Suggestions on materials implementation in SL

[Maxwell Graf]

"...They say materials are fair. ‘Tis a truth, I can bear them witness. And good to have—’tis so, I cannot reprove it. And useful, but for SL. By my troth, it is no addition to their function—nor no great argument of the lack of it, for we will be horribly in love with them."

-Shakespeare, from Much ado about nothing (kinda)

After having experimented with the materials viewers - both the beta and the latest release clients - I wanted to post some thoughts and offer a few considerations.

First, they add to the capabilities of designers in here, which is not a bad thing. Obviously, the fashion industry will be at the forefront and pushing it forward into the spotlight of mass-adoption by the residents and other markets. This is one of the wonderful consequences of such a dominant element in SL. You will most likely see it first on some article of clothing well ahead of ever seeing it on a house, chair or plant.

Yes, they will improve the look of things, or at least make things look different than they do now, much like sculpties and mesh did in their time. We will look back sometime in the future from an SL which looks perhaps vastly different than it does now. Things will be bumpier and shinier, if not more realistic.

To be clear (and this is critical to understand):
Normal and Specular mapping was implemented as a way to render low polygon objects inside an environment in such a way that they appear to have much more surface detail than they actually do, in order to enhance the visual while maintaining and encouraging the efficiency of the models.

One of the ways I would like to see materials improved deals with the lack of ability to adjust them once uploaded. Specular mapping has a variety of very cool ways in which it can be adjusted, particularly in regards to how it can also work with transparency. Normal maps do not adjust at all, though. Once applied, they are on or off. This is problematic.

In the process of creating material maps, one of the key aspects is understanding and being able to see how they will work within a particular rendering engine under varying conditions. Granted, a specific amount of resulting quality can be expected when created properly. When uploaded and applied to a model in an environment, however, the results can often be different than expected. Different rendering engines produce very different results. The results you see in your normal map creation application look very different once uploaded and applied in world. What will work in one will often not work as well in another and must be adjusted and tweaked. In fact, the final results may often depend on that ability to tweak inside the environment. While working inside both Bluemars, which used the CryEngine, and now Cloud Party, which uses OpenGL, the specific look of materials on items I made often came about precisely because I spent time messing with the settings, not something I could have predetermined.

This problem facilitates the need to make adjustments, the ability to increase or decrease the level of the specular AND/OR normal map effect in order to get the desired result. When trying to create something like suede or velvet this is much more of a problem, as opposed to something much less subtle like leather or glass. On or off is not really ideal in terms of workflow for the creator, as it would require considerable uploading, editing and re-uploading of items in order to produce the desired result. Messing with things is not only critically important, its a fun part of the creative process, now removed.

Another aspect which concerns me is the fact that normal maps applied by themselves provide almost no noticeable difference in appearance. It seems to only have an effect when both normal and specular maps are both applied. This produces a result which makes everything look shiny or wet, which is not a good thing in all cases. This may be a result of the inability to adjust the normal map once applied, as stated above, though it appears to be systemic rather than feature-specific. Is this a limitation of the rendering engine?

Considering that the application of materials has a potential effect on the download calculation of the object (land impact/prim count) the need for both normal and specular when specular is not desired seems to add to the resulting calculation even more than it has to.

I hope that these concerns will be addressed at some point in the future, they are really important to the use of this feature in an effective manner.

[Frawmusl]

I agree with a lot said here, but I have been able to achive normal mapping results that are noticeble without specular mapping? So on that single point I'll disagree ^.^ 
But as of now... Yeah SL is heading to a slippery place with specular mapping (Pun intended)

[Maxwell Graf]

Additionally, it would be extremely useful if we could use materials on terrain. It seems kindof crazy that we cant.

[Poenald Palen]

Most things with computers can be measured.

Materials repositories (blender has one) and materails for sale are common enough in the 3D world that I know some people will show some settings and maybe even make a wiki page at the SL wiki might start? Of course, this works more for mimicing real world look materials, not fantasy or heavily stylized materials.

I find it interesting that stuf with baked shadows till sells, even though many GPU cards for sale now (sometimes under $50 even) that can render shadows but I see stuff around and still doing OK with shadows or amient occlussion looking stuff. I wonder how many will see this stuff everyday?

[Harry Hyx]

Oh and also materials on on the default SL avatar would be amazing. As of now the shading on the face is umm...how can I put this lightly...ugly. I think it would benefit greatly from some new normals.

[WolfBaginski Bearsfoot]

The Lindens chose not to implement materials on the actual avatar surfaces, and I'm not sure why. Perhaps they're wary of the rendering cost. Another possibility would be an Avatar 2.0 project: that would need new content, and making materials available for that might make sense.

What might be useful is a set of normal maps that would work with library textures. I'm not sure they would be a good idea for ground textures, and I doubt they would be needed for some, but there is the "redwood" texture. There are others in the Buildings folder. The "Shingles" texture is a bit more than just grooves. There are the textures used for Linden Homes.

But I am not sure that there is a huge advantage for the irregular, almost-noise, patterns there might be in gravel drive-ways and in some wall finishes. An existing baked-shadow texture could have a lower rendering cost.

[Drongle McMahon]

I think it would be very helpful if we had a new material asset type. It would just be a set of three texture ids, plus the other simple material-related parameters. This could the be applied to an object/face as a unit, avoiding separate loading and adjustment of all the parameters every time a new face is textured. It would greatly encourage the use of re-usable general-pupose combinations, which could in turn reduce overall resource consumption.

[Poenald Palen]

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Drongle McMahon wrote:

I think it would be very helpful if we had a new material asset type. It would just be a set of three texture ids, plus the other simple material-related parameters. This could the be applied to an object/face as a unit, avoiding separate loading and adjustment of all the parameters every time a new face is textured. It would greatly encourage the use of re-usable general-pupose combinations, which could in turn reduce overall resource consumption.

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Exactly what I was hoping! This also is in line with the repository sort of thing. Some people have made one for blender, and it is good to learn and has a lot of good starting points with obvious worry of where they got the texture and all that, but some are totally procudural and we already have texture sorce issue and just change it if you feel the need, right? So, yeah, this is exactly what we needed because it also fits right into the texture selling market that exists where people can sell seamless or otherwise useful textures for people to apply to thier objects they buy, either sculpt mesh or even prim builds.

Maybe a scipt can be used to apply them all and a texture maker would simply say "-insert name of script here- Script compatible" OR open source and include one...I really should be going, and maybe I will explore this myself since I can script a bit.