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Raytraced translucency flickering

raytraced translucency + large plane + camera near parallel with plane = a lot of flickering (even with fully opaque and rough material!)

https://i.imgur.com/myofNVe.gif

I got this with 4.25 and it’s still happening on 4.26 preview, the only workaround I figured was switching to raster translucency…

is there some other workaround how to avoid flickering and keep raytraced translucency?

Was this solved? If so, how?

No, there’s no solution (AFAIK).
Everytime you make a large plane and want to use raytraced translucency you will get this type of flickering. This is present even in 4.26p4.

Large scales seem to be a big problem for raytracing in general. Maybe not even a bug but rather a precission error and since there are no controls over this I would assume it’s not solvable on user end.

I think that is it, a precision error. I was reading a paper on ray tracing, and watched an old NVidia video about it, and one of the primary challenges in ray tracing is precision. It’s not efficient to continuously trace a massive number of rays from every possible source to every possible target (e.g., surface to surface reflection), so mathematical formulae are used to functionally get a similar / same result with a limited number of traced rays. It’s probably a problem with tracing rays from the camera to a certain distance from the camera at ‘parallel’ type angles because the formulas used are not sufficient to complete the render. Is the water + reflections on it in games like Battlefield V and Star Wars Battlefront 2 done via ray tracing? If so, I wonder whether the flickering occurred to those initially, and how it was resolved.