Tapering for VRayFur

V-Ray V-Ray Common Tutorials, Tips & Tricks
1

You can simulate tapering of the fur strands for VRayFur if you map the opacity of the material along the strands, so that they are more transparent towards the tips:

Best regards,
Vlado

2

That’s a great tip Vlado…

Does this work with the refraction map with IOR 1.0 trick for opacity? or only if you use the opacity slot of the material?

3

You can do that, of course, but in my test it was slower with refraction than with the opacity map.

Best regards,
Vlado

4

nice!

are there any plans to implement styling in vray fur btw?

5

Ah, yes, whatever happened to that Vlado? I can clearly remember you saying that this was going to be implemented in the 1.5 final.
What happened?

6

I still have shag installed, just for this one hope.

7

Well, it works, but it needs some more development time; I’ll see if I can release something separately from V-Ray. It is essentially a vertex paint modifier, but designed to generate textures specifically for V-Ray fur.

Best regards,
Vlado

8

That’s a good tip, thanks!
Would you consider adding a totally flat geometry type as well? Basically just a plane with as many height segments as specified in the knots setting. The plane could have normal UV coordinates, and would be useful for doing special things like feathers, or for mapped grass cards for distant objects. I guess the challenge to work out is the orientation of each fur object around the z axis?

9

Re: Tapering for VRayFur

Can anyone tell me how to “map the opacity of the material along the strands”?

thanks!

10

Re: Tapering for VRayFur

You need to use the W mapping coordinates. So add a gradient ramp to the opacity slot of the fur’s material, and change the mapping from UV to WU.

11

cool tip. that’s exactely what i need for an upcoming interior-shot.
thanks vlado.
ale

12

Here’s a quick samplescene if anyone needs it. (max 9/VRay 1.5)
Download

13

Hey torgeir thanks a lot!

14

thanks Egz!

15

Is it normal that when you put any texture into the diffuse slot, the rendering becomes very very slow? For example I swapped the gradient from the opacity to the diffuse channel. If I try another texture, even simple ones, it gets very very slow.

16

yes ive seen this as well. Its quite a noticeable difference. And thats just in the diffuse slot. I can’t imagine how bad it is for opacity.

17

Works fine for me on Egz’s scene (I just instanced the gradient ramp texture from the opacity slot to the diffuse one).

No diffuse, no opacity map: 23 s
With diffuse map, no opacity map: 19 s
No diffuse, with opacity map: 54 s
With diffuse, with opacity map: 56 s

Obviously, the opacity map adds to the render time, but the diffuse one does not… not sure what may be the issue in your tests though - this is on 32-bit 3ds Max 9.

Best regards,
Vlado

18

In my file, rendering goes from 5 to 30 seconds when I add a diffuse map. And it’s 90seconds with opacity map and no diffuse.

here’s the file and 3 renders:

www.aversis.be/vrayrhino/fur.zip

It’s in max 9 64bit, vray 1.5 rc4

19

7 sec with diffuse and opacity here in your scene flipside.

max 9, 32 bit 1.5 RC5…

20

Must be the RC4 then…

V-Ray 1.5 final 3ds Max 9 64-bit: without map: 13.2 s, with map: 14.2 s.

Best regards,
Vlado