Another issue,
I started testing pgi on my office scene and I'm seeing a lot of reflections being cut short...
I've noticed this happening in every scene.
Only way to fix this seems to be using very high Usage threshold scale.
For example, lookup radius 10cm and usage threshold scale of 6 was used in the rendering.
To fix the reflection problem I had to use usage threshold scale of 16 (I only tried the fix on crop render so I don't know what's the performance penalty of using higher usage threshold)
PhotonGI cache
Re: PhotonGI cache
What does this threshold do?
I feel we will need a good troubleshooting guide to use this feature.
I feel we will need a good troubleshooting guide to use this feature.
Re: PhotonGI cache
The scene (attached) crashes every time with PGI on, and any scene I create with a MIX material like this, also crashes.
Thank you
Thank you
- Attachments
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- Mix Fail.blend
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Re: PhotonGI cache
Surprisingly, it looks like the problem is in the geometry. First of all, it renders fine on the CPU while the problem is visible in OpenCL. This is because the (mysterious) reduced precision of the OpenCL code. If you check the geometry, you will see the object has 1 back face overlapped with the wall face (and there is a "Z fight" even inside Blender shaded view port). Than the front face is very near the back face. Deleting the back face and making an hole in wall face (so it is not near the front face) should fix the problem.
Re: PhotonGI cache
It may be exactly the opposite: floor will start to "borrow" light form perpendicular walls using a 90 deg angle so the image will start to gain too much light (instead of loosing them when using a 10deg angle).
This seems also suggested by the reference rendering with plain path tracing: https://github.com/LuxCoreRender/LuxCor ... erence.png
It is darker, not brighter.
Re: PhotonGI cache
Just leave the default parameters and mark the material of the floor as "not cached". It will fix the problem with a barely noticeable impact on rendering time.lacilaci wrote: ↑Sat Feb 23, 2019 8:58 am I started testing pgi on my office scene and I'm seeing a lot of reflections being cut short...
I've noticed this happening in every scene.
Only way to fix this seems to be using very high Usage threshold scale.
For example, lookup radius 10cm and usage threshold scale of 6 was used in the rendering.
To fix the reflection problem I had to use usage threshold scale of 16 (I only tried the fix on crop render so I don't know what's the performance penalty of using higher usage threshold)
Have you changed the default glossiness threshold ? I ask because looking at the floor, I'm quite sure it has a roughness lower than 0.2 (i.e. it is nearly a mirror).
Re: PhotonGI cache
Yes I did use glossines threshold at 0.0
Probably not a good idea.
Probably not a good idea.
Re: PhotonGI cache
This is somewhat expected, your scene includes a single cube and the material roughness is under 0.2 so it is marked as "cache disabled". So you entire scene doesn't include a single surface where cache is enabled and PhotonGI is useless.
I have modified the code so it will print a big "WARNING" for this case and will proceed rendering with normal path tracing.
Re: PhotonGI cache
I'm getting exactly the same rendering (caustic aside) out of PathOCL+PhotonGI:epilectrolytics wrote: ↑Thu Feb 21, 2019 6:30 pm Another visualisation of the problem the caustic cache has with infinite background light:
Took B.Y.O.B.'s dice file and replaced the area light with white background color:
(latest builds including photon merge, from Blender)
test.jpg
and PathOCL:
I'm using this light source:
Code: Select all
scene.lights.distl.type = distant
scene.lights.distl.color = 1.0 1.0 1.0
scene.lights.distl.gain = 10 10 10
scene.lights.distl.direction = 1 1 -1
Re: PhotonGI cache
I assume epilectrolytics is using a constantinfinite light.