Siggraph 2012 Luxrender - Need user feedback SPPM

[guibou]

Hi,

I'm really pleased to announce you that we will be part of a Siggraph presentation at Los Angeles this summer.

I'll have a 15 minutes talk about LuxRender and our implementation of Density Estimation (ie. photons) methods. I'll mainly focus on SPPM implementation detail.

I also want to give users feedback about SPPM method and for this I need your contribution.

Mainly I want to know:

- Are you using SPPM for your work and why ?
- If no, why ?
- What kind of work are you doing with it. Is this hobby, are you in a small art company, are you part of a big company ?
- What are for you the pro and cons of the method ?
- What can be improved ?

Be sure that the audience will be high level researchers, so they may be interested on any feedback about issues you have (you, people from real life which uses their work).

Thank you very much for your feedbacks. I also want to thank every people involved in sending me to this talk, especially Dade which was initially the person contacted to do the talk.

[SATtva]

Great news!

I also want to give users feedback about SPPM method and for this I need your contribution.

With ease:

- Are you using SPPM for your work and why ?

I do. There are situations when it provides results faster and better than Bidir, especially when i can sacrifice sharp caustics.

- What kind of work are you doing with it. Is this hobby, are you in a small art company, are you part of a big company ?

I'm a freelance 3d designer/visualizer.

- What are for you the pro and cons of the method ?

(Considering particular SPPM implementation in Lux.) Pros: Fast convergence in scenes involving complex lightpaths -- interiors, many specular interactions; very easy to configure compared to classic PM. Cons: Heavy memory requirements for hires images; no participating media support; some peculiarities with multilobe glossy materials.

- What can be improved ?

Lower memory footprint and light scattering support would be of the most importance to me. Also it sometimes happens that on the final stages of rendering a bright photon color spot lands somewhere, spoiling the whole image as it gets reflected/refracted in all objects. If that can be somehow mitigated, it would be really nice.

[neroe23[TheOne]]

- Are you using SPPM for your work and why ?

Yep, because I like to work with latest technologies, especially for eye-candy and it can produce very complex caustics of caustics which other algorithm cannot (bi-dir, am I right ?).

Code: Select all

- What kind of work are you doing with it. Is this hobby, are you in a small art company, are you part of a big company ?

3d modeling is a free-time activity because as a high school student I don't have much time for this. So definitely Hobby.

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- What are for you the pro and cons of the method ?

Pro: caustics are rendered quickly and converge nicely. Con: no light scattering, so no dusty air for dramatic scenes.

Code: Select all

- What can be improved ?

Uh implement light scattering as SATva said ?

As I am NOT a great artist NOR an IT engineer, any of my previous statement might be false. Feel free to delete anything stupid correct me.

PS: Heck yes ! I use to watch anything new from SIGGRAPH on youtube so if any video is published give us the link !!

[Abel]

I'm really pleased to announce you that we will be part of a Siggraph presentation at Los Angeles this summer.

Nice, congratulations!

- Are you using SPPM for your work and why ?
- If no, why ?

I don't; I use LuxRender for its ease of use and don't want to have to think about what settings to use, and also because of how realistic it is. Furthermore SPPM feels like it is still under heavy development, I'd rather have other people be the guinea pigs. In situations where I have to render faster, I typically use another renderer (VRay)

- What kind of work are you doing with it. Is this hobby, are you in a small art company, are you part of a big company ?

Architectural visualisation, at a mid-sized architecture firm and for own and freelance projects.

- What are for you the pro and cons of the method ?
- What can be improved ?

Can't tell yet, I hope to try it soon.

[Meelis]

Hi

I havent really used the SPPM much, but the speed is really impressive and as i have read in forum (even for the scattering when it's gonna be implimented).
And the SPEED is really what i'm waiting for scattering medium.

http://vimeo.com/30727270

[giuliojiang]

- Are you using SPPM for your work and why ? Yes, I did some experimentation and I really liked SPPM...
- If no, why ? ... but sometimes didn't use it because it needs a lot of ram (especially with many lightgroups) and sometimes it's a bit unpredictable
- What kind of work are you doing with it. Is this hobby, are you in a small art company, are you part of a big company ? I'm doing works just for hobby
- What are for you the pro and cons of the method ? Pro: quite fast with very complex lighting situations. Cons: I have only 4GB ram, and I can't use SPPM for some works. Maybe some bugs, but I believe they'll be fixed quickly
- What can be improved ? I think, nothing. I just noticed that some default settings of the blender exporter are not ideal.

[J the Ninja]

- Are you using SPPM for your work and why ?
- If no, why ?

At the moment, no. The memory requirement for high-resolution images is still very large, due to storing hit points for every pixel. Behavior with glossy materials still seems unpredictable. (will it screw it up, or won't it??!!! )

- What kind of work are you doing with it. Is this hobby, are you in a small art company, are you part of a big company ?

I use LuxRender for personal projects, we use Maya/Mental Ray at work.

- What are for you the pro and cons of the method ?

Pros: Much harder to "throw it off" with complex lights, particularly lights shining into a reflector or behind objects/fixtures. Cons: glossy things, also no volumetric scattering support means it's a no-go any time you need dusty air, SSS, murky water, etc.

- What can be improved ?

Reduced memory usage, perhaps by allowing to only store hit points from a subset of pixels. Also, volumetric support and more sane configuration of starting radius. (I still have no clue how it comes up with the radius it does).

[A-man]

- Are you using SPPM for your work and why ?
- If no, why ?

I use it quite a bit. I find it produces good enough results for material testing very quickly (usually in under 2 or 3 minutes). The 'biasedness' of it I guess is to thank for this, but it really helps not having to wait an hour just to see if the material looks good.

- What kind of work are you doing with it. Is this hobby, are you in a small art company, are you part of a big company ?

I'm just a hobbyist. I'm trying to hone my skills though, so I could perhaps get into the profession later on in life.

- What are for you the pro and cons of the method ?

Pros: Very fast overall. Complex light paths seem trivial for it.
Cons: glossy materials don't work properly, no participating media. There was an interesting paper on this somewhere in the forums, I can't seem to find it. Memory usage is pretty high, but it is tolerable for anyone with a decent amount of RAM.

- What can be improved ?

Participating media support would do it for me, as well as fixing glossy surfaces.

[J the Ninja]

Cons: glossy materials don't work properly, no participating media. There was an interesting paper on this somewhere in the forums, I can't seem to find it. Memory usage is pretty high, but it is tolerable for anyone with a decent amount of RAM.

This one? viewtopic.php?f=8&t=5525&p=75151#p75116

[A-man]

This one? viewtopic.php?f=8&t=5525&p=75151#p75116

That's the one! Thanks for the keen eyes there JtheNinja