Shadow Terminator problem

Discussion related to the Engine functionality, implementations and API.
Racleborg
Posts: 525
Joined: Sat Apr 07, 2018 10:31 am
Location: UK

Re: Shadow Terminator problem

Post by Racleborg » Mon Aug 12, 2019 6:03 pm

by Dade » Sat Aug 10, 2019 3:32 pm
Racleborg wrote: ↑
Fri Aug 09, 2019 6:21 pm
I am not sure if this is relevant to the currently discussed Bump issue, but I don't appear to be getting any Bump effect be with the Checkerboard Texture like it does with other textures such as Distorted Noise?
This should be normal: the bump is proportional to the difference of 2 adjacent pixels, if the pixels have the same color (like inside a check), there is no difference and the normal is unmodified. So it is modified only on the sharp edge between 2 checks.
Thank you for the explanation

User avatar
lacilaci
Donor
Posts: 1642
Joined: Fri May 04, 2018 5:16 am

Re: Shadow Terminator problem

Post by lacilaci » Mon Aug 19, 2019 8:42 am

demonstration of the problem on a simple plane and weak bump

bump
bump.jpg
no bump
nobump.jpg
file
bump.blend
(532.22 KiB) Downloaded 17 times

User avatar
Dade
Developer
Posts: 3362
Joined: Mon Dec 04, 2017 8:36 pm
Location: Italy

Re: Shadow Terminator problem

Post by Dade » Tue Aug 20, 2019 9:02 am

provisory wrote:
Sun Aug 11, 2019 9:27 am
After some comparisons I think again, that something is not perfect with LuxCore bump mapping.

Left side is highly subdivided and has displacement modifier with the bump texture.
Right side is low poly and has bump mapping with the same bump texture.

Cycles:
bump-test3-cycles.jpg


LuxCore after shadow terminator taming:
bump-test3-luxcore_new.jpg


LuxCore before it:
bump-test3-luxcore_old.jpg
I should have fixed the problem, this is a rendering before the fix:

old.jpg

and this after the fix:

new.jpg

Extreme bump scale values are now handled far better, this was before:

old2.jpg

and this after the fix:

new2.jpg
Support LuxCoreRender project with salts and bounties

User avatar
lacilaci
Donor
Posts: 1642
Joined: Fri May 04, 2018 5:16 am

Re: Shadow Terminator problem

Post by lacilaci » Tue Aug 20, 2019 9:07 am

Dade wrote:
Tue Aug 20, 2019 9:02 am
provisory wrote:
Sun Aug 11, 2019 9:27 am
After some comparisons I think again, that something is not perfect with LuxCore bump mapping.

Left side is highly subdivided and has displacement modifier with the bump texture.
Right side is low poly and has bump mapping with the same bump texture.

Cycles:
bump-test3-cycles.jpg


LuxCore after shadow terminator taming:
bump-test3-luxcore_new.jpg


LuxCore before it:
bump-test3-luxcore_old.jpg
I should have fixed the problem, this is a rendering before the fix:


old.jpg


and this after the fix:


new.jpg


Extreme bump scale values are now handled far better, this was before:


old2.jpg


and this after the fix:


new2.jpg
This looks fantastic, how about long flat planes with bump, won't they look like they collect dust?

Image


will give this a go as soon as it's "cooked"

User avatar
Dade
Developer
Posts: 3362
Joined: Mon Dec 04, 2017 8:36 pm
Location: Italy

Re: Shadow Terminator problem

Post by Dade » Tue Aug 20, 2019 9:12 am

lacilaci wrote:
Tue Aug 20, 2019 9:07 am
This looks fantastic, how about long flat planes with bump, won't they look like they collect dust?
Your test scene seems to work fine with the new version:

plane.jpg
Support LuxCoreRender project with salts and bounties

User avatar
lacilaci
Donor
Posts: 1642
Joined: Fri May 04, 2018 5:16 am

Re: Shadow Terminator problem

Post by lacilaci » Tue Aug 20, 2019 9:21 am

Dade wrote:
Tue Aug 20, 2019 9:12 am
lacilaci wrote:
Tue Aug 20, 2019 9:07 am
This looks fantastic, how about long flat planes with bump, won't they look like they collect dust?
Your test scene seems to work fine with the new version:


plane.jpg
Amazing, thanks!

provisory
Posts: 224
Joined: Wed Aug 01, 2018 4:26 pm

Re: Shadow Terminator problem

Post by provisory » Tue Aug 20, 2019 9:22 am

Dade wrote:
Tue Aug 20, 2019 9:02 am
I should have fixed the problem...
Looks good, thank you!

(I'm away from my computer for a few days. I'll test it when I'm back.)

tokiop
Posts: 17
Joined: Fri Apr 13, 2018 8:11 pm

Re: Shadow Terminator problem

Post by tokiop » Tue Aug 20, 2019 1:07 pm

Nice result and collaboration, thanks both for your investment !

User avatar
lacilaci
Donor
Posts: 1642
Joined: Fri May 04, 2018 5:16 am

Re: Shadow Terminator problem

Post by lacilaci » Wed Aug 21, 2019 5:07 am

Just to confirm, both shadow terminator fix and bump mapping is now working excelently and in 2.81 daily build! Perfect!

provisory
Posts: 224
Joined: Wed Aug 01, 2018 4:26 pm

Re: Shadow Terminator problem

Post by provisory » Thu Aug 22, 2019 12:50 pm

I made some tests, and I also think it works nicely.

...except the problem with the translucent materials:
http://forums.luxcorerender.org/viewtop ... f=4&t=1325

Post Reply