The Deadly Sins of Texturing

[ChinRey]

I'm feeling a bit evil today so I decided to start working on a list of the Seven Deadly Sins of Texturing. I've done 15 of them so far:

1. Repeat inflation
2. Resolution inflation
3. Colour inflation
4. Excessive resolution
5. Monochrome textures
6. Quasi-baking
7. Empy UV maps
8. Multiple copies of the same texture
9. Mirrored textures
10. Hidden textures
11. Uneven texel density
12. Atlas abuse
13. Rougue alphas
14. Custom full transparency/blank textures
15. Noisy emptiness

More details on my blog. All kinds of feedback is welcome.

Edited February 21, 2019 by ChinRey
Typo

[Frenchbloke Vanmoer]

can I add

Still using the Half Life 2 game rip textures from 10 + years ago on builds
Scale - this falls under texel density but is an annoyance of mine regarding bricks and objects that cannot be larger than their RL equivalents
Shiny everything.  
 

 

[Frenchbloke Vanmoer]

also - no mod on "accidental" shiny things
like this, from a well known gentleman's outfitter
Behold - shiny wool
or maybe it's wet ? 
Varnish ? 

https://gyazo.com/e818d993ca7ad1b9093db37d81e233f0

Edited February 21, 2019 by Frenchbloke Vanmoer

[ChinRey]

41 minutes ago, Frenchbloke Vanmoer said:

Shiny everything.

And fullbright everything of course.

But this is a list of Deadly sins and that's a bit more serious than gross mistakes and poor judgement. To make it to the list, it has to be something so obivously wrong that nobody in their right mind could come up with a plausible explanation why it's a good idea. I'm not even sure if uneven texel density should be on the list.

It's the same with scale. What exactly is correct scale in Second Life wher everything is out of proportion with everything else?

Essentially, although I won't isnsist on it, it seems that to make it to the list, it'll have to be something that adds to the lag but does not contribute anything whatsoever to the actual visuals.

 

41 minutes ago, Frenchbloke Vanmoer said:

Still using the Half Life 2 game rip textures from 10 + years ago on builds

I do understand why old-timers who used to see them everywhere are tired of them and I still don't know the legal aspects (although I do notice that one of the biggest and oldest texture brands in SL - and one who ahs taken a very firm stand against IP violation - still sells some of them).

But from a purely technical point of view they are some of the best textures SL has ever seen. They are fairly low resolution but still amazingly lively and full of details and they are very flexible. The reason why they were used so much for a while is that they're so good.

I do agree they may not be the textures we want for the two reasons I mentioned but they are certainly the kind of textures we need more of in SL.

Edited February 21, 2019 by ChinRey

[ChinRey]

32 minutes ago, Frenchbloke Vanmoer said:

like this, from a well known gentleman's outfitter
Behold - shiny wool
or maybe it's wet ? 
Varnish ?

Oh. I think poor use of normal and specular maps is worth an article of its own.

[Frenchbloke Vanmoer]

some genius came up with the notion that using a lower resolution materials layers than the original texture  - he alone deserves an article. That was not a pretty sandbox, I can tell you

Impossible to match baked in sunlight and shadows has to be included surely ?

visible seams

 

[Frenchbloke Vanmoer]

I just remembered I had this. 
A really nice full perm porthole that is literally impossible to make look as if it came from this decade, texture-wise. 
 

[Kyrah Abattoir]

On 2/21/2019 at 7:45 PM, Frenchbloke Vanmoer said:

some genius came up with the notion that using a lower resolution materials layers than the original texture  - he alone deserves an article. That was not a pretty sandbox, I can tell you

Care to explain?

Edited February 25, 2019 by Kyrah Abattoir

[Frenchbloke Vanmoer]

When materials first appeared I was in the Caledon sandbox. There was concern that using three textures on 1 was the work of the devil so it was suggested that to make it less of a resource hog why not make the normals and spec layers smaller. 

Picture the scene, a 1024 diffuse brick wall with some cracks. Then the materials that were 512.  It wasn't pretty 

[Ana Stubbs]

1 hour ago, Frenchbloke Vanmoer said:

When materials first appeared I was in the Caledon sandbox. There was concern that using three textures on 1 was the work of the devil so it was suggested that to make it less of a resource hog why not make the normals and spec layers smaller. 

Picture the scene, a 1024 diffuse brick wall with some cracks. Then the materials that were 512.  It wasn't pretty 

To counter, I have some very nice leaded windows where the normal map and spec maps are a tiling 64x64, (because each light does not differ that much) and the diffuse is a 512x512 to add more visual variation.

