Illustrator - Subtract a group from another group

Question

I have two groups, one of which contains about 30 black "compound path" objects, and another of which contains about 150 white mixed shapes. I want to subtract the black objects from the white objects, so I've put the black on top. I selected both and chose "minus front" from the pathfinder window, but this yields "no results" according to adobe.

What would be the best way for me to go about subtracting this group of objects from the second group of objects? When I make the white objects a compound path it yields unwanted overlap, so I would prefer to not have to make my white objects their own compound path, and I also can't individually convert 150 objects to their own individual compound path.

What is my best solution here?

Answer 1

Pathfinder's "Minus Front" works on single objects, you simply can't use it on groups.

A few options:

1. Turn each group in to a compound path. The overlapping path issues is (I assume) just a path direction issue. You can simply hit one of the path direction buttons in the Attributes panel with you compound path selected to correct it.

   

2. Pathfinder "Unite" each group first. You can hold alt while hitting the Unite button to create a compound shape from the Pathfinder result instead of the normal destructive output—this essentially works exactly the same as creating a compound path but without the overlapping path issues.

3. A better option is probably to use Pathfinder's "Merge"—which should combine everything of a similar fill color and remove anything below. Simply hit "Merge" and delete the resulting black areas, leaving only the combined white shapes. This relies on each group being entirely a single color though.