Object ID to a whole group

Question

How to add an index ID to thousand of objects?

Selecting the whole group and changing the ID, It applies only to the singular object..

a solution could be to assign a different material and so to use that index.. but what about objects IDs?

Answer 1

Here's how you do it:

1. Select all the objects you want to change
2. For the active object (last one selected), change the Pass Index to the Index ID you want.
3. Right click on the Pass Index field and select "Copy to Selected" from the menu

All the objects should now be updated to the same index ID.