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View Full Version : A few questions on production quality textures


Stradigos
08-19-2011, 07:27 AM
1) Obviously there's no standard texture resolution size and you should use which ever resolution gives you the best results. Having said that, does an 8k x 8k texture sound obscene for production quality renders? 8k doesn't look too bad at the distance those images below are at, but when I bring the camera closer, things start to crap out pretty fast. Unfortunately, do to the nature of the animations, I need to bring the camera fairly close to the model. I'm thinking about going even larger, but... question two!

2) Holy shit Maya slows to a crawl when I'm using big textures. I don't understand why having a large texture connected to a material slows the attribute editor to the point where it takes 15 seconds to change a single value. And don't get me started on the Hypershade... the thing is practically unusable. Maya 2010 didn't seem to have this problem to bad, but Maya 2012 is another story. I'm on a high end workstation with 16GB of RAM FFS! It probably doesn't help Photoshop is running in the background hogging 5.2 GB of memory =P

Any tips for increasing Maya's texture resolution? I mean, resolution is what it is... I noticed a huge jump in quality when I actually had high quality images to work with (Uh, 3dsk is awesome). But now I'm just trying to get the most bang for my buck bringing those into Maya.

EDIT:

I guess too that I could use several smaller resolution textures on the object. I hadn't thought of that.

Giometric
08-19-2011, 09:13 AM
I've seen 8k textures used in production stuff before, but what does your UV layout look like? If your textures are still blurry at that size it may be a matter of packing your UVs more efficiently. If the issue is more that you have to get really really close (at the distances in your attached pics he looks fine btw, maybe needs a bit of bump but I'm assuming it's not finished yet), then what you might do instead of increasing texture size, is blend in some procedural noise textures to kind of fake in some detail at really close distances, for both diffuse and bump.

As for the performance problem, that is sort of strange.. I mean 8k is big but video cards have been more than capable of displaying them for a long time now, it should not be choking on just one 8k texture. You wouldn't happen to have an ATI video card would you? If you do, try swapping in an NVidia card if possible and see if it gets better, if not just try updating video drivers and see if that helps. Actually either way try updating (or maybe downgrading!) video card drivers and see if anything changes.

Stradigos
08-19-2011, 11:09 AM
See attached.

I'll try getting the IT guys to update the Nvidia graphic drivers next week. Perhaps that's the issue. I'm also going to do that multiple UV map trick and use several 4k textures instead of one big one.

malcolm
08-19-2011, 11:27 AM
Is this for film or games? 8192x8192 seems pretty huge and I would imagine Maya would die with the texture that big in the viewport/hypershade. You could probably use a 2048x2048 for the head and 4096x4096 for the body. In the current uv layout it looks like more than half the texture resolution is wasted in black space. I'd check out some unwraps posted by artists here on the forum and use that as a base. You could also investigate using a detail map for your close up shots. I'm curious, what this guy uses for texture resolutions and how many textures he uses. I e-mailed him and asked, but he never responded.

http://www.eklettica.com/index.html

Stradigos
08-19-2011, 12:46 PM
This is for film. I just found a script to turn off refreshing the thumbs in the Hypershade. It seems to have helped a little, at least.

renderThumbnailUpdate false;Do I use multiple materials then for the character since I have multiple UV sets now? One for head, one for body? I see I can use the relationship editor to define which UV sets are used in one map slots, but seeing as I can't use multiple textures for color (for example), I'm not seeing another way to have two diffuses, two normals, etc. for the same model. Is this correct?

And wow... yeah, I would like to know that too.

What do you mean by detail map? A quick search didn't produce much besides normal map information.

Giometric
08-19-2011, 01:22 PM
Yeah it's pretty much the same idea as a detail normal map. You have a bump/normal map that tiles very small on the model so you only really see it from up close, it helps alleviate the blurriness from getting too close to the main texture. For a bump map you could use a Mix2Colors node and multiply it on top of your regular bump map or something.

As for the UV set thing, as far as I know yes, unfortunately you're going to have to use multiple materials now. I'm not completely positive on this, but you might be able to hook up at color/numerical values in the three copies up through expressions so that you only have to edit one and have that propagate out through the rest of them (except for the textures of course). There is also the possibility that simply using Mix2Color nodes to mix the maps together (making sure to assign each one their respective UV set) will also work. This would be way better since you'd have only one material so try this first actually.

Er, just remembered by the way that Mix2Colors probably still only works if you're rendering with Mental Ray. Don't know if there's a mixer node that works with Maya Software, there should be though.

Another thing I just remembered you can do is limit the max displayed viewport texture size in the preferences. You could probably tell it to limit the display of the 8k texture to only 4k or 2k in viewports, to see if it's really the video card choking on the 8k texture or Maya being dumb (aka Maya being Maya :) ).

