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Sharp corners looking smooth

Posted: Sun Nov 03, 2019 11:24 am
by AndreKR
I attached a scene I made.

There are some sharp corners that look smooth in Lux:
2019-11-03-12-18-38-blender.png
The same area in Cycles:
2019-11-03-12-19-32-blender.png
This area also looks weird (there's also a shadow terminator issue here, but that's not what I mean):
2019-11-03-12-21-59-blender.png
Cycles:
2019-11-03-12-23-04-blender.png
What is going on?

Re: Sharp corners looking smooth

Posted: Sun Nov 03, 2019 1:47 pm
by Racleborg
Maybe Lux isn't seeing the MARK SHARPs :?:

Re: Sharp corners looking smooth

Posted: Sun Nov 03, 2019 1:53 pm
by B.Y.O.B.
BlendLuxCore supports Blender's auto smooth, but it does not support custom normals. I have not looked at the file yet, but maybe you are using custom normals?
Maybe Lux isn't seeing the MARK SHARPs
Mark sharp works if used with autosmooth or the edge split modifier.

Re: Sharp corners looking smooth

Posted: Sun Nov 03, 2019 3:36 pm
by B.Y.O.B.
At the moment, you have to clear the custom split normal data to have a working mesh in Lux.
In a quick test it seems to fix the problem, however I don't know what this data was needed for exactly, so you will have to consider if this model works without the custom normals.
It is planned to implement this feature eventually.

Re: Sharp corners looking smooth

Posted: Sun Nov 03, 2019 3:59 pm
by AndreKR
Wow, thanks, I would have never found that myself.

I imported the mesh from an .obj that I made in MoI, so this "custom split normals data" is apparently something that comes from the .obj importer. Removing it seems to have no effect on the mesh.

Re: Sharp corners looking smooth

Posted: Sun Nov 03, 2019 4:31 pm
by AndreKR
Could LuxCoreRender maybe just ignore this data? Because it seems it has to be cleared manually for every object. :|

Re: Sharp corners looking smooth

Posted: Sun Nov 03, 2019 5:30 pm
by B.Y.O.B.
We are currently ignoring it, and this is the result we get.
So I fear the answer is no, Blender skrews with the mesh data in some way and ignoring doesn't help.