I initially brought this up in the 3.06 Release thread but I thought I better follow it it up here as the more I look into this it seems as though it might be something done by design (or I'm just being an idiot) and I didn't want to bog down the thread with something that wasn't relevant to the release.
I have a problem with rendering shadows from 2 objects which have the same ID but more specifically it seems to only be a problem when the objects are on top of each other or close enough to cast shadows onto each other. For example in this image, the sphere is on top of a plane and they both have ID number 2 but the shadow pass comes out empty:
However in this attachment, I again have two objects (two spheres) which share the same ID number (ID #2) and this time I have turned off the ID for the plane. This actually does allow me to render shadows for two objects together with the same ID as they are both on top of the plane but still doesn't give me a solution for exporting the plane shadows together with the spheres without a second render:
Finally I used the exact same ID set up as the last image (both spheres set to #2 and no ID for the plane) and put the spheres on top of each other. Notice that the same thing happens as when I put a sphere onto a plane and set both their IDs to the same number. The two spheres don't receive any shadows and the only thing receiving shadows is the plane as it is the only object excluded from the Render Layer selection.
To me it looks as though if a Render Layer is set to cast shadows, that layer is then excluded from receiving shadows. This causes problems if both objects you wish to included in the same ID number are casting shadows onto each other and you want to get both of those objects shadows in a single pass.
I'm sure there is a simple reason for this but is there a way around this at all?
Thanks!
Kraig.