Quack!
08-19-2011, 01:26 PM
At 8k by 8k you should be able to achieve a few pixels per PORE, if not more. That is a huge size and even with your current layout would seem to be fine for production. Maybe it is your source material that does not have enough definition. Paint a 1 pixel dot on the cheek of your texture and then view it in the render to see how tiny of detail you can achieve.

odium
08-19-2011, 04:40 PM
Yeah but thats 8k for a poorly unwrapped pelt map... Its not gonna fly. He's wasting like, 60% of his canvas.

With proper unwrap work, you could get the exact same level fo detail on a 2kx2k map.

Stradigos
08-19-2011, 04:47 PM
Yeah, good point. It seems to always be coming back to that. Thanks for the ideas guys. I'll hit the wiki and some unwrap threads and see if I can't get more out of my UV map first before I try anything else. Can't wait to post this in the P&P board with a full write up! :)

malcolm
08-19-2011, 09:54 PM
Yeah sure you could use multiple materials/shader balls for each part of the body that needed a separate texture then you wouldn't have to mess around with uv linking. Using multiple materials is pretty common on characters for games.

EarthQuake
08-20-2011, 01:21 PM
Yeah but thats 8k for a poorly unwrapped pelt map... Its not gonna fly. He's wasting like, 60% of his canvas.

With proper unwrap work, you could get the exact same level fo detail on a 2kx2k map.

You realize that 50% of an 8K is just 4x8k right? a 2k map is 1/16th the resolution of a 8k. So technically, no, you couldn't.

Now if he's just got a blurry mess with no real detail on a texture that large, then yes, but basics math tells you 2x2k doesn't = half of 8x8k.

Visceral
08-20-2011, 01:33 PM
Ok im not really 100% sure for this. But i imagine that you usually dont use alot of thoose textures for big productions. I mean some textures could be used but most of the magic comes from complex shaders and post process work. Textures could still be used but the shaders would play the major role.

Obviously im talking out of my ass and anyone should correct me.

EDIT: Also i notcied that your stubble is a part of your diffuse map, this would rarely be the case since you tend to create unique textures for that or simulate it using hair/fur

malcolm
08-20-2011, 01:52 PM
I have some more info on the issue after speaking with a friend who does character contract work for prerendered game trailers/intro movies.

4096x4096 for the head.
4096x4096 for the body.
4096x4096 for the hands.
4096x4096 for the feet.
4096x4096 for each piece of unique clothing.

And the uv mapping is the same as game industry uv mapping.

r_fletch_r
08-20-2011, 02:20 PM
Ok im not really 100% sure for this. But i imagine that you usually dont use alot of thoose textures for big productions. I mean some textures could be used but most of the magic comes from complex shaders and post process work. Textures could still be used but the shaders would play the major role.

Obviously im talking out of my ass and anyone should correct me.

EDIT: Also i notcied that your stubble is a part of your diffuse map, this would rarely be the case since you tend to create unique textures for that or simulate it using hair/fur

complex shaders generally do the job of calculating how the objects surface interacts with the shots lights. you still need textures to describe the surfaces. (I have no film experience but I've done rendering for TV using mentalray)

odium
08-20-2011, 06:03 PM
You realize that 50% of an 8K is just 4x8k right? a 2k map is 1/16th the resolution of a 8k. So technically, no, you couldn't.

Now if he's just got a blurry mess with no real detail on a texture that large, then yes, but basics math tells you 2x2k doesn't = half of 8x8k.

Oh you.... It was just a generalization, lol. Hes wasting a lot of space he could fill up, is what I mean :p

onionhead_o
08-22-2011, 09:12 AM
If this is for films, you could separate by type of materials for ex. head and body
one shader with uvlinking. so its easier to tweak instead of tweaking 2 shaders for the skin. You could even use a blend material as you main shader that holds all the other shader(cloth,skin,eye,hair..etc) thats how I did it when i was working at a vfx studio.

Stradigos
08-23-2011, 05:17 AM
Wow, thanks again for the great info guys. I ended up redoing the UV's to allow for the map setup Malcom mentioned and to improve the texture space. I keep forgetting too that I don't need to work in x^2 sizes for production work. Again, I'll post it up in P&P with a write up when it's done. :)

Visceral, yeah, definitely going to take out the stubble soon. I was too excited to see how things would turn out =]

vargatom
08-23-2011, 05:54 AM
We use multiple layouts for each character, 2k - 4k texture sizes. Most apps have serious trouble dealing with anything bigger than 4k, so it's always better to break it apart. Can cause some workflow problems with Zbrush but there's the multi displacement plugin to work around it...

And it's still more practical to use square textures, UV editors and such are all optimized for even proportions.