1/ caustic cache isn't animation proof.epilectrolytics wrote: ↑Wed Dec 23, 2020 10:34 am BiDir was never a valid ground truth renderer because of the missing SDS reflections, except when using intersectable lights and rendering for 24 hours.
When this problem finally gets solved by adding PGI cache it is very welcome.
No one is forced to use this addition, it can be disabled by default.
The question is if PGI really will resolve all missing paths or only a subset like it does when used with hybrid path?
BiDirVM does render all kinds of reflected caustics, including those from indirect light, in reasonable time, but it is broken currently.
If caustic cache can be set up to do the same that would be a great advantage for everyone interested in realistic physically based rendering, no matter the additional parameters. It is quite possible that a default set-up will cover most cases.
2/ if you try it in many cases you will notice that a default setup is nearly impossible
3/ we already use it in path tracing so we are not against it (i have myself multiple tutorial on the topic)
4/ What we are discussing is philosophy behind each mode Bidir vs Path + LC + PGI.
5/ The alternative we propose is more futur proof / animation capable while following the Bidir minimal setting approach..
Seriously do you think you will be able to use cached caustics if there was a one click solution like the one in Light tracing ??