Annoying, Ugly Shadow Lines

[TyrannoWright]

After the issue of the colored shadows, I'm getting these lines in the shadows that make some characters look ugly and textures seem annoying along with a framerate drop.

[RobertBeckebans]

Yeah it is the typical shadow mapping acne problem. I couldn't get around
this problem yet.

2015-07-22 23:07 GMT+02:00 TyrannWright notifications@github.com:

After the issue of the colored shadows, I'm getting these lines in the
shadows that make some characters look ugly and textures seem annoying
along with a framerate drop.

[image: rbdoom3bfg exe_2015-07-22-21-05-07-387]
https://cloud.githubusercontent.com/assets/10506744/8837361/daf612a8-307a-11e5-921d-c060e70218ca.jpg
[image: rbdoom3bfg exe_2015-07-22-21-06-06-556]
https://cloud.githubusercontent.com/assets/10506744/8837365/e005a9d4-307a-11e5-99b9-0165aee4275f.jpg

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#237.

[TyrannoWright]

Shame. Let's hope for a fix soon...
Edit: I also found some areas in maps to have black patches. I would think this is also the acne problem.

[nbohr1more]

Maybe fixable?

#203

[ghost]

@TyrannWright I've noticed that BFG seems to have an issue with gamma correction, often colorizing the textures with purple/green tints which is why things seem a bit off, the only way around it is by setting custom gamma settings in the graphics card driver control panel.

@RobertBeckebans This artifact also appears in Blender's game engine when using shadows, usually improved when using the variance method and increasing the raycast length as well as sample resolution. Not sure if it is the same for the soft shadows you've written.

[RobertBeckebans]

Found something interesting that might help: http://www.dissidentlogic.com/old/images/NormalOffsetShadows/GDC_Poster_NormalOffset.png

[ghost]

Interesting. Near the end of the article, they spoke of post process filtering. Maybe a cheap blur on the shadow pass?

[QcSamuel]

any news on this ?

[Calinou]

I suppose shadow bias could be increased in the meantime. This will cause shadows to "peter-pan" noticeably around their caster though.

[QcSamuel]

i wonder if the completed vulkan renderer could fix this ?

[Calinou]

i wonder if the completed vulkan renderer could fix this ?

Vulkan doesn't resolve this in itself. This can also be fixed in an OpenGL renderer by implementing shadow normal offset bias as mentioned above.

[RobertBeckebans]

This has been fixed in the new DX12 / Vulkan backends using temporal anti aliasing.