Cycles Manifold Next Event Estimation #94120

New Issue

Brecht Van Lommel · 2021-12-15T18:37:06+01:00

Brecht Van Lommel commented

2021-12-15 18:37:06 +01:00

Short term:

Initial implementation D13533: Adding Manifold Next Event Estimation Sampling Technique
Solve potential issues with motion blur
Walk without relying on UV maps for consistent directions
Metal GPU support
Separate MNEE code from shade_surface kernel somehow, running before or after?
Separate shader ray-tracing and MNEE versions of shade_surface kernel?

Longer term:

Extend to more general specular manifold sampling, for reflective caustics
Integrate with path guiding

Short term: - [x] Initial implementation [D13533: Adding Manifold Next Event Estimation Sampling Technique](https://archive.blender.org/developer/D13533) - [x] Solve potential issues with motion blur - [x] Walk without relying on UV maps for consistent directions - [x] Metal GPU support - [ ] Separate MNEE code from `shade_surface` kernel somehow, running before or after? - [ ] Separate shader ray-tracing and MNEE versions of `shade_surface` kernel? Longer term: - [ ] Extend to more general specular manifold sampling, for reflective caustics - [ ] Integrate with path guiding

Brecht Van Lommel commented

2021-12-15 18:37:06 +01:00

Changed status from 'Needs Triage' to: 'Confirmed'

Brecht Van Lommel commented

2021-12-15 18:37:06 +01:00

Added subscriber: @brecht

Brecht Van Lommel commented

2022-04-01 16:32:34 +02:00

Added subscriber: @olivier.fx

Raimund Klink commented

2022-04-01 18:05:04 +02:00

Added subscriber: @Raimund58

Arthur F commented

2022-04-01 19:14:54 +02:00

Added subscriber: @S1ft

Alaska commented

2022-04-02 02:13:18 +02:00

Added subscriber: @Alaska

Olivier Maury commented

2022-04-05 00:13:27 +02:00

A bit of consolidation, adding references to:
#96990: MNEE caustics with Multiscatter GGX materials are inconsistent.
#96991: MNEE does not fall back to alternative caustic technique when MNEE does not work.
#96992: MNEE caustics are treated as "direct light" when they should be "indirect light".
#97056: MNEE caustics don't render with specific materials when Filter Glossy = 0
#97054: Caustics Shadows Artifacts

A bit of consolidation, adding references to: #96990: MNEE caustics with Multiscatter GGX materials are inconsistent. #96991: MNEE does not fall back to alternative caustic technique when MNEE does not work. #96992: MNEE caustics are treated as "direct light" when they should be "indirect light". #97056: MNEE caustics don't render with specific materials when Filter Glossy = 0 #97054: Caustics Shadows Artifacts

Aditya Y Jeppu commented

2022-04-14 20:44:16 +02:00

Added subscriber: @quantimoney

Aditya Y Jeppu commented

2022-04-14 20:44:16 +02:00

Was testing the shadow caustics. Noticed that for some reason, the viewport render is able to show me the caustics perfectly, but actually rendering an image out disregards any form of special caustics. Any idea why this is happening? The surprising thing is for certain cases the caustics gets rendered into output correctly, but in other cases, only parts have the caustics in scene.

This might be just a case of complexity in the scene thats causing the issue, but irrespective of that, if its able to show me a clear image in the viewport (after waiting for the samples to run), then it should show me the same when rendering output. Adding this comment here, can create task later if its general issue, and not something wrong with personal file.

(private work, cannot send actual file here, therefore attaching screenshots)

viewport realtime view (this has a sky texture for lighting, using just a sun lamp also gives this issue, but localised area lighting sometimes works, sometimes does half of those shadow rays seen in image)

render output

Was testing the shadow caustics. Noticed that for some reason, the viewport render is able to show me the caustics perfectly, but actually rendering an image out disregards any form of special caustics. Any idea why this is happening? The surprising thing is for certain cases the caustics gets rendered into output correctly, but in other cases, only parts have the caustics in scene. This might be just a case of complexity in the scene thats causing the issue, but irrespective of that, if its able to show me a clear image in the viewport (after waiting for the samples to run), then it should show me the same when rendering output. Adding this comment here, can create task later if its general issue, and not something wrong with personal file. (private work, cannot send actual file here, therefore attaching screenshots) viewport realtime view (this has a sky texture for lighting, using just a sun lamp also gives this issue, but localised area lighting sometimes works, sometimes does half of those shadow rays seen in image) ![viewport.png](https://archive.blender.org/developer/F13001811/viewport.png) render output ![render_output.png](https://archive.blender.org/developer/F13001813/render_output.png)

makizar commented

2022-04-17 23:26:23 +02:00

Added subscriber: @makizar

Olivier Maury commented

2022-04-22 02:30:17 +02:00

Thanks for reporting this @quantimoney, I can't really explain why you would see a difference between viewport and render, could you maybe post a simple scene showing this behavior (one of the windows for example)? Do you have render only modifiers that could alter the mesh in any way? Thanks!

blender-admin commented

2022-04-22 18:25:18 +02:00

This issue was referenced by 58be9708bf

This issue was referenced by 58be9708bfa069df2db7415a64ec76c3fc012868

Brecht Van Lommel added this to the Render & Cycles project 2023-02-07 19:08:06 +01:00

Philipp Oeser removed the

Download

What's New

Blender Studio

Manual

Developers Blog

Documentation

Benchmark

Blender Conference

Development Fund

One-time Donations

Cycles Manifold Next Event Estimation #94120