help with uvw mapping

[Chisel]

does anyone know how to use the uvw feature or the uvw map? in vray for sketchup? if u do please explain. thanx in advance.

[thomthom]

Re: help with uvw mapping

You map textures by using Sketchup. That provides UV coordinates for V-Ray.

If you have mapped a texture in SU to fit an area of 1000x1000mm and then add a bump map where you set the UV Repeat values to 0.5 the bump map will fit an area of 2000x2000mm. If you set the UV values to 2 then it'll fit an area of 500x500mm.


If you do not apply a texture in the Diffuse layer, then all textures you add in the other layers will fit to 25.4x25.4mm (1x1inch). And to get your textures at the correct size you'd then have to calculate the correct repeat values.

It's therefore best to map your textures in SU as that gives a much more reliable and predictable result. Using only the V-Ray UV values might be a hit and miss.

[remon_v]

Re: help with uvw mapping

how about texturing rounded things..... for example the trunk of a tree?

[thomthom]

Re: help with uvw mapping

You have to do that manually. V-Ray doesn't offer any extra UV mapping tools.

There's an plugins for SU you might want to try to mapping cylindrical objects: http://forums.sketchucation.com/view...?f=180&t=10404
And if you search Sketchucation for texture mapping you'll find several thread about mapping textures to non-planar surfaces.

[Chisel]

Re: help with uvw mapping

then do you kno how to use this one? can it be used as in 3ds.

[thomthom]

Re: help with uvw mapping

I've never worked out what that Map type do. What do it do in Max?

[Jackson_cg]

Re: help with uvw mapping

Interesting discussion (never even noticed the UVW map type before), but why is this topic in the Gallery? :-\

[remon_v]

Re: help with uvw mapping

Jackson.... how did u do ur trunk texturing in the long grass topic?

[Jackson_cg]

Re: help with uvw mapping

All the trees (actually there only two different types in that image) are clipmapped billboards with semi-circular trunks with just projected textures on them. As you never see them from any angle rather than face-on it doesn't matter that the projected texture is distorted on the edges.

[dalomar_cg]

Re: help with uvw mapping

That UVW texture really doesn't do much, it just maps the texture coordinates to colors directly, so it actually looks like something you'd see in a color picker.

[frip51]

Re: help with uvw mapping

I also wondered whether it could be useful, but it seems that it's just a bitmap.

What can you do with it in 3dsmax?