on material editor some questions

[han3d]

when i create a material
under options dialog
what is reflect on backside
and cutoff options does
as a map type what is acolor
and what does uvw
under reflection if i lower subdiv from 8 will render speed improve

[joe_b]

Re: on material editor some questions[CAN ANYONE REPLY THIS]

what is reflect on backside

I can't think of the exact definiton of reflect on backside. Perhaps Damien can help you with this one, or Gijs if he comes across this thread.

and cutoff options does

The cutoff is a threshold for determining when transparency rays should stop being traced.

as a map type what is acolor

the AColor texture is just a means of having a texture that is just a solid color and alpha value.

and what does uvw

UVW is the standard way of referring to texture coordinates in 3d space. Its like xyz except in texture space.

under reflection if i lower subdiv from 8 will render speed improve

Yes less subdivs will be faster, but less quality for blurry/glossy reflections/refractions.

[dalomar_cg]

on material editor some questions

From Spot 3D

Reflect on back side - if this is true, reflections will be computed for back-facing surfaces too. Note that this affects total internal reflections too (when refractions are computed).

[han3d]

on material editor some questions

ok then for a normal non transparent material no need for backside option i assume
so what if i lower or higher the cutoff option what will its effect
and can i use a colour image in acolor material slot
i know uvw but i cant figure out how can i use it as a map can you give me an example

[joe_b]

on material editor some questions

ok then for a normal non transparent material no need for backside option i assume

Right

so what if i lower or higher the cutoff option what will its effect

It will affect the quality of transparency/reflections. if you want quicker transparency calculations you would make the cutoff higher, but you will have less quality in the transparent objects. If you want it more refined you would make the cutoff value lower.

Cutoff - this is a threshold below which reflections/refractions will not be traced. V-Ray tries to estimate the contribution of reflections/refractions to the image, and if it is below this threshold, these effects are not computed. Do not set this to 0.0 as it may cause excessively long render times in some cases.

and can i use a colour image in acolor material slot

If you want to use a bitmap - then you should be using a bitmap texture.

i know uvw but i cant figure out how can i use it as a map can you give me an example

The UVW texture map just displays whatever UVW channel / provider you have as a map. It converts U -> Red V -> Green and W -> Blue. I'm a programmer, so I don't know what usage the UVW map may have creatively, but it is just a map made available to us from the V-Ray SDK.

Spot3d has a lot of information on VRayMtl parameters. Many of these params are shared with V-Ray for Rhino / SketchUp

[dalomar_cg]

on material editor some questions

You may not want to have reflect on backside disabled for refractive materials. Basically that would cause there to be no internal reflections, which would kinda lend itself to a wierd look. Test is out and see what works for you, but I usually leave it enabled.

[Jean-Paul Paloux_cg]

Re: on material editor some questions

when i create a material
under options dialog
what is reflect on backside
and cutoff options does
as a map type what is acolor
and what does uvw
under reflection if i lower subdiv from 8 will render speed improve

han, are you a kind of advanced web motor based on real good AI generating good questions in php forums ? you look like typing like a robot...

[dalomar_cg]

on material editor some questions

If he is I'll give it up to that programmer. If he isn't then I invite his questions, and also suggest a quick (or long) visit to the source for vray answers (thats Spot 3d if you didn't know)