icon - Effectively creating this effect in Illustrator?

Been lurking awhile but this is my first post.

I've always wondered what this effect is called and I'm almost certain there's an easier way to doing it than how I do it. I'm talking about the "empty" stroke around overlapping parts of icons.

In this case I would put a stroke that's the color of the background around the first character. I know this is bad practice for many reasons, but I haven't found a way to use the pathfinder to do this.

I'm looking for a way to do it that would effectively cut away the shapes smoothly in a X amount of pixels around a certain shape instead of covering it up so I can save the icon and use it over whatever colored background I want to.

I'm guessing I'm not the first person to ask this but I have no earthly clue how this effect is called so my research has returned nothing relevant.

Answer

This is most effectively achieved by offsetting the path of the front shape, and subtracting the resulting shape from all the shapes in the back, using the Pathfinder.

As an example, say I'd like to do the outlining with the blue shape as my front shape:

• Select the blue shape with the Move tool (V);


• Choose Object > Path > Offset Path...;


• Key in an amount. The preview option will help you with this.

This will leave you with just the enlarged version of your object selected, so you can continue:

• Edit > Copy the currently selected (enlarged) shape. Ctrl/Option+C works too of course;


• Edit > Paste in Front (Ctrl / Option+F) as many times as you have objects in the back you need to trim;


• Select one of the copies and one of your background object (use Shift+Click to add to a selection), then Subtract in the Pathfinder palette (second option);

• Repeat for all objects in the background;


• You should be left with one instance of your enlarged shape. You can delete it, but I like to hide it, so I can re-use it later in case some more objects get added to the background.

Result: