Differences between PS2 and GC hardware?

[marconelly!]

However, they do show off the limitations of CLUT compression somewhat well.

I am not aware there is any speciffic color intensity limitation with CLUT. It's basically reducing the number of colors in the texture to 16 or 256. Here are some very colorful and lively looking pictures with less than 256 unique colors:

Now imagine how easy is it to make, say, grass texture, or brick wall using 256 colors when it's possible to make such complex looking and colorful images with the same amount of colors.

 

[randycat99]

...and before people start picking those pix apart, mind you will be viewing those images on a comparatively color imprecise TV tube, not a computer monitor, and the images will be in motion. So any artifacts you care to pick out will be even less apparent under such conditions. Just note that one can certainly achieve a decent image that has more than "brown and green".

 

[marconelly!]

Most of those pictures, except for the last few have no more than 128 unique colors, actually, and they are used to display the whole scene, with variety of different colors. With textures, you can even break image into smaller parts and use different 256 colors in each part, and more often than not, your texture will not be used to present something so complex looking as the whole scene presented in these pictures. (remember, you will be rendering such scene in 16 or 32 bit from many small elements that use less colors)

 

[Tahir2]

Some of those pics are gorgeous..

 

[randycat99]

With textures, you can even break image into smaller parts and use different 256 colors in each part, and more often than not, your texture will not be used to present something so complex looking as the whole scene presented in these pictures.

That part I didn't know about. Is that really true? Having textures with different CLUTs in the same scene pretty much makes the color limitation issue trivial, doesn't it?

 

[Tagrineth]

Hmm. Wow. OK so I underestimated CLUT texturing a little...

I don't think anyone can deny how limited 4-bit CLUT is though.

So why IS it that, on average, PS2 games just don't have great textures compared to XB/GC?

 

[randycat99]

The short answer could be that your assertion is a myth in the first place.

The alternate answer is it comes down to the skill in implementing the artwork. Maybe developers just aren't accustomed to really exploring the limits of CLUT capabilities.

 

[Tahir2]

I just remembered I had one of those pics you posted marconelly ...

The one with the whales ... this was back when I was running Win98SE.

Where did you get them from??

 

[marconelly!]

I don't think anyone can deny how limited 4-bit CLUT is though.

You would be *very* surprised what is possible to make using just 16 colors. Especially when you don't need variety of different hues in one image (and for textures, that's more often than not exactly the case)

Some examples of 16 color images:

And 32 colors:

So why IS it that, on average, PS2 games just don't have great textures compared to XB/GC?

Most games developed exclusively for PS2 by talented developers have more than adequate texturing IMO. Sure, majority of games are sloppily made, quick cash-ins, but if you don't constitute good texturing just as being very colorful and vibrant, there are plenty PS2 games that fit the bill (it's hard to deny that BGA or SH2 have very good textures, althought they may not be colorful).

The one with the whales ... this was back when I was running Win98SE.

They are all made by several pixel artists from the computer demo scene. I grabbed these from www.gfxzone.org

 

[Tagrineth]

Well yeah, those pictures in 16 colours do look pretty good, but they're again kinda drab and monochromatic.

I don't base texture quality solely on colour variance, but it does help spice up visuals a bit.

When everything looks like the same dreary colours over and over and over and over and over, even in different environs, things can get pretty dull... great example of this would be Hybrid Heaven on N64. The overall texturing is VERY good (not counting Diaz's clothes ::shudder:: ), but everything's the same old grays.. the only variety is in a few very noteworthy bits.

I wonder, can a single CLUT texture use multiple lookup tables for different palettes? I'll be surprised if they can't... that'd probably get good results in the hands of a competent artist.

 

[marconelly!]

Sure, they look quite monochromatic, but that is what 4 bit textures are used for - adding some geometric looking details to a surface and such.

There are plenty of good looking brick, grass, etc textures in 16 colors. I've seen them someplace but completely forgot where.

 

[Tahir2]

Way OT but even more impressive
One of the pics above has a hidden message!

 

[marconelly!]

Oh yes, it's not so uncommon for the author to hide messages in these images Sometimes you have to change the pallette to reveal them.

 

[aaaaa00]

The question is not if you can make great art with CLUT8 and CLUT4 textures -- good artists will be able to work around the limitations of the medium -- the question is how long it takes, and how much effort you expend and how many artists you have to have to do it.

If it takes an artist five times longer to make a texture because he has to optimize it by hand for CLUT4 or CLUT8 pixel by pixel (as is done in that demoscene pixel art), it is not practical for use in a production environment -- especially as level design becomes more complex and the sheer amount of content you need to have to populate a modern game level grows exponentially.

 

[Fafalada]

Hmm. Wow. OK so I underestimated CLUT texturing a little...

It's not so much underestimating as it's looking at it from completely wrong perspective. The images Marc showed are just that - single image at a time. In a game, you have hundreds of texture images on screen at the same time, each able to have a completely unique palette of 16/256 colors.
Assuming "repetition of color is due to clut" is one of the most absurd misconceptions people I've heard on the web. It just doesn't make any sense whatsoever.

Moreover, what you assumed is complete opposite of how it works in real world - colorfull cartoony looking games are pretty much the Best fit for clut texturing.
The maps used in such art styles are low on color gradients, and high on color contrast and transition - which is exactly what clut compression is best used at (particularly 4bit).
Photographic textures with long color gradients is where Clut is at its worst, particularly low color key "drab" looking stuff tends to make perceptual errors the most noticeable

And yes, you can reuse the same map with different Cluts, which could potentially be a nice compression. Although this is again something that I could easily see working in a cartoony game, but not so much elsewhere.

 

[DemoCoder]

Implied lesbian eroticism looks good no matter how many colors used.

 

[randycat99]

If it takes an artist five times longer to make a texture...

Yes, now it takes an artist 5x as long and a team of them to pull this off... Maybe it takes a single artist 30 secs to click an autopallette button, examine the results, and custom tweak the pallette a bit?

You'd think all the Xbox developers threw up their hands in retreat when they found out you had to actually piece together some shader assembly code to use the "higher functions" in the XGPU. Everything requires some amount of expertise for good results.

 

[marconelly!]

The images Marc showed are just that - single image at a time. In a game, you have hundreds of texture images on screen at the same time, each able to have a completely unique palette of 16/256 colors.

Yes, I made sure to point that out. That really seems to be a common misconception.

 

[aaaaa00]

If it takes an artist five times longer to make a texture...

Yes, now it takes an artist 5x as long and a team of them to pull this off... Maybe it takes a single artist 30 secs to click an autopallette button, examine the results, and custom tweak the pallette a bit?

I don't think an autopallette function will give results as nice as that pixel art.

My point is that you can't expect artists to apply the same level of quality for every texture in the game as demonstrated by the pixel art Marconelly posted.

If it's much easier just to use 24-bit source art, then crunch it using JPG or S3TC for similar results, then you should go ahead and do that instead.

 

[Fafalada]

I don't think an autopallette function will give results as nice as that pixel art.

I'd show you what our quantizer does if I had some web space to upload to. (multimania appears to be down )

Besides, 2x2VQ tends to generate more color errors then Clut8 and people still generally used the autocompression with it - rarely if ever you need to handtune those.
4bit Clut is different, thogh people still just use it with automatic conversion more often then not - which does sometimes result in poor looking stuff.