When you create vector illustrations to sell on stock sites such as GraphicRiver, your file must be compliant with several technical requirements. One of the requirements states that there should be no open paths in your file. But nobody tells you why. In this article, I'll show you why open paths can be a problem, how to find and close open paths, and how to avoid them in the first place.
Why Do We Care About Open Paths?
Why does anybody care about open paths? Normally, when you're creating a vector illustration, that's the last thing on your mind. You just want it to look good. As long as the file prints or exports fine, that's OK, right? Well sure, but when you're selling that same vector on GraphicRiver, you have to remember that buyers may want to edit it to suit their own needs. And this is when open paths can be a problem. Let's look at some examples.
The Squares below are identical, except for the Stroke Weight. Both shapes are open, because I cut the path at the lower right corner, using the Scissors Tool. You can see that as the Stroke Weight increases, the open path becomes apparent. If a buyer wanted to increase the Stroke Weight on a path — and that path was open – they might get some unexpected results.
Some effects don't work as expected when you have an open path. In the image below, the square on the left is closed, and the one on the right is open. A Rounded Corner effect has been applied to both objects. Since the path on the right is open, there is no corner to round.
Here, the Offset Path effect has been applied to each object. You can see that on the open path, the Offset effect gets applied to both the inside and outside of the path, because it is not closed.
Some path operations simply do not work on open shapes. Many of the Pathfinder functions will not produce results, and some of the items under the Object > Path menu will return an error message if you try to use them. In the example below, the Split Into Grid function cannot be used on an open path:
So those are some examples of why stock sites do not allow open paths. You must remember that all kinds of people will be downloading your files and some of them will want to modify them or edit them in some way. Closing paths prevents unexpected results.
Are There Exceptions to the Rule?
There is an exception to the open paths rule. Open shapes that are unfilled are okay. That is, any path that has a stroke color but no fill color can remain open. Here is an example where it makes sense to leave the strokes open. In the original illustration the notebook paper lines are 0.25 point thick, which is just about the smallest that will print. If a designer decides to scale down the illustration, those lines may become unprintable. Leaving them as strokes lets the designer easily adjust the Stroke Weight. If those paths had been turned into closed, filled rectangles, scaling them would be a lot more work. So again, keep the buyer in mind when choosing to leave unfilled paths open.
Important note to designers: In Adobe Illustrator, be sure to check "Scale Strokes & Effects" in your Preferences. That way, when you enlarge or reduce an illustration, the strokes will scale proportionally.
Finding Open Paths Before You Upload
You should always check for open paths before uploading your files. The easiest way to find open paths is to use the free Select Menu plug-in by Graffix Software. After installing the plug-in, go to Select > Object and choose Open Paths (better yet, assign a keyboard shortcut to it) and all of the open paths will be selected. The plug-in won't distinguish between filled and non-filled paths, it just shows you where they are.
Select Menu is great (it has a lot of other useful features, and it's free!), but it doesn't necessarily select all of the open paths. If any open paths are locked or hidden, the plug-in won't select them. Also, ruler guides are actually open paths, but the plug-in won't select those for you either. (Guides won't get