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egearbox
11-24-2008, 06:36 AM
I'm trying without success to use FiberFX to add some vegetation to a landscape. I created a 10km sphere as a test object to isolate the issue I was having. The preview in the Layout window looks OK (pic 1) , but no fibers appear in VIPER or the Render windows (pic 2). After some tweaking, I was able to get fibers to appear by increasing the Fiber Width from 500% to 500,000% (pic 3). Is there a better way to grow fibers on large objects?

Sekhar
11-24-2008, 07:52 AM
Increase scene edge limit on the etc tab and see if that fixes it.

egearbox
11-24-2008, 10:50 AM
No, increasing the edge limit didn't fix it (although I was able to crash LW once or twice). I am able to get the fibers to display by increasing their thickness to a huge number, like 500000%, but I'm wondering if that's because some other setting is out of whack. Screen shot of FiberFX settings attached...

Sekhar
11-24-2008, 11:19 AM
Sorry, my bad - you clearly said it was a render issue, not preview. I've had this issue too when the object is large, which makes the hair thin in comparison. Increasing the width (like you did) is what I did too, and that seems like the right fix. I'll be interested as well to see what others say.

egearbox
11-24-2008, 11:31 AM
Aha! I found this in the FiberFX manual (never hurts to RTFM once in a while):

"Fibers further away are smaller in screen space and are more transparent. The percentage is based on human hair which has been measured at 0.017mm to 0.181mm with blond hair being the thinnest and black hair the thickest. At 100% width a fiber is calculated using a median value of 0.05mm."

Seems like they should put that information right on the FiberFX settings panel, or maybe dispense with the percentage and let you specify fiber thickness directly in mm. Having it as a percentage seems kind of weird.

The default fiber (500%) thickness is about .25 mm then, and my 500000% thickness fiber is about 250mm (10 inches) across. I guess the secret is just to keep jacking that number up and up until you get the results you want!

Sekhar
11-24-2008, 11:55 AM
Actually, I wouldn't do that - because it wouldn't reflect the real world. Imagine a 1m square with thin blades of grass, and then make it a 1km square. It wouldn't be right to jack up the width of the blades by x1000 just to make the grass appear. I would keep their width the same and jack up the density (and increase clusters, as necessary).

egearbox
11-24-2008, 02:23 PM
Actually, I wouldn't do that - because it wouldn't reflect the real world. Imagine a 1m square with thin blades of grass, and then make it a 1km square. It wouldn't be right to jack up the width of the blades by x1000 just to make the grass appear. I would keep their width the same and jack up the density (and increase clusters, as necessary).

In most cases I'd agree with you, but in this case it gives me approximately the look that I want. (And it's certainly better than modelling an entire landscape by hand.)

Thanks for the quick response(s)! :D