
Casual Shadertoy Path Tracing 2: Image Improvement and Glossy Reflections - Impossible
https://blog.demofox.org/2020/06/06/casual-shadertoy-path-tracing-2-image-improvement-and-glossy-reflections
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dang
Part 1 was discussed here:
[https://news.ycombinator.com/item?id=23308054](https://news.ycombinator.com/item?id=23308054)

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fallingfrog
On the subject of the blue and magenta ball- I’ve seen materials that look
like that in the real world, it was a specially coated mirror, I can’t
remember what we used it for, but we were doing laser based imaging of live
cells. If you held the mirror at the right angle you could see that the light
transmitted was one color and the light reflected was another color.

Update: it’s called a dichroic mirror:
[https://en.m.wikipedia.org/wiki/Dichroic_filter](https://en.m.wikipedia.org/wiki/Dichroic_filter)

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fizixer
part 1: [https://blog.demofox.org/2020/05/25/casual-shadertoy-path-
tr...](https://blog.demofox.org/2020/05/25/casual-shadertoy-path-
tracing-1-basic-camera-diffuse-emissive/)

You started part 1 with:

> When you see a photorealistic image that someone says is “ray traced” what
> they likely mean is that it is “path traced” ...

well, you just became my new hero. Thank you for saying what is my pet peeve
ever since nVidia started using the term ray tracing for some stupid reason
that I will never understand.

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kaoD
Isn't path tracing a subset of ray tracing?

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NikosVitsas
I would see it’s the other way around. A path is definitely a more generic
term than a ray.

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viscoelastic
However paths are made out of rays. So the basic technology implemented on the
GPU is to calculate intersections or rays against geometry, raytracing, which
is the basic building block of path tracing and several other classes of
algorithms.

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navaati
Oh, I loved the first article, super happy there is a follow-up !

