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Matelot13
04-07-2009, 03:27 PM
Hello everyone
First real try with FiberFx. And I have two (main) issues :

1 - I get these patterns on my hamster's fur (separate surfaces for arms and body) - from various tries it seems to be coming from the bump, but I don't know how to adjust it (I actually don't know what "bump" does when it comes to hair)....

2 - This guy's fur is almost white. No matter how I set it up, through gradients, fiber U, simple color, It's always brown. How can I adjust that ?

jasonwestmas
04-07-2009, 05:34 PM
Please post screenie of your settings. Check out these tuts by William Vaughan.

http://www.nyclightwave.com/content/fiber-fx-tutorials-lightwave-95-william-vaughan

Mr Rid
04-07-2009, 06:57 PM
I'd love to know how to get rid of those 'lines'.

adamredwoods
04-07-2009, 08:02 PM
1. Add noise texture to the fiber bump channel?
2. Tip color settings? Specular color settings? I usually use the simpler color settings.

SplineGod
04-08-2009, 01:20 AM
This has been an ongoing problem among others with FFX.

jasonwestmas
04-08-2009, 06:31 AM
I used to get strange colors in the hair if I used a secondary specular color. Try it without that once if you are.

Matelot13
04-08-2009, 12:13 PM
Well, I managed to get something done. I got rid of the rings by turning off the self shadows. The color looks fine, but it's still not the one I set.
Working with FiberFX was quite frustrating, - I had at first separate surfaces for arms, eyes, ears, etc..., but when I cloned the settings I would lose the fur on one area, while another wouldn't apply to the assigned surface... Is there another way to add fiber to a surface without cloning ? I ended up using one setting for the whole body, and the fur it's not as fluffy as I hoped, but the image doesn't look too bad for a first try, so....

Kevbarnes
04-08-2009, 12:33 PM
Is there another way to add fiber to a surface without cloning ?

I had a similar problem recently when I instanced the settings to put fur on another surface I got render errors as if the unseen instanced mesh had transparent specular surface.

Anyway I resolved it by combining all the fur surfaces in one surface in modeler but isolating them with weight-maps and using them in Layout with a gradient.

Mr Rid
04-08-2009, 02:46 PM
Well, I managed to get something done. I got rid of the rings by turning off the self shadows. The color looks fine, but it's still not the one I set.
Working with FiberFX was quite frustrating, - I had at first separate surfaces for arms, eyes, ears, etc..., but when I cloned the settings I would lose the fur on one area, while another wouldn't apply to the assigned surface... Is there another way to add fiber to a surface without cloning ? I ended up using one setting for the whole body, and the fur it's not as fluffy as I hoped, but the image doesn't look too bad for a first try, so....

... except that it appears glowy luminous I think after disabling self shadows. Did you disable object self-shadow, or FFX self-shadow? Of course, the solution to a problem in a feature should never be 'just turn off that feature.' Self shadowing should work. I keep hearing the suggestion to apply a bump texture but it never has much effect.

I see that the lines show up on the underlying mesh when using trace shadows and FFX Shadow Type- point sample
72230
or interpolate.
72234

I imagine it ought to be possible to pre-bake the shadows into the fur while also saving render time... Pre- render the figure with only a color textured mesh (noFFX) with full shading (or even GI), using the Surface Baking Camera to save out a still or sequence of color UVs. In a 2nd pass, the UVs are then used to drive the FFX color texture where the shadows are already baked in the fur color. This should eliminate the artifacting and speed render time since the fur never actually has to be involved in shadow calculation. At least, thats how it works with Sas. Am sure FFX will throw some more curveballs as you McGuyver workarounds.

jasonwestmas
04-08-2009, 03:35 PM
I've had a few issues with shadow artifacts too but you really should toy around with your "T" texture settings for the geometry settings. I really think that those lines are showing up because your hairs are evenly spaced causing a pattern within the shadowing to show up.

Matelot13
04-08-2009, 03:43 PM
I tried the "T" texture, and got, well, different patterns (there's one on the cushion). I think the issue here is also that the fur is very short, partly because I modeled my hamster too fat, forgetting to anticipate the level of hair. So I cranked up the thickness, resulting in the glowing effect mentionned before.
I saw in the William Vaughan tuts that he often disables or at least turn down the FFX self shadow.

Mr Rid
04-09-2009, 04:38 PM
...
I saw in the William Vaughan tuts that he often disables or at least turn down the FFX self shadow.

Which seems ridiculous. Turning off self shadows is not a solution to getting self shadows to work correctly. May be fine for cartoony stuff but not photorealism. 'Ray trace' for 'shadow type' may be the only one that works.

jasonwestmas
04-09-2009, 04:53 PM
I tried the "T" texture, and got, well, different patterns (there's one on the cushion). I think the issue here is also that the fur is very short, partly because I modeled my hamster too fat, forgetting to anticipate the level of hair. So I cranked up the thickness, resulting in the glowing effect mentionned before.
I saw in the William Vaughan tuts that he often disables or at least turn down the FFX self shadow.

I would experiment with a very subtle UV scale texture to break up the pattern.

SplineGod
04-09-2009, 05:42 PM
Dave,
Much of the problems I see people posting about FFX seeem to be chronic. During beta these same issues or worse ones seemed to pop up on a regular basis. It wS quite frusrating especially during production. Much of what William showed in those demos werent applicable or useable later on because he was using an earlier beta version.