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Re: Working with glass and liquid.
Posted: Thu Apr 22, 2010 5:59 pm
by Voidmonster
radiance wrote:
once thing to take into account is that pathtracing kernel uses russian roulette to terminate paths,
so after 3 bounces, it starts the russian roulette, and arriving at a maxdepth of say 32 is something that will only happen in very small cases.
basically, after 3 bounces, there is a near 50% probability that the path will be ended at every next bounce.
however octane does'nt do this purely randomly, it does take into account the value of the path, but only when the rrprob option to the kernel is set to 0, eg 'auto'.
Radiance
Ahhh. That's what that parameter does... And the further you turn it up, the more like playing Russian Roulette with a clip-loader it becomes.
Re: Working with glass and liquid.
Posted: Thu Apr 22, 2010 6:01 pm
by radiance
Voidmonster wrote:radiance wrote:
once thing to take into account is that pathtracing kernel uses russian roulette to terminate paths,
so after 3 bounces, it starts the russian roulette, and arriving at a maxdepth of say 32 is something that will only happen in very small cases.
basically, after 3 bounces, there is a near 50% probability that the path will be ended at every next bounce.
however octane does'nt do this purely randomly, it does take into account the value of the path, but only when the rrprob option to the kernel is set to 0, eg 'auto'.
Radiance
Ahhh. That's what that parameter does... And the further you turn it up, the more like playing Russian Roulette with a clip-loader it becomes.
yeah, the slider controls how many bullets you put in the gun.
if it's at 0.5 half the gun is full of bullets, if it's at 1.0 the gun is full of bullets, if it's at 0.0, it's not empty, then it's automatic, eg it depends on the quality of the ray.
Radiance
Re: Working with glass and liquid.
Posted: Fri Apr 23, 2010 9:02 pm
by justix
Not as realistic (yet) as voidmonster sample but hey...first test with RC1 release and I'm impressed..no fireflies
(I though my old crappy 8800GT would not be able to handle MTL) and the image look already cool after 8 Minutes!!! if only my GTX470 was already here....postponed again......yaahhhh!!
Re: Working with glass and liquid.
Posted: Fri Apr 23, 2010 9:11 pm
by radiance
yeah, the fireflies on very rough glossy materials weren't caustics but they were the result of a bug that's been fixed in 2.1
Radiance
Re: Working with glass and liquid.
Posted: Fri Apr 23, 2010 9:33 pm
by justix
radiance wrote:yeah, the fireflies on very rough glossy materials weren't caustics but they were the result of a bug that's been fixed in 2.1
Radiance
awesome.. and unless very much mistaken looks slightly faster than the previous release or am I going slightly mad?
Re: Working with glass and liquid.
Posted: Sat Apr 24, 2010 3:56 pm
by pixym
This is what I get in 2mn with the Glass sample scene in Thea render beta
Re: Working with glass and liquid.
Posted: Sat Apr 24, 2010 4:00 pm
by radiance
pixym wrote:This is what I get in 2mn with the Glass sample scene in Thea render beta
for a fair comparison algorithm wise, you should disable MLT and use pathtracing, or await MLT in octane 2.2.
These kind of scenes are a nightmare to render without MLT.
Radiance
Re: Working with glass and liquid.
Posted: Sat Apr 24, 2010 4:19 pm
by justix
Complete render of my previous post.
1600x1200 - 1600 maxsamples render time 3:26.14
it looks ok to me except some noise area in the liquid that I immediately identify after few minutes but I though that it would clear off.
Re: Working with glass and liquid.
Posted: Sat Apr 24, 2010 4:26 pm
by radiance
as said these kind of scenes require MLT to render efficiently,
currently it's just very innefficient brute-force rendering.
Also, a faster GPU would help too
Radiance
Re: Working with glass and liquid.
Posted: Sat Apr 24, 2010 4:28 pm
by pixym
radiance wrote:pixym wrote:This is what I get in 2mn with the Glass sample scene in Thea render beta
for a fair comparison algorithm wise, you should disable MLT and use pathtracing, or await MLT in octane 2.2.
These kind of scenes are a nightmare to render without MLT.
Radiance
I am not at office right now, but it seemed to be the unbiased engine...
Edit: I dont know what Thea uses... as unbiased algorithm.