bidir vs pathocl Shading
Posted: Tue Aug 06, 2019 6:49 am
I've got some weird gradients going on with bidir, note the part on the top of the image...
bidir: pathOCL: blender file:
bidir: pathOCL: blender file:
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I have no access to my PC at the moment and cannot look at the object. This is why I ask a few questions.lacilaci wrote: Tue Aug 06, 2019 6:49 am I've got some weird gradients going on with bidir, note the part on the top of the image...
bidir:
bidirmetro_shading.jpg
pathOCL:
pathOCL_shading.jpg
blender file:
shading_issue.blend
Thanks, I'm aware how shading works. It would be kinda weird if I didn't by nowFarbigeWelt wrote: Tue Aug 06, 2019 7:06 amI have no access to my PC at the moment and cannot look at the object. This is why I ask a few questions.lacilaci wrote: Tue Aug 06, 2019 6:49 am I've got some weird gradients going on with bidir, note the part on the top of the image...
bidir:
bidirmetro_shading.jpg
pathOCL:
pathOCL_shading.jpg
blender file:
shading_issue.blend
Is the object smooth or flat shaded?
Do you see a gradient in solid openGL preview in viewport too?
If yes you can avoid this. Extrude top surface in edit mode. Move extruded surface a short way upwards (z-axis) just so that you can distinct vertices in top corners. The openGL shading should be uniform now. The render will be too.
I'm aware of this problem but I have yet to investigate the source, it must be something in MIS weights.lacilaci wrote: Tue Aug 06, 2019 6:49 am I've got some weird gradients going on with bidir, note the part on the top of the image...
Actually I did not expect anything else from someone with experienced skills.lacilaci wrote: Tue Aug 06, 2019 7:12 am
Thanks, I'm aware how shading works. It would be kinda weird if I didn't by nowit would also look the same in OCL rendering as in bidir if that was the case...
It's a simple flat plane, tried reseting normals, smoothing, flattening normals, reversing normals... and idk what else..
I have a feeling that you might have ran into a problem of custom normals in blender, where these are often not exported to luxcore and cause a LOT of trouble especially when you use CAD models or create custom breaks of normals in blender... very annoying but it just might be a blender bug/problemFarbigeWelt wrote: Tue Aug 06, 2019 9:48 amActually I did not expect anything else from someone with experienced skills.lacilaci wrote: Tue Aug 06, 2019 7:12 am
Thanks, I'm aware how shading works. It would be kinda weird if I didn't by nowit would also look the same in OCL rendering as in bidir if that was the case...
It's a simple flat plane, tried reseting normals, smoothing, flattening normals, reversing normals... and idk what else..But even close to perfection people forget sometimes the simplest things.
However, until yesterday I thought to know how Blender deals with surfaces and shading. What was that of an error! I have to post my latest observations this evening maybe someone of the forum has the explanations. There must be some hidden parameters of a triangle‘s surface which are independent on vertices and surface normal and these parameters are responsible for different smooth shading tones.![]()
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