Page 1 of 1
Volumetric light
Posted: Thu Jun 07, 2012 5:08 am
by baka
Hi, I'm trying to recreate the volume fog effect from 3ds max but ran into a snag, it appears it's only possible with ISL (which is rocket science for my brain) and even with it I haven't found any examples replicating the volume fog effect. I'm pretty sure I'm SOL but I figured I'd ask if it's possible first before giving up on it
Re: Volumetric light
Posted: Thu Jun 07, 2012 5:50 am
by Zom-B
No ISL needed... it never was
Try this one here, follow the link on the bottom for a quick "how-to"
Re: Volumetric light
Posted: Thu Jun 07, 2012 6:03 am
by baka
I'm not trying to get the basic volume light, I need to replicate the 3d noise effect (fractal/turbulent) volume fog has, which from my understanding can be achieved with ISL.
Re: Volumetric light
Posted: Thu Jun 07, 2012 6:15 pm
by Zom-B
ok, now I got it
I remember that fused and lyc created such a material, but it rendered quite sloooow ^^
Maybe they could release the code here?
(stupid me forgot to give a link for the classic fog in previous post: http://www.indigorenderer.com/materials/materials/125)
Re: Volumetric light
Posted: Fri Jun 08, 2012 1:03 am
by CTZn
Hi baka, here is one cloudy fog material: about half of the volume is thin air, the rest is smoke.
The (identical) shaders are applied to the material's medium, in absorbtion and scattering. You can disable the absorbtion for a slightly faster rendering, and control both values by modifying the last multiplicator (50.0). Clouds scale are controlled by the 30.0 number.
Let me know if you need a different shape, I'll try to make it for you.
Here's the shader both parameters are using:
Code: Select all
def eval(vec3 pos) vec3 :
let
fracNoise = fbm(pos*30., 8)
in
vec3(if(fracNoise>0.0, fracNoise, 0.0)) * 50.0
Re: Volumetric light
Posted: Fri Jun 08, 2012 1:09 am
by baka
Thank you CTZn, I'm gonna play around with the parameters and see if I can get the look I need.