No specular bounce / no Transparency shadow

HAWK12HT

Hi, Unity is PBR ready yet we dont have specular bounce lighting aka caustics.
So does this mean that its partial PBR / incorrect lighting since for metals (chrome) albedo is black and hence light bounced from this surface wont contribute in lighting at all.
Please correct me if I am wrong here, my aim is to create high end architectural vizualization and so far what ever links I have seen dont talk about this.
(will it be safe to say that for Unity faking light bounce is the way to go even with PBR)

Also any ideas or links on how to go on about making colored shadows inside Unity, like stained colored windows creating volumetric lighting and shadows at same time.

Farfarer

You probably want to add in some reflection probes for PBR reflections and lighting. I don't think it will do caustics, though.

Perhaps you could set up some temporary objects to emit light for the offline bakes, bit disabled in the runtime.

There's no easy way to get coloured shadows in like you're after. You could fake it with a light out projector that has a cookie?

Joopson

Accurate caustics are very difficult, and aren't a part of any real-time lighting system I've heard of. PBR really has very little to do with Global Illumination or Caustics; it's more about maintaining accurate interactions between the Albedo, Roughness, and Specular, with the conservation of energy.

Faking caustics is probably the way to go; but, honestly, in most cases, it's probably safe to leave out caustics. It's really not that often that you see, in a way that's strong enough to truly discern, caustics in daily life.

You could render out some caustic-pattern alphas in an offline renderer, and use them as your light function (not sure what it's called in Unity, though. Basically, instead of the regular round-ish light area, you import an alpha, and the light will show up based on that.) Most noticeable caustics basically follow between 3 and 5 patterns, so it wouldn't be too tough, I don't think.