Lights, Camera, Inaction

There seem to be some misconceptions as to what exactly can be achieved with the new materials in Second Life. Some people are left feeling a little underwhelmed when they discover that the Materials system doesn’t deliver the results they hoped it would. We can see some good threads in both the Second Life official forums and over at SLUniverse where people are learning the powerful or not so powerful features of the tools, and this is good to see as healthy discussion helps everyone.

On the Second Life forums, Creator Linden has created a thread entitled Materials Support and Tips, which is a very handy read. What we see there is people coming to terms with what can and cannot be achieved. Another handy read is Advice? Advanced Lighting Model – No Effect On Materials Applied In world. That thread really emphasises how important lighting is to materials, something I hadn’t initially grasped myself, although there are some obvious clues when you consider you need to have advanced lighting turned on to see materials!

I had created some wooden planks, which when I first uploaded them, worked as intended, they had a bit more depth to them than the flat texture provided. However when I changed the day cycle to another setting, the depth was lost. Drongle McMahon was very helpful in pointing me in the right direction regarding how light works in a post over at SLUniverse:

Specular highlights only appear at a narrow angle between the incident light and the camera. You can control this angular distribution globally with the “glossiness” parameter, and that does affect the range of lighting conditions you can see the effects of the mormal map. It also affects the brightness, and you can alter that independently by changing the specular colour (below the spinners) to shades of grey. This all works with the blank texture in the specular map. You can get good woodgrain effects this way. Adding a proper map here gives you better, spatial control over the intensity (and colour). The sharpness (glossiness) can be controlled spatially by using the alpha channel of the normal map. Using these can make more pronounced effects.

The normal map only affects specular and diffuse intensities. It does not produce ambient occlusion or shadowing that would be there if the bumps were really there. This is why woodgrain-like effects are hard to see at angles where the specular effects are low. Without extra lights, that means you only see them at very limited light/camera angles. On the other hand, the environmental lighting comes from all round. Turning this up is like the old shiny. It can reveal the effects of the normal map, but it also tends give that overall wet look which is not very good for wood. Unlike the specular light, which is purely additive, it also darkens the diffuse texture as the shininess is increased, which is perhaps not what you want here either.

Drongle McMahon is very helpful in the official forum too, I’m quite a fan of Drongle.

The SLUniverse thread: Materials Project Viewer is Out To Play With is quite an epic thread, which started in April. However it discusses a wide range of issues, from lighting, to land impact issues, to people picking on and defending the poor old torus.

Now being at SLUniverse it’s a little more direct than the threads on the Second Life forum and may include a little profanity and some serious grumpiness but there is a lot of useful information there and a lot of factors to take into consideration and as I said at the start of the post, this healthy discussion on materials is extremely useful.

Materials are a very useful addition to the Second Life world but they don’t need to be used everywhere and in some cases they will be more trouble than they are worth, but when used well they can produce some extremely impressive results, it’s getting your head around when and how to use them that is the challenge, just because you can use them doesn’t mean you should and ensure that you test your materials ready creations under different lighting conditions.

This is a bit like Mesh in many regards, people think that prim building is outdated and that Mesh rocks. Mesh can rock, but there are times when the trusty old prim cube can work just as well, indeed in some cases better, than a Mesh equivalent. Don’t discard the old just because the new sounds sexier. Personally I still feel that for floors and walls the only advantages for Mesh are UV Mapping one texture on a Mesh floor or wall as a single texture, when you could use as many as six inworld, or constructing your build with the walls and floors already joined, cutting down on land impact scores. The downside of that is that end users won’t be able to modify them as easily as they could an inworld prim and walking on Mesh floors has reportedly been problematic, with some people using an invisi prim to make them work as expected, which has its own issue if an end user decides to edit linked parts!

So yes, Materials are good, they are a welcome addition and can improve performance, but they will not suit all cases, so don’t feel that they must be used, there are options.


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