[arton Rotaru]

2 hours ago, Frenchbloke Vanmoer said:

Picture the scene, a 1024 diffuse brick wall with some cracks. Then the materials that were 512.  It wasn't pretty 

Using different sizes of the various map types is common practice actually. There is nothing wrong with that. It's certainly not a general rule to use it on everything. Indeed, it depends on the particular model if you can get away with it, or not. 

Depending on which map holds a lot of detail, you can even have the diffuse smaller than the normal. 

My spec maps are almost always smaller than the two other maps. Does it show in direct comparison? Most likely yes. But the differences aren't significant enough to justify a larger map in a lot of cases. 

 

[Kyrah Abattoir]

3 hours ago, Frenchbloke Vanmoer said:

When materials first appeared I was in the Caledon sandbox. There was concern that using three textures on 1 was the work of the devil so it was suggested that to make it less of a resource hog why not make the normals and spec layers smaller. 

Picture the scene, a 1024 diffuse brick wall with some cracks. Then the materials that were 512.  It wasn't pretty 

No that's stupid, and I've seen you spout this nonsense multiple times now. There is no "be all end all" rule for this.

• Very often you can get away with fairly small specular maps because specularity tend to be the more "subtle" part of the material and unless you have an object composed of many different metals, plastics, fabrics etc, you won't see the difference.
• How big your normal map needs to be directly relates to how much data it is carrying, i typically render my normal maps in 4K and then bring them down to the smallest size i can get away with and still get the detail/smoothness I want, try different reduction algorythms, some will give you a better result than others for a given map.
• Diffuse, again, it depends how much data your diffuse map is carrying. If you're trying to cater to both ALM and non ALM users, then you will most likely have to use a large diffuse. For ALM, the question is how much "more" color data (or transparency data in some cases) do you need once the normal and specular map have done their job.

 

This technically isn't an "uneven texel density" sin because we are talking about some maps being maybe half, or a quarter smaller, not density changes of a factor of 10.

Edited February 25, 2019 by Kyrah Abattoir

[Kyrah Abattoir]

Here is an addition to the deadly sins of texturing: Bake all the thing!

Right now i'm looking at a box of cookies:

• It contains 5 cookies: each cookie is uniquely textured despite being pretty much identical (recycling?)
• The box is covered in a cute little print. Initially i thought it was a repeating pattern, but on close inspection, the creator felt that they HAD to burn lighting into it, so that's a unique texture for what is essentiallty provided by the engine already (and if you really wanted a light & dark side, you could just have used 2 faces and a tint).

The result is that despite the object using a whole 1024x1024 texture, most of it is basically wasted, half the shading of the box is spent under a wrapper and can't be seen.

Edited April 6, 2019 by Kyrah Abattoir

[animats]

The viewer could handle oversized textures more effectively. The textures are stored in a progressive JPEG 2000 format. If the viewer only wants 128x128, it can just read the first part of the file. It tries, but the texture loading policy isn't that great. LL has been making noises about Project Arctan to address that.

The basic idea is that you want to equalize the number of texture pixels (texels) per screen pixel across the field of view. If something occupies only 100 screen pixels, then you only need a 16x16 texture for it.

[ChinRey]

5 hours ago, Kyrah Abattoir said:

Here is an addition to the deadly sins of texturing: Bake all the thing!

That's no. 6 on the list - the "quasi-baking". Maybe I should have made it a bit clearer but I do not want to give the impression that baked textures are inherently bad. Bake when it really adds significantly to the overall looks but use modern tileable and/or reusable textures wherever possible.

This reminds me of something that happened to me recently. I've been giving some advice to a new, young and very talented content creator and last week he showed me an absolutely wonderful house he had made. After the usual advice on LoD and physcis models, we talked a bit of the texturing. He was using unique baked 1024s for each and every outer wall of the house and told me that was the only way to get good details.

So, I rezzed a copy of Hattie Panacek's old prim chapel. Hold on, I think I have a picture of that building somewhere...

Ah! here it is in the background. It's not the best picture I have of it but it should do:

Anyways... I told him how all the outer walls of the chapel was textured with a single 512. In RL he lives about 2,000 km away from me but I could still hear the thump as he fell off his chair.

This wasn't fair of course. Hattie is one of SL's ultimate masters of texturing - comparable even to Oriolus Oliva and Crazy Mole at their best - and very few people have enough texturing talent to match those guys. But we can all learn and improve and I do hope the list of Deadly Sins will help. But remember, it's not a complete guide to great texturing, there's not room for that in a single blog article. It's only a list of the very worst mistakespeople make.

Edited April 6, 2019 by ChinRey