Ring self shadowing

[JonasGilg]

Rings have now shading on the dark side based on transparency:

[coveralls]

Pull Request Test Coverage Report for Build 2690370622

• 0 of 10 (0.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.002%) to 2.993%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
plugins/csp-rings/src/Ring.cpp	0	10	0.0%
<!--	Total:	0	10	0.0%	-->

Totals
Change from base Build 2614742148:	-0.002%
Covered Lines:	491
Relevant Lines:	16403

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💛 - Coveralls

[Schneegans]

Awesome! Have you tested this in VR? The computation of the lit side looks a bit as if it could go wrong there :wink:

[JonasGilg]

I tried the following functions for the dark ring side. At the bottom is a reference image. I am not quite happy with any of them, but I think for a real solution we need a much more complex approach with scattering calculations.

	No HDR	HDR (default)	HDR (-3.5 compensation)
1-a
(1-a)^2
-sqrt(a)+1
1-a^2

Reference:

[JonasGilg]

I tested it on the power wall in VR and it works. You can even see the light side with one eye and the dark side with the other.