I don’t know about you, but I have a love/hate relationship with Illustrator’s pathfinder tool (Window > Pathfinder). I love that it makes my job easier in cases where I need to merge some shapes together or separate overlapping shapes. However, if you are anything like me, you probably have no idea what each one of those buttons do and often find yourself trying several before you get the result you want. Let’s end this once and for all by taking a comprehensive look at each button in the pathfinder tool window.
Before I get into each button on the Pathfinder window, it is important to note that there are two different series of buttons. The top row are called “Shape Modes” while the bottom row are called “Pathfinders.” In addition, you will find the “Expand” button as well which is normally only activated after you have created something using one of the following buttons.
The “Unite” button is the first button on the left under the “Shape Modes” series of buttons. This button is probably the easiest to use and the easiest to understand. Just as its name suggests, it is meant to unite, or combine two or more shapes to make a new shape.
In my example above, I have two shapes that I would like to combine into one vector shape: the red oval and the green oval. Selecting both of these shapes and clicking the “Unite” button, they now become one shape (the green shape on the right). For this particular case, the new shape takes the color of the shape that was on top.
The next button under “Shape Modes” is called “Minus Front.” Just like the name implies, it is designed to take away whatever the top shape covers on the bottom shape away from the bottom shape. In older versions of Illustrator, this may actually be called “subtract from shape,” but I think the new name (at least in CS5) is easier to understand.
The image above shows just that. I took the same red and green ovals and using the “Minus Front” button, it took away from the red oval what the green oval was covering. I find this button useful when I want to take one shape out of another shape. I simply put the shape I want to cut out on top of the shape I want it cut out of, click the “Minus Front” button and now I have one shape with the shape cut out of it nice and neat.
Third in line is called the “Intersect” button. The idea behind this button is to find the intersecting lines and create a shape from the overlapping areas. In other words, it leaves you with only with only the part that is overlapping another part.
This button tends to work best when you have a small number of shapes. You will also find that certain placements will give you an error message saying nothing can be produced. Depending on the outcome you want, you may have to do two shapes at a time to produce the desired results. I find this button difficult to use for anymore than two simple shapes unless all the shapes overlap the same area.
The last of the “Shape Modes” series conclude with the “Exclude” button, which as you can image does exactly the opposite of the “Intersect” button. It will take out the overlapping area, leaving you with everything else.
Unlike its “Intersect” button counterpart, this does work with multiple shapes and even shapes that are overlapping three or more deep. However, when you have overlapping shapes or layers that is three layers deep, it will do the exclude twice (or one for each overlapping shape). This can either produce a really neat effect, but more than likely is not the effect you desire. It may take a couple of times to get the desired shape.
The first of the “Pathfinders” buttons is called “Divide.” Just as the name implies, it will divide all of the overlapping shapes into distinct, non-overlapping shapes. As you will find with most of the “Pathfinders” series buttons (those on the bottom row), it will produce similar results as the shape modes, however it is almost as it is a bit lazy in that it will not fully complete the job. When using this button, you can produce results similar to the “Minus Front,” “Intersect,” and “Exclude” buttons of the “Shape Modes” series.
You can see in the image above that I have one shape selected and you see the bounding box is over the area that was overlapping. When you use the “Divide” button, it counts that overlapping shape as its own shape. I said that most of the “Pathfinders” are basically lazy versons of the “Shape Modes” and this is a good example. It took each shape and make it its own, however it looks exactly the same as it did before. If you were to use “Exclude” it would have removed the shape I have selected in the image above.
The second “Pathfinders” button is “Trim.” This is very similar to the “Minus Front” shape mode, without actually removing the shape in front. This option will trim away from the bottom shape what the top shape overlaps, while leaving the top shape. The end result will be no overlapping shapes and the bottom shape having any overlapping areas removed.
Again, you can’t immediately see what it did without going and investigating. In the above image, I ungrouped the resulting shapes (it will create a group) and selected the shape that was trimmed so you can see. If I was to pull away the red oval right now from the green, it would have a missing section. Again, this is kind of the lazier version of “Minus Front.” I use this often to create “puzzle piece” shapes, where the desired result is to make the shapes look like they could interlock with each other.
This is where things start to get a bit more hairy. The “Merge” button (third from the left under “Pathfinders”) is picky in that it will merge the shapes that share the exact same styles, while trimming the under shapes using any overlapping shapes that do not meet the same style. Confused?
In the above image, it is a bit more clear. I added a second red oval and placed it on top of the two ovals I have used throughout this article (indicated by the yellow outline of the paths). Using the “Merge” button, it merged the two red ovals together (shown in the black outline of the paths) while using the green oval to trim the bottom red oval. Note that I pulled the green oval away from the shapes to help clarify what it did a bit better.
If your shapes are not using the same styles (you can see this in Window > Appearance), then the “Merge” button will revert to the “Trim” button. If you are using the same styles, then they will merge the shapes. The important thing to note here is that the bottom shape is what will be trimmed by anything that overlaps it on top that is not the same style as the bottom shape. This button is definitely one worth experimenting with to see what all it can do, as it is powerful, but can be confusing.
To the right of the “Merge” button is the “Crop” button. This is another one that behaves uniquely. When using the “Crop” button, it will take only the very top and very bottom shapes and create two new shapes. The two new shapes it creates depends on how they are overlapped. The resulting shape will be the very bottom shape that the very top shape overlapped, taking the styles of the very bottom shape. It also creates a second shape with no styles that is the very top shape with the new first shape cut out of it. I think this is best explained in a picture:
The picture shows what was cropped and what was left. The part that was “cropped” is the part that was overlapping, however it leaves the second shape as the very top shape, however trimmed away from the cropped shape. The new shapes will not be overlapping at all. Not sure how useful what I showed above would be, so below is a better, more useful representation of the “Crop” button:
In this example, I wanted everything inside of the red outlined box to be cropped to fit inside that box. With using what I described above, the “Crop” button took the very top shape (red box) and cropped everything below it to fit inside that box, while leaving what was the box as no fill and no shape, or “ghost” shapes. You can then take these individual shapes inside and take them out and move them as necessary.
The second from last of the “Pathfinders” series is called “Outline.” Unlike the other buttons above, it actually does not produce shapes at all. It will take each line segment and make it a path, using the fill color as the stroke color. Also, every time a path crosses another one, it automatically generates a new path, so that none of them are overlapping.
In the image above, it created exactly four paths, each with a stroke of the color that corresponded to the shape it is outlining. This is a great tool to use in conjunction with one of the other “Pathfinders” options in that you can create complex shapes then use the “Outline” button and create paths for those shapes. Using this button could lead to some unique and interesting outcomes.
The final button in the “Pathfinders” series is called “Minus Back.” It does exactly the opposite of what the “Minus Front” button in the “Shape Modes” series does: it takes the very bottom shape and removes the overlapping portion from the top shape.
Hopefully this will be a nice resource for you to turn to when you need to figure out how to create complex or intricate shapes and need a little extra hand. While some of us may not use all the buttons, each button has their unique use and can really help us out and be a time saver depending on the result that we want.