environment fog + 3D noise

[X14Halo]

I can get my environment fog to work great, but when I try to plug in a maya 3D noise texture it does not look correct. I am using vray rect lights, so I tried plugging the 3d noise into the rect texture slot of the light. I also tried plugging it into the color slot. Putting it into the color and/or density of the environment fog itself makes the render time about 100 times longer, so that is not an option. (I can't even tell if it would look correct anyway because of the huge increase in render time.) Any idea on how I can create a nice environment fog render with a 3D noise to break it up?

[vlado]

One option would be to use the NoiseMax texture (with a 3d placement node) - I think it calculates faster than the Maya volume noise. You can create it from the Create > V-Ray > Create texture from V-Ray plugin menu and then plug it into the density slot of the environment fog.

Best regards,
Vlado

[Metzger]

Maping a noise to the V-Ray vol fog Density has been super slow since 2.0 and a bit earlier. I remember when it was first supported it was much faster. Perhaps I am imagining this. Rendering fog with IES lights is quite stunning. Everyone should try it.

[X14Halo]

Yea, it is super slow whatever I do. Hopefully it will be fixed down the road. It just renders black when I use the noisemax 3d texture. I will definitely try it with IES lights, sounds interesting.

[vlado]

Well, for V-Ray 2.0 we implemented the Maya noise exactly as it is implemented in Maya itself, and that is slow Before that we used our own noise generator, which was faster, but produced quite different results.

I'm attaching a simple scene with environment fog and NoiseMax texture.

Best regards,
Vlado

[X14Halo]

Thank you very much vlado. I now understand why it is taking so long to render. The scene you sent renders very fast, but once I scale everything up to match my scene size (which is pretty big) it slows wayyy down. I guess i will have to stick with smaller scenes or find an alternate method of generating the fog. Thanks again.

[X14Halo]

one more question...how did you link the cube to the environment fog? I usually make a shader and then plug the environment fog into the volume slot of the shader. perhaps that's what I was doing wrong?

edit: nvm I see now...relationship editor. everything works perfectly now, thanks again.