Dissolve/fade a shadow


#1

From what I can tell, shadows are either “on” or “off” and cannot be made to fade proportionally as an object fades. This is consistent with transparent objects casting solid shadows - presumably because the system is casting shadows, not ray tracing them. This is a problem when fading out an object since the shadow pop on or off.

Is this correct? If so, does anybody have any ideals of how I might fake a shadow fade? I’ve tried adjusting the timing of when a shadow pops on or off, and that helps a little bit in masking the “pop.” But I’d like to do better if I can.

Thanks!


#2

Hi @wturber

That’s correct, shadows are ‘all or nothing’.

It is possible to get the effect of fading out a light’s shadows as follows. Create a duplicate of the light in question, but with shadows disabled and intensity 0. When fade time comes you increase the shadow-less light intensity from 0->1 while simultaneously decreasing the shadow-casting light intensity from 1->0.


#3

Thanks for the confirmation. Yes, we thought about crossfading lights, but there are other items in the scene that aren’t fading and they would lose their shadows as well - which is something we don’t want. What we need would be for lights to be assignable to specific objects and not others.