Finding Your Way — with Pathfinder
Contributed by Brenda Sutherland, Illustrator Team Rowing Captain
Several years ago I used to teach Beginning Illustrator at a local Jr. College. When we would get to the section on Pathfinder my students would look at the following diagram and and experience two very strong emotions. First was excitement as they realized with a single click of a button they could combine or divide objects into new shapes. The second was immediate intimidation over the number of buttons, the mysterious icons, and the fear that they would never master them all.
“Relax” I’d tell them. “You don’t need to memorize them all. Just remember that it’s possible! As long as you know there is a way, you can experiment until you get it right. That’s what Undo is for!”
So why is this tool so important? What’s the big deal? Let me explain. You know that Illustrator provides a lot of shape tools. You have your basic circles and squares, which can also create ovals and rectangles, then there’s the star tool and the polygon tool which can create objects with various points and sides, there’s even a rounded rectangle tool, line tool and a grid tool. But it doesn’t matter how many tools we provide. There will always be shapes that you need to create that won’t be possible with any single tool. For example, if you wanted to create a key. There’s no “Key Tool” in illustrator, and even if there was, it probably wouldn’t create exactly the right key for you anyway.
Pathfinder is a powerhouse for creating and editing shapes. The Pathfinder Panel allows you to access this functionality directly, and other features, such as Live Paint and the Blob Brush use Pathfinder as the underlying technology to combine and merge objects as well.Here is a very simple illustration to show how some simple shapes can be combined to create a single object.The Pathfinder panel can create paths, compound paths, and compound shapes. When we first introduced compound shapes in Illustrator 10 we changed Pathfinder’s default behavior so that the shape buttons would create sompound shapes by default, and holding down the Option (Mac) or Alt (Win) key while pressing a shape button would expand the compound shape into a compound path. Since then we heard from many users that they either were confused about compound shapes, or they were expanding them to compound paths when they created them. So in CS4 we switched the functionality so that the Pathfinder panel creates compound paths by default now and the modifier key is used to create compound shapes.So what’s the difference? What are the advantages of one over the other? I think David Cross does a great job describing the Pathfinder panel functionality in this tutorial from Layers Magazine.But please note, David did this tutorial in CS2, and while all the information he covers is also true in CS4, the default behavior was changed so now you are creating compound paths by default and using Option/Alt for compound shapes.Still curious about what compound shapes are? Teri Pettit, who has been deep in the code of Illustrator for over two decades, has posted a great reference to help describe how compound shapes work. Teri’s post was made prior to CS4, so in order to use the compound shape functionality of adding and subtracting to objects, you will need to use the modifer keys.As I mentioned earlier, Pathfinder is also the underlying technology behind many other features in Illustrator. We’ll go into more detail on these in future blogs. In the meantime, step forth without fear! Work with Pathfinder to create new, interesting shapes and see how you like working with compound paths vs. compound shapes.