Indigo 0.8 test 1

Wedge · Post by **Wedge** » Tue May 01, 2007 7:29 am

Thanks for the information manitwo.

tizxx · Post by **tizxx** » Tue May 01, 2007 10:40 pm

If we use HYBID and BIDIRECTIONAL after few minutes or samples
the image go to dark mode...

If you turn off BIDIRECTIONAL all works fine...

then the question is...

when we must use Hybird mode? Only on direct light: SUN LIGH ONLY

see these images

manitwo · Post by **manitwo** » Tue May 01, 2007 10:46 pm

If you have much direct light i would use "Bidir PT" and when you have much
indirect and/or much glass/caustics i would use "Bidir Hybrid".

Kosmokrator · Post by **Kosmokrator** » Tue May 01, 2007 11:03 pm

hey tizxx......i dont think bidir or hybrid afects the problem....i just render an scene with bidir on and hybrid off....renders ok for 15 minutes....then i close the render and i restart them an oupsss all is black.....with some wheti dot here and there....i think some randomnes with this problem....Onoooooooooooooooo

tizxx · Post by **tizxx** » Wed May 02, 2007 2:48 am

Now If we use Diffuse materials insteat PHONG Materials

there is no problem.

BIDIRECTIONAL + HYBRID MODE with diffuse materials
is more quick than no bidirectional and no hybrid.

Hybrid mode is physically correct solution?
Bidirectional mode is physically correct solution?

If we turn toghether off we have a physical correct solution...

Kosmokrator · Post by **Kosmokrator** » Wed May 02, 2007 3:01 am

i dont realy know....ana he says there is a bug with bump map tha couses the black images but here u have any bump?i think no....so...im confused...i hope Ono fix this strange situation!

tizxx · Post by **tizxx** » Wed May 02, 2007 3:03 am

The wood plane has a little bump map

Kosmokrator · Post by **Kosmokrator** » Wed May 02, 2007 3:08 am

hhmmm try to remove anu bump map and make the test again...i think this is the litle devil

Kram1032 · Post by **Kram1032** » Wed May 02, 2007 4:25 am

Bidirectional is faster for caustics and indirect light.
Hybrid is faster for direct light.
The final result, however everytime should be simmilar.

tizxx · Post by **tizxx** » Wed May 02, 2007 4:43 am

this is without bump mup
All materials are of PHONG type
works fine...

Kosmokrator · Post by **Kosmokrator** » Wed May 02, 2007 5:00 am

and about hybrid?is enabled? the bidir? i thin tha bump is the problem as mention Ono....

tizxx · Post by **tizxx** » Wed May 02, 2007 5:14 am

Yes all is turned on

BIDIRECTIONAL
METROPOLIS
HYBRID

only the materials are withouut bump map and PHONG type...

I wait 40 minutes, because in previous images
after max 10 minute the image change radically

We wait news from Ono...

I like very much this wonderful render-engine.

Kram1032 · Post by **Kram1032** » Wed May 02, 2007 6:06 am

you increased the exponent, right?
I like it, looks good

F.ip2 · Post by **F.ip2** » Wed May 02, 2007 9:43 am

this hybrid, bidir path, mtl talk makes me dizzy.

is it possible that maybe somebody smarter than me
might write an explanation who those algorithm work
and when you should use the and why?

claas

manitwo · Post by **manitwo** » Wed May 02, 2007 10:18 am

all modes should give the exact same image after a given time. So every mode is physical accurate. The difference between those modes is how the noise converges. Some modes are faster, some slower for different things.

- MLT is good for indirect light, glass and caustics but not so good for direct light. Generally the noise is kind of "dirty-patchy-nonuniform".
- PathTracing is good for direct light but needs longer for indirect light, glass and caustics. The noise is uniform.
- Hybrid is a combination of MLT and PT. Hybrid uses PT for direct light and MLT for indirect light, glass and caustics. Hybrid combines the strenghts of MLT and PT. If Hybrid is enabled the Metropolis option is ignored.

- Bidir can be combined with MLT or PT or Hybrid. Bidir makes noise in scenes with indirect light, glass and caustics clear faster.
In indigo 0.8t1 bidir is causing black-image problems but keep in mind that the actual version is a test release! - so don't hesitate
- rQMC is (afaik) a more efficient way of sampling which also makes the noise clear faster (some scenes benefit a bit, others a lot). As a side effect there might be noise-"patterns" in the first seconds of rendering. rQMC is enabled since 0.8 - you cant turn it off - but why should you?

once again:
Possible Combinations:
- MLT Mode: ("Metropolis"-true)
- Pathtracing Mode: ("Metropolis"-false)
- Hybrid Mode: ("Hybrid"-true)
- Bidir MLT Mode: ("Metropolis"-true, "Bidir"-true)
- Bidir Pathtracing: ("Metropolis"-false, "Bidir"-true)
- Bidir Hybrid Mode: ("Hybrid"-true, "Bidir"-true)

The last two modes are recommend.

Hope this helps!

Indigo 0.8 test 1

Who is online