Thanks for all your replies. This was more like what I was looking for.

We have to look at ice-boy's concept of the necessity for tweaking a valid one. And for those who like that sort of thing - me being one - I'd like to see a discussion-group dedicated to how to incorporate colours and reflection/refraction/conservation of energy and all the rest and develop shaders that then make the most of that material. Out of this are going to come sophisticated solutions and some not so clever. Doesn't matter, as long as people see that GC is important and try to do something about it.

The one-button script to fix simple materials has a lot of merit, particularly for the double-click / render crowd. Yes Bill, I believe if it were marketed correctly, you would sell it quite well. Let's not forget we are addressing a niche market, here, one that will evaporate as people migrate to Poser Pro, so make it simple and soon. The resultant shaders will no doubt produce a better render than not having done anything to the material at all.

However, for ultimate realism, some of us more pedantic artists are going to want to learn techniques and avoid pitfalls associated with GCing some of the more shader-rich materials out there... and there are a fair few.

Which brings up a point...

Quote - It occurs to me that while my technique is fine for shaders authored by me via matmatic, it's not particularly a good workflow if you're trying to take an existing shader build by someone else with a crapload of nodes and all you have is the material. In such cases, you're forced to reverse-engineer the shader and make an equivalent Matmatic script. That's a pain in the butt.

Yep, gone that route, Bill. It's an education in shaders... I can pretty much recreate in code most manually-strung-together shaders I run into. Your 52-node leviathan skin shader would not be one of those, since it's created with a very sophisticated maths that I am struggling to get my head around - note the work "struggling", which denotes effort being expended. However, I've been fiddling with Matmatic and other people's shaders long enough now to come to the realization that some material developers went into the material room and without any understanding of the actual physical properties of the materials they were trying to recreate mucked around until things "looked right". Which means that they set reflection and diffuse values in nodes and on PoserSurface unrealistically high, which was analogous to setting your lights too high... they were kinda on the right track, but weren't really addressing material optimization correctly. So, what you end up dealing with is a bogus shader.

Now, to fix it. You could go in just about any direction you want to with a shader... develop a completely new look which I'm not completely certain even the original developer had in mind. I recently GCed a very simple item - the Hongyu Jersey dress, default colours - and turned it into a much lighter grey (as opposed to a dark brownish colour) and ooohhhh, didn't the underlying pattern suddenly come out beautifully. Was this Hongyu's original intent, though? Who knows? End of the day: who cares? Well, some might... some want that colour, just corrected, not something completely different.

So, we're going into a very interesting area here, and we haven't even looked at tricky areas like reflective / specular aspects to our objects.

And THIS is why I saw a crying need to discuss this concept further. I saw myself writing Matmatic "solutions" that would faithfully recreate a GCed version of the original shader, but whoa, was that really what I want.

So, a topic of exploration could be: what constitutes a "valid" shader? What things do we need to watch out for to prevent violating the laws of nature? The Kerkythea Materials Manual discusses conservation of energy quite thoroughly, but can one faithfully apply all of those principles in Poser?

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