Cineversity

Howdy,

I guess this is a fairly esoteric Arnold for C4D question. I’m a long time C4D user, but new to Arnold. I recently hopped on the Arnold bandwagon and started learning with Arnold 5. Been plowing through the MographPlus’s “The Ultimate Introduction to Arnold 5 for Cinema 4d” and really digging it so far. However, the section on the new Arnold 5 Standard Hair shader has left me wondering…

Is it possible to make fur that grows in color patterns? For example, tiger stripes or leopard spots?  I’m guessing it’d mean connecting a texture that has UV coordinates to the Color input of the standard surface shader, but I’ve not been able to figure out exactly how to do this and get the result I want. For example, connecting noise does, indeed, result in noise coloring the hairs, but NOT in the way I’d hoped… i.e. I’m tying to get patches of black and patches of white, where each individual hair’s root has the same color as the tip.

Any advice would be appreciated.

Thanks!
- Greg Reynard

Hi Greg Reynard,

I have no current version installed of Arnold. So, here is only a little finding:
https://support.solidangle.com/display/A5AFCUG/Standard+Hair:+UV+Coordinates

Yes, that’s about Hair. There is nothing I was able to find about fur.

IF you use Cinema 4d’s Fur, check the Fur>Attribute Manager> Color> Surface Options

I’m not certain if the C4D noise shader is a good idea to start from, try to stay in an image based source, until it is working.
C4D native example
https://www.amazon.com/clouddrive/share/KJdM5L6aTzL56BnMMeoTGeitIWNQSmBh6rIXDlZGvgY

Again, I have no access to Arnold 5.

All the best

Thanks so much! That link was very useful. I spent about half an hour looking for an “Export UV” option on a C4D Hair object, and finally realized that I needed to add an Arnold Parameters Tag and THAT is where the Export UV option was located. Also on that site I found an article about how you can use a state_float node with its value set to bV (This value determines the color along the length of the hair, from root to tip), connect this to the input of a ramp_rgb node, then send different colors or textures to the Color inputs of the ramp. The ramp is connected to the Diffuse Color input of the Arnold standard_hair shader, and the bv value lets you have different color values along the hair when traveling from root to tip.

BTW, Cinema 4D noise worked fine as a source to color the hair.

As for hair vs. fur, I don’t think Arnold makes a distinction. If you want to render fur, you need to use a C4D Hair object, and a Standard Hair shader.

Thanks again!

Cheers,
- Greg

You’re very welcome, Greg.

Yes, the Arnold Manual is certainly useful. I hope others will have an advantage using your findings.

It sounded to me like that it should be the Hair Object , not the Fur Object to create the the effect, thanks for confirming.

Enjoy your weekend