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Hieron
11-04-2013, 08:07 AM
Suppose one has a scene full of partly transparent objects, all intermixed.
Now obviously all objects can be seen, partly, through eachother.
How could you adapt the surface, so that only the first surface is visible and all others are 100% transparent, non reflective, non spec etc.

For 1 surface type, it would be to just add logic nodes and above bounce 1 (Spot info) cut all to 100 and 0.

But now there are 2 surface types in the scene, both would need to show only the 1st one, all of similar type behind it need to be invisible.

Can't seem to figure this out.. anyone know how? (or even understands my convoluted question :))

Ideally there would not only be a bounce # info node, but also bounce # for a given surface. Does that exist?

Danner
11-04-2013, 08:57 AM
http://www.youtube.com/watch?v=nP425jM1oGM

Hieron
11-04-2013, 10:59 AM
yes but that is just (while nicely demonstrating normal perturbation) plain ol' simple bounce # based, as I said: "For 1 surface type, it would be to just add logic nodes and above bounce 1 (Spot info) cut all to 100 and 0." etc

Nothing specific to bounce #'s per specific surface.

Sensei
11-04-2013, 01:26 PM
Other surface is evaluated in completely different node editor, than previous bounce.. You can't have access to it, unless all surfaces are inside of global node editor.



How could you adapt the surface, so that only the first surface is visible and all others are 100% transparent, non reflective, non spec etc.

You could try making it in Global Materials http://globalmaterials.trueart.eu
Transparency is continuation of ray-tracing with ray origin at world spot, with same ray direction.

http://forums.newtek.com/attachment.php?attachmentid=117985&d=1383596647
http://forums.newtek.com/attachment.php?attachmentid=117984&d=1383596647
http://forums.newtek.com/attachment.php?attachmentid=117983&d=1383596647
http://forums.newtek.com/attachment.php?attachmentid=117982&d=1383596647

Hieron
11-04-2013, 02:53 PM
Hmm got to study this when my mind regains some IQ after sleep, but I think that it doesn't solve my specific issue. Can't be sure now though :) Nice example of global materials btw, thanks.

What I mean is a tad weird to explain. But imagine semi transparant glas tiles, each their own object (clone) of 2 base objects with their own surface. So, 2 objects, each 1 surface. Cloned many times.
Now, whenever a ray hits the first of one of the 2 surface types, it does x (basically show it), if it is the second or later, it does y (make sure it isn't seen).

The reason I need it (and have before) is that oftentimes you'd like to clip objects into eachother but not have it show the inside surface. This can be done by blocking ray refraction after bounce x ofcourse, but I still want to be able to see a deeper clipping, other surface.

Since this is ideally a generic setup, I prefer not to manually enter objects or surfaces etc. Just "skip the second of a kind", sort of...