Indigo OpenCL the fastest PB Renderer out there?

General questions about Indigo, the scene format, rendering etc...
User avatar
Silverwing
Posts: 68
Joined: Sun Aug 23, 2015 1:16 am
Location: Ludwigsburg Germany
Contact:

Re: Indigo OpenCL the fastest PB Renderer out there?

Post by Silverwing » Sun Jan 15, 2017 4:42 am

zeitmeister wrote:Why does it look more realistic? It looks more homogenous, but is that realistic?
That indeed is very true.
There was a kind of similar thread some time ago on CG-Society. And someone stated there that unless you have a real world example to compare it to it it sort of impossible to say whats realistic.

Oscar J wrote:Interesting comparisons.

Rendering a glossy transparent object in a uniform environment is a good way to make sure they follow the laws of energy conservation. As you can see Indigo (CPU) renders the glossy transparent monkey pretty much exactly homogeneously with the uniform background. As does Maxwell, after a very long rendering time, at least fairly close.

I agree with zeit that I don't think the Maxwell one looks more realistic. To compare apples to apples you should probably compare Indigo CPU with Maxwell CPU though, as Indigo CPU has virtually infinite path depth, while the limited path depth of Indigo GPU probably affects its appearance (see the darker edges in your render). Would also be interesting to see how Maxwell GPU compares.
Thanks a lot for the comparison. This is something that was on my agenda too.
P.s. I should have mentioned that I did a bunch of test behind the curtains. Also including comparing Indigo CPU to Indigo GPU. As Zom-B states further down. While CPU is a tid brighter besides that there is no difference in look (definitely the same algorithm was used for both CPU aswell GPU.

I can do a render with Maxwell GPU. Due to the really narrow ray depth (of 8 as stated above) it definitely will look different. I consider Maxwell GPU to be in sort of alpha stage at the moment. Indigos GPU progress is way ahead here.

Zom-B wrote:Exactamundo!
In the provided scene we have a lightsource from the left, the frosty dragon could act like a magnifying glass and bundle the light from that side.
Here a long CPU rendering of that dragon (20kspp), where you see that its even brighter then on GPU!
Thanks a lot for your test! I have attached some more below to further fuel the discussion :-)

About Realism:
As stated above. Without a real world sample or "example" to match it against is impossible to tell.
I think the reaction that Maxwell is more realistic comes from the following fact:
The rougher the glass the more rays get diffused (dispersed). The more rays get diffused (when entering and also when leaving the material) the more uniform it will look because to form a magnifying lens effect you need rays that are more parallel rather then rays that travel in a very chaotic manner.

I am however not saying that Indigo is unrealistic. Since shaders represent an "assumption" on the surface structure both maxwell and indigo might be correct dependent on the treatment of the glass surface maybe.

I will edit this post later this evening with some more tests:
The dragon renders with 0, 0.25, 0.5, 0.75, 1 roughness.
For Indigo CPU, GPU and Maxwell CPU, GPU
You don´t dream in cryo.

User avatar
Zom-B
1st Place 100
Posts: 4635
Joined: Tue Jul 04, 2006 4:18 pm
Location: ´'`\_(ò_Ó)_/´'`
Contact:

Re: Indigo OpenCL the fastest PB Renderer out there?

Post by Zom-B » Sun Jan 15, 2017 6:39 am

Silverwing wrote:Without a real world sample or "example" to match it against is impossible to tell.
You could simplify this whole setup down to a light + sphere for example:
sphere.zip
(49.28 KiB) Downloaded 65 times
Here you see that bundling of light I was referring to for the dragon, in this simplified case its even understandable that a part of the light that exists as caustics, do exit at the sphere due to the rough surface as rays that also hit the camera and therefore brightens up that area...
Attachments
sphere.png
polygonmanufaktur.de

User avatar
Silverwing
Posts: 68
Joined: Sun Aug 23, 2015 1:16 am
Location: Ludwigsburg Germany
Contact:

Re: Indigo OpenCL the fastest PB Renderer out there?

