most machines, even without compression. On PCs, when you've installed to a hard drive, the difference is much smaller, but on consoles reading from an optical disc which a little over ten times slower than a hard drive with over 20x slower seek time, the difference is pretty large.

Compressed textures are a complete non-issue. They're never decompressed. Any modern GPU will read the textures in various (though specific) compressed formats (and again, it's faster to do this than use uncompressed -- except sometimes on the PSP), meaning the textures remain in memory compressed all the time. For instance, Crossbar's example of JPEG2000 certainly won't be used for textures at all because the GPU doesn't natively support it. And trying to shaderize the decompression is asking for trouble.

Audio is another thing where decompression costs you some CPU cycles, but memory is so so far behind the CPU these days that moving less data around is almost always a win, and you only really have to decompress a small few frames of audio at a time. Again, it's generally a net win. Things like quick sound effects which demand low latency are often not going to be compressed. Long dialogue exchanges and music almost certainly will be in all games.

woundingchaney
08-26-2006, 10:31 PM
Well I just learned a lot.

Hrama
08-26-2006, 10:36 PM
Indeed, so did I. Thanks a lot Cp, that was an excellent explanation on how compression/decompression can work. (And I actually understood it all for once!)

Crossbar
08-27-2006, 02:31 AM
For instance, Crossbar's example of JPEG2000 certainly won't be used for textures at all because the GPU doesn't natively support it. And trying to shaderize the decompression is asking for trouble.

I never said the GPU would handle wavelet decompression, I explicitly said that the Cell may do that.

All depending on how much CPU power you have to spare. The Cell may very well use far more advanced compression format such as wavelet-compression (JPEG2000) than what is commonly used today.
How this may be implemented I leave to the code magicians at Polyphony Digital and other Sony studios. :worthy: I am sure they will use the SPEs very efficiently within a couple of years and decompression will be one way to use them. :)

LaLiLuLeLo
08-27-2006, 02:48 AM
Cpiasminc, you don't know how much I (WE) appreciate having someone around who knows what he's talking about.

for serious.

Garfunkel
08-27-2006, 03:03 AM
thanks for that cpi.

cpiasminc
08-27-2006, 05:58 AM
I never said the GPU would handle wavelet decompression, I explicitly said that the Cell may do that.
What I was trying to say is that's exactly the problem. If the GPU can't do it, it doesn't really buy you anything except maybe some shrunken load times. It means that the texture will either have to be decompressed in memory (thereby using more RAM space and more bandwidth), or it has to be decoded in shaderworld.

You don't quite get the luxury of linear access cycles that audio inherently has (by nature of being 1-dimensional data), so you can't packetize the decompression. Random access patterns are part of the nature of texture reads, so you basically have to decompress manually at some point. And wavelets is a bit much to put on shader code which equals uncompressed textures in memory which take just as many cache reloads as if you never compressed the texture in the first place.

Compare that to an S3TC/DXT texture which will give you 4:1 or 8:1 and can remain compressed all the time, and the GPU natively supports it. The DXT texture wins on everything except image quality.

In the case of IBM's TRE demo, the reason they used MJPEG was to buffer off a few frames of animation ahead so that the whole thing would run smoothly irrespective of localized variations in real performance.

yoshaw
08-27-2006, 06:07 AM
For instance, the game itself may only really be about 8 GB, while there's other junk either not meant to go into the game or meant to serve as "bonuses" that are filling up the disc. It should also be noted that with optical discs it doesn't hurt to have duplicate data in order to save seek times. No one ever really said that the actual net in-game content is 22 GB.

That is an interesting perspective CPI. I have a question though. Would you(or the team of devs you're working with) be willing to share future title demos in playable or video form whilst provided the space of Bluray?

Because I was wondering maybe one of the things Insomniac is doing is, like you said, lots of bonus content. Including developer commentary, making of featurettes and most probably a look into Insmoniac's past achievements(in form of a documentary) etc. Ofcourse not to mention, a sneak peak at Ratchet & Clank PS3, probably a playable demo?!

Danji
08-27-2006, 06:17 AM
The main reason why MS uses DVD9 is simply because they didn't want to lose so much money on subsidized hardware sales. They probably wanted to keep costs low as well as not risking too much with new technology.

When I talked about procedurally created content, I talked about the concepts behind .kkrieger (http://en.wikipedia.org/wiki/.kkrieger):

Some things can be done like this, but it requires a really long time to process, which I don't find practical in a commercial game. Anyway, .kkrieger is quite an extreme example.
Something that you have to take into account is that (CPI has said this before) .KKrieger leaves a 300MB+ footprint in the memory which is horribly impractical for console development. That's ignoring the fact the game looks like crap and does that...imagine if it had profound graphics. It would take up an exponentially larger amount of space!

Crossbar
08-27-2006, 06:23 AM
What I was trying to say is that's exactly the problem. If the GPU can't do it, it doesn't really buy you anything except maybe some shrunken load times. It means that the texture will either have to be decompressed in memory (thereby using more RAM space and more bandwidth), or it has to be decoded in shaderworld.

Yeah, plenty usage of S3TC is a no-brainer, but there is supposed to be a big texture cache on the RSX and there is plenty of bandwidth between Cell and the RSX. I think we will see alternative solutions in the future, that avoids the kind of drawbacks you mention. It may take a few years, but I think we will see some really clever usage of Cell. :)

makeitlookreal
08-27-2006, 06:24 AM
CPI,

We really appreciate all of the information.

Lets also remember that CPI has told us that the RSX does not support any exotic types of compressed textures. It basically uses the same types that the 360's GPU supports.

Basically, compression in the PS3 is pretty much going to be the same as in the 360.

EDIT: If there were large texture caches on a system could they be used for something more than just covering up latency or reducing misses? When it comes to texturing would a large texture cache potentially be useful in another way?

cpiasminc
08-27-2006, 06:30 AM
That is an interesting perspective CPI. I have a question though. Would you(or the team of devs you're working with) be willing to share future title demos in playable or video form whilst provided the space of Bluray?

Because I was wondering maybe one of the things Insomniac is doing is, like you said, lots of bonus content. Including developer commentary, making of featurettes and most probably a look into Insmoniac's past achievements(in form of a documentary) etc. Ofcourse not to mention, a sneak peak at Ratchet & Clank PS3, probably a playable demo?!
Very conceivably possible -- in the case of studios like Insomniac or Naughty Dog, they're rather small to be having widely offset multiple projects at once in order to be able to demo their own yet-to-be work on their own discs... but being owned by a larger company means demos get spread around. For instance, God of War 3 and a next-gen Jak game, for instance would be made at sister studios which are a half-hour walk apart from each other.


If there were large texture caches on a system could they be used for something more than just covering up latency or reducing misses? When it comes to texturing would a large texture cache potentially be useful in another way?
Well, they're not really programmable or anything -- the function of the texture caches is basically fixed. Using on-die SRAM itself for purposes other than a texture cache is not really up to anyone but the hardware designers. And of course, it's possible to throw in, at some point in the future, better speculative fetching, which will improve net hit/miss rates without relying on size. If you see some other benefit out of texture caches than their native purpose, I can only really attribute that to sheer coincidence.