translucent ray-trace shadows on opaque objs

[PhasmaCeritus]

hi,

I was wondering if it is possible to make direct light ray-trace self shadows decay after each pass through surface while surface is completely opaque.

I have done it with depth maps by setting my obj's opacity to .5 pre-rendering shadow map and using that map on the same object with opacity value 1.

Could anybody suggest how it could be done with ray-traced shadows? Examples would be totally awesome

Thanks!

[brianburke]

I have done it with depth maps by setting my obj's opacity to .5 pre-rendering shadow map and using that map on the same object with opacity value 1.

not quite sure what the purpose of this is, but here's how you would achieve this gag using raytrace shadows

its pretty chill

[PhasmaCeritus]

not quite sure what the purpose of this is, but here's how you would achieve this gag using raytrace shadows

its pretty chill

total awesomeness

thanks Brian.

well for example I am using it to fake SSS on tree leaves. I took care of the color and now shadow is also decaying with each pass through a leaf...

but taking this further in therms of efficiency I was thinking how to limit this effect to a certain penetration level since opacity approach slows down ray-tracer a lot. Lets say switching opacity to 1 after 5th pass.

or getting the same effect without modifying opacity I am not sure if its possible but maybe by multiplying shadow intensity with each pass...? or I am just talking about the same thing since shadow ray still have to travel further after hitting opaque surface?

Edited December 31, 2010 by PhasmaCeritus