Post by Silverwing » Sun Jan 15, 2017 10:08 am

Zom-B wrote:
Silverwing wrote:Without a real world sample or "example" to match it against is impossible to tell.
You could simplify this whole setup down to a light + sphere for example:
The attachment sphere.zip is no longer available
Here you see that bundling of light I was referring to for the dragon, in this simplified case its even understandable that a part of the light that exists as caustics, do exit at the sphere due to the rough surface as rays that also hit the camera and therefore brightens up that area...
Yes I understand.
This behavior is plausible up to a certain roughness. At some point the rays that enter the sphere might get so dispersed that they fly in all possible directions rather then focus on the back end of the sphere.

There is something else I noticed. While Indigo OpenCL has 16 refractive bounces while using specular material. It only has 8 refractive bounces when using the glossy material.
Ray_Depth_Indigo_GPU_Specular.jpg
Indigo GPU OpenCL has a ray depth of 16 when it comes to specular refraction
Ray_Depth_Indigo_GPU_Glossy.jpg
Indigo GPU OpenCL has a ray depth of 8 when it comes to glossy refraction


Also Maxwell GPU goes haywire when rendering rough transparent objects.
You clearly can see that in the charts:


Indigo roughness scale CPU:
Indigo 01 - RD1000 - CPU BiDir - Rough 0.00.jpg
Indigo 01 - RD1000 - CPU BiDir - Rough 0.25.jpg
Indigo 01 - RD1000 - CPU BiDir - Rough 0.50.jpg
Indigo 01 - RD1000 - CPU BiDir - Rough 0.75.jpg
Indigo 01 - RD1000 - CPU BiDir - Rough 1.00.jpg

Indigo roughness scale GPU:
Indigo 01 - RD1000 - GPU PT - Rough 0.00.jpg
Indigo 01 - RD1000 - GPU PT - Rough 0.25.jpg
Indigo 01 - RD1000 - GPU PT - Rough 0.50.jpg
Indigo 01 - RD1000 - GPU PT - Rough 0.75.jpg
Indigo 01 - RD1000 - GPU PT - Rough 1.jpg

Maxwell roughness scale CPU:
Maxwell 01 - RD1000 - CPU BiDir - Rough 00.jpg
Maxwell 01 - RD1000 - CPU BiDir - Rough 25.jpg
Maxwell 01 - RD1000 - CPU BiDir - Rough 50.jpg
Maxwell 01 - RD1000 - CPU BiDir - Rough 75.jpg
Maxwell 01 - RD1000 - CPU BiDir - Rough 100.jpg

Maxwell roughness scale GPU:
Maxwell 01 - RD1000 - GPU PT - Rough 00.jpg
Maxwell 01 - RD1000 - GPU PT - Rough 25.jpg
Overbright... something is clearly wrong here.
You don´t dream in cryo.

User avatar
Oscar J
1st Place Winner
Posts: 2163
Joined: Sat Mar 31, 2012 3:47 am
Location: Gothenburg, Sweden
3D Software: Blender

Re: Indigo OpenCL the fastest PB Renderer out there?

Post by Oscar J » Sun Jan 15, 2017 10:33 am

I stand corrected actually, I think Indigos glossy transp looks a bit odd at high roughness. Maybe its glossy transp model doesn't behave as realistically at such extreme roughness values. Would be interesting to hear a devs response on this.

User avatar
Zom-B
1st Place 100
Posts: 4635
Joined: Tue Jul 04, 2006 4:18 pm
Location: ´'`\_(ò_Ó)_/´'`
Contact:

Re: Indigo OpenCL the fastest PB Renderer out there?

Post by Zom-B » Sun Jan 15, 2017 10:37 am

Oscar J wrote:I stand corrected actually, I think Indigos glossy transp looks a bit odd at high roughness. Maybe its glossy transp model doesn't behave as realistically at such extreme roughness values. Would be interesting to hear a devs response on this.
This might me due to the zero absorption of the base colour here. All incoming light also trespasses the object and exits it, that is maybe not common in real life... just a suggestion!
polygonmanufaktur.de

nmeau
Posts: 30
Joined: Sun Aug 21, 2016 11:14 am

Re: Indigo OpenCL the fastest PB Renderer out there?

Post by nmeau » Tue Jan 17, 2017 9:41 am

I'm in over my head on this discussion but there seems to be an issue with Glossy Transparent on GPU that's been noted before. See the 0.47 thread.

SharpEars
Posts: 4
Joined: Thu Jan 12, 2017 4:07 am

Re: Indigo OpenCL the fastest PB Renderer out there?

