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View Full Version : Im interested in peoples workflows for tuning materials?


Sully
09-10-2009, 03:55 PM
I've been trying to think of how materials behave in the real world under different lighting conditions, for example: reflective objects in a dark environment will still be visible over non reflective objects because of its reflective properties therefore giving you key info on how reflective it is in comparison to other materials. Also you can often gauge how glossy a material is by looking closely at the reflection of the light source in that particular scene. These are two pretty naf analogies but i'm sure there are many others I could have used but just cant think of them right now, but hopefully you get what i'm trying to say.


So when it comes to 3d material do any of you use these kind of principles to quickly tune your materials? Do you take your materials into different environment situations to gauge how they react under certain situations? or do you just tune them in the scene to look right from a certain view? From my experience a material set up from one camera angle will look like a completely different material when looked at from another. Is it possible to represent a material that will work from any angle or lighting situation with the tools we have currently? At the end of the day this all boils down to real world material BRDFs and from what I know there still isn't a shader out there yet that can read BRDF scanned data.
So saying this do any of you build your material libraries in this fashion before you take them into your scenes?

bonestructure
09-10-2009, 06:41 PM
I mostly use custom maps created for specific scenes. As such, I have to tune the texture for that particular scene, lighting, color balance and all. And even if I use procedurals, I have to tune for that particular scene. A chrome or brass or glass texture may look good in one scene, and not so hot in another with different lighting. I tend to try to make my own procedurals as well. At the moment, I'm trying to work out a good seawater texture for Vray. It involves experimenting and all. And even if I create a great seawater material, it may go all wonky when I put it in a scene and I have to futz with it more. Really, I think you have to go scene by scene, adjusting reflectivity, specular, bump, displace, the whole procedure.

rdane1010
09-13-2009, 09:55 AM
Houdini is the best software I've come across for this and its all I use now for material shading... the VEX networks in it let you control every aspect of the material, the way the light interacts and everything... something I recommend checking out if you want to get really into material shading.

As far as materials looking different from different angles.. I don't know what software you're using but that shouldn't be the case if you have the lighting set up properly, if you are using surface mapping make sure to use displacement maps instead of bump maps as bump maps could cause the issue you are describing

SYmek
09-13-2009, 08:31 PM
So when it comes to 3d material do any of you use these kind of principles to quickly tune your materials? Do you take your materials into different environment situations to gauge how they react under certain situations? or do you just tune them in the scene to look right from a certain view? From my experience a material set up from one camera angle will look like a completely different material when looked at from another. Is it possible to represent a material that will work from any angle or lighting situation with the tools we have currently? At the end of the day this all boils down to real world material BRDFs and from what I know there still isn't a shader out there yet that can read BRDF scanned data.
So saying this do any of you build your material libraries in this fashion before you take them into your scenes?


The thing you're cruising around is sometimes called "pallete". Pallete is a set of material's parameters with accompanying lighting conditions, which allows artists quickly jump into predefined look of certain asset (e.g. "Smith's barn at night"). Palletes are prepered during look development process and used as a starting point for tweaking particular scenes. They consist with both materials and light rigs.

There is nothing like a general material that will look great under any conditions, so for example quite often single object will have different materials for close up shots and for totals. Another evident reason to switch materials is optimazation.

On the other hand, if your object's look depends too much of camera's angle and it's pretty unstable, there could be something wrong with it. Well prepared material (or production shader) should behave at least predictible. It was (should be) designed with particular usage in mind and (should) behaves properly in it.

So, to answer your question, you won't escape from tweaking your setups, but well prepared materials should minimaze that unforune circumstance ;)

cheers,
skk.

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