My nomination for the ‘most useful ever’ tool in Adobe Illustrator is, of course, the Pathfinder. Here’s a guide to which tool does what, as well as some suggestions on how they can be useful as you draw.
Please note: If you wish to duplicate this tutorial, make sure you click on the ‘expand’ button after using each Pathfinder tool. The screenshots shown here have all been expanded in order to show what is happening to the shapes clearly in outline view.
Add to Shape Area (or ‘Unite’ in CS4)
This tool is pretty self explanatory: It will take shapes and merge them together. Select the shapes you want to merge, click on the ‘Add to Shape Area’ button, and click ‘expand’. Voila, it’s now one shape.
Note that the shapes don’t have to be overlapping, either. This function can come in handy if you’ve drawn a pattern: Use ‘Add to Shape Area’ on all same colored objects, and it’s easier to change their colors.
Subtract from Shape Area (or ‘Minus Front’ in CS4)
Another easy to use tool. This will punch out any shape you select in the shape of the object on top of it. This one is great to use if you’re cleaning up objects hanging off your artboard, of if you want a specific area cut out of an object.
Intersect Shape Areas (or ‘Intersect’ in CS4)
This will take any shapes and delete areas where they do not overlap. Say you’re drawing a shape and then adding shading to it: copy the shape, select the shading, and use this function to clean up all the excess areas.
Exclude Overlapping Shape Areas (or ‘Exclude’ in CS4)
This tool does the opposite of the ‘Intersect’ function. It will take any overlapping shapes and remove the area where they overlap each other.
The Divide function will take any shapes selected and cut them into separate pieces, kind of like a cookie cutter. The screenshot shown here shows the pieces moved away from each other: You can see that the area where the star and circle overlapped each other is now a separate editable shape.
Be careful with this tool. Always copy your shapes onto a new layer before applying, in case you need to go back to the originals!
Trim is a great tool for cleanup. As you can see in the example, any areas where shapes overlap will be deleted. This tool is useful if you have a lot of unnecessary overlapping objects.
This tool is similar to ‘Add to Shape Area’, except that it will preserve the appearance of the objects you are applying it to. It’s also very similar to the ‘Trim’ function above. The ‘merge’ tool also has another handy use: It will close open shapes for you with just one click.
The crop tool will take two shapes and delete the portions of where the bottom shape doesn’t overlap the top shape. This is a great asset when shading objects: You don’t have to be precise when drawing your shading outside your main shape. Just use ‘Crop’ to quickly trim the shape exactly where you want it trimmed.
This tool will take all selected shapes and break them into separate outlined objects.
The Minus Back tool will punch a background shape out of any foreground shape. This is similar to the ‘Crop’ tool, except the entire background object will be removed.
© 2009 Jennifer Borton