Post by SharpEars » Thu Jan 19, 2017 8:27 am

At 0 roughness, the Maxwell CPU rendering looks far more realistic than the Indigo CPU one, based on my experience looking at lit glass/acrylic sculptures. There is more detail present and the low contrast gradations look far more realistic. I see lots of blown-out highlights in the Indigo CPU version that Maxwell renders with subtlety and finesse.
Last edited by SharpEars on Thu Jan 19, 2017 10:24 am, edited 1 time in total.

User avatar
Oscar J
1st Place Winner
Posts: 2163
Joined: Sat Mar 31, 2012 3:47 am
Location: Gothenburg, Sweden
3D Software: Blender

Re: Indigo OpenCL the fastest PB Renderer out there?

Post by Oscar J » Thu Jan 19, 2017 8:36 am

SharpEars wrote:At 0 roughness, the Maxwell CPU rendering looks far more realistic than the Indigo CPU one, based on my experience looking at lit glass/acrylic sculptures. There is more detail present and the low contrast gradations look far more realistic. I see lots of blown-out highlights in the Indigo CPU version that Maxwell renders with subtlety and gradations.
Maxwell fanboy spotted. :) But yeah, I'm inclined to agree, maybe a material bug in Indigo.

burnin
Posts: 114
Joined: Tue May 04, 2010 2:53 pm

Re: Indigo OpenCL the fastest PB Renderer out there?

Post by burnin » Thu Jan 19, 2017 1:49 pm

SharpEars wrote:At 0 roughness, the Maxwell CPU rendering looks far more realistic than the Indigo CPU one, based on my experience looking at lit glass/acrylic sculptures. There is more detail present and the low contrast gradations look far more realistic. I see lots of blown-out highlights in the Indigo CPU version that Maxwell renders with subtlety and finesse.
Maxwell, ah... yeah, ok... am still on v3, following the v4 development...
But check another 'thingy':

Image
source @ corona forums

About cycles glass shader (even with multiscatter GGX), that's really not an apple anymore - unidirPT, no special options, acceleration/optimizations for caustics (just check shadows under the glossy glass or read more here)... so unless anyone is willing to render forever as ie. Cycles: Caustics & the noise... no need to bother, use it artistically (use tricks)

Surprisingly Iray glass and caustics rendering gives quite fast results but surface isn't looking that convincing...
Still some hope is left for RCs Arion & SIs Thea if they have some ace left up their sleeve with further development...
Silence before the storm or a dry & windy winter then long moist & humid summer... hell, no. :D

PS
momentarily forgot about PIXARs RMan - there's something hidden inside ;)

still waiting on a day when a physically accurate rainbow will be rendered in real time :P

Eneen
Posts: 165
Joined: Thu Jan 21, 2016 9:32 am

Re: Indigo OpenCL the fastest PB Renderer out there?

Post by Eneen » Thu Jan 19, 2017 8:41 pm

SharpEars wrote:At 0 roughness, the Maxwell CPU rendering looks far more realistic than the Indigo CPU one, based on my experience looking at lit glass/acrylic sculptures. There is more detail present and the low contrast gradations look far more realistic. I see lots of blown-out highlights in the Indigo CPU version that Maxwell renders with subtlety and finesse.
Besides little sharpness (you can't disable dof in indigo) and exposure I really can't see difference... Indeed between Indigo PT and MX bidir difference is huge, but between these two...?

http://www.indigorenderer.com/forum/dow ... &mode=view
http://www.indigorenderer.com/forum/dow ... &mode=view

Eneen
Posts: 165
Joined: Thu Jan 21, 2016 9:32 am

Re: Indigo OpenCL the fastest PB Renderer out there?

Post by Eneen » Thu Jan 19, 2017 9:08 pm

burnin wrote:PS
momentarily forgot about PIXARs RMan - there's something hidden inside ;)
Isn't that similar to Photon mapping extensions that Indigo will have:
http://www.indigorenderer.com/indigo3.8
(scroll to bottom)

User avatar
thesquirell
Posts: 380
Joined: Fri Aug 29, 2014 3:49 am
Location: Novi Sad, Serbia

Re: Indigo OpenCL the fastest PB Renderer out there?

Post by thesquirell » Thu Jan 19, 2017 9:37 pm

Eneen wrote:
SharpEars wrote:At 0 roughness, the Maxwell CPU rendering looks far more realistic than the Indigo CPU one, based on my experience looking at lit glass/acrylic sculptures. There is more detail present and the low contrast gradations look far more realistic. I see lots of blown-out highlights in the Indigo CPU version that Maxwell renders with subtlety and finesse.
Besides little sharpness (you can't disable dof in indigo) and exposure I really can't see difference... Indeed between Indigo PT and MX bidir difference is huge, but between these two...?

http://www.indigorenderer.com/forum/dow ... &mode=view
http://www.indigorenderer.com/forum/dow ... &mode=view

Agreed. And, might I add, Maxwell's sharpness actually looks less realistic to me. It's just my personal taste, but Indigo's render looks much more smoother, all around, polished, enjoyable then Maxwell's. As for the caustics on the ground, I'm not gonna say anything about that, judge it by yourself. Actually, I am: Indigo's are two levels higher, more accurate, and faster then Maxwell's.

User avatar
Originalplan®
Posts: 733
Joined: Sat Sep 26, 2015 8:58 pm
3D Software: Cinema 4D
Contact:

Re: Indigo OpenCL the fastest PB Renderer out there?

Post by Originalplan® » Thu Jan 19, 2017 10:14 pm

Eneen wrote:
SharpEars wrote:At 0 roughness, the Maxwell CPU rendering looks far more realistic than the Indigo CPU one, based on my experience looking at lit glass/acrylic sculptures. There is more detail present and the low contrast gradations look far more realistic. I see lots of blown-out highlights in the Indigo CPU version that Maxwell renders with subtlety and finesse.
Besides little sharpness (you can't disable dof in indigo) and exposure I really can't see difference... Indeed between Indigo PT and MX bidir difference is huge, but between these two...?

http://www.indigorenderer.com/forum/dow ... &mode=view
http://www.indigorenderer.com/forum/dow ... &mode=view
Actually i think the DOF should be there..considering the scene is 50 mm.
And i really like it makes it more realistic to me. But if you change cam settings you should be able to turn it OFF or at least make it not so present/direct....like on a real camera.

All things considered...Maxwell is nice....on CPU.
But Indigo....oh boy 8) 8) 8) 8) i like it much more especially when i think about measured materials etc.

Eneen
Posts: 165
Joined: Thu Jan 21, 2016 9:32 am

Re: Indigo OpenCL the fastest PB Renderer out there?

Post by Eneen » Thu Jan 19, 2017 11:20 pm

Originalplan® wrote: Actually i think the DOF should be there..considering the scene is 50 mm.
And i really like it makes it more realistic to me. But if you change cam settings you should be able to turn it OFF or at least make it not so present/direct....like on a real camera.

All things considered...Maxwell is nice....on CPU.
But Indigo....oh boy 8) 8) 8) 8) i like it much more especially when i think about measured materials etc.
Sure, with DOF it looks better.
@Silwerwing has chosen pinhole camera that turns of DOF completely so Maxwell have speed advantage here too.

burnin
Posts: 114
Joined: Tue May 04, 2010 2:53 pm

Re: Indigo OpenCL the fastest PB Renderer out there?

Post by burnin » Thu Jan 19, 2017 11:39 pm

Eneen wrote:
burnin wrote:PS
momentarily forgot about PIXARs RMan - there's something hidden inside ;)
Isn't that similar to Photon mapping extensions that Indigo will have:
http://www.indigorenderer.com/indigo3.8
(scroll to bottom)
I don't know in detail, but the great difference is it's intended use - for volumetrics & SSS.
Maybe someone knowledgeable with the Indigo internals could chime in... :wink:

Papers on which the RMan integration is based upon:
"Unifying Points, Beams, and Paths in Volumetric Light Transport Simulation"
J. Křivánek, I. Georgiev, T. Hachisuka, P. Vévoda, M. Šik, D. Nowrouzezahrai, and W. Jarosz
ACM Transactions on Graphics (SIGGRAPH 2014), 2014
(Unified formulation of Monte Carlo path integration and photon density estimation with points and beams)
>> source <<

Post Reply
46 posts

Who is online

Users browsing this forum: No registered users and 1 guest