View Full Version : Fiber Effects Width?

01-27-2009, 06:17 AM
How do you get fiber effects to make blades of grass? I can't get the fibers wide enough? Much better luck in SAS Lite! Has anyone made believable grass yet?

01-27-2009, 07:00 AM
The Pixel Filter side will struggle to get actual thick blades. Clump and Tuft help, as does layering. But to get really thick blades the only way is to use the Fiber Modeler, but the fibers are then actual 3D geometry, which makes them only useful for small areas, until we have some kind of instancing in LightWave.

From the FFX manual:

Fiber Width

Controls how thick or thin fibers appear. Thinner fibers are more transparent and build up density slower, whereas thick fibers are less transparent and build up density faster. Model scale has an effect on fiber width, as does the distance to camera.
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.

01-27-2009, 08:08 AM
Okay, here's my attempt after about 10 mins playing.

Scene files attached.

01-27-2009, 08:21 AM
Okay, here's my attempt after about 10 mins playing.

Scene files attached.

Hey thanks for going through all that. I will check out the file soon. I must admit, SAS Lite was easier to deal with. I'm sure I'll get the hang of it.

01-27-2009, 08:26 AM
Played with SASLite once, couldn't get on with it. I guess it's what you're used to!

01-28-2009, 10:14 AM
theres a setting for thickness in FiberFx, its not in front of me right now, but I've been able to affect the width.

its named weird, it goes on a percentage of the length or something, so the value is insane, and the way it works is kind of backwards, but its there.
I'll drop back in when I have a minute to go look at the panel and let you know what its called.

01-28-2009, 11:14 AM
The best way to get "thickness" in FiberFX is to use "volume only" setting. Your render will take longer, but you will have fibers that are very solid.

My other approah is to crank up the thickness to 30000 - 100000 %, since you want something that's way beyond the thickness of a human hair.

01-28-2009, 11:45 AM
I have seen some really nice grass out of FFX a long time ago, I'm not sure why some are saying it's hard to do. Just be aware of the scale of your model you are growing the grass from and crank up your settings like adam has said, especially if you want to get a close up shot. Do try the volume only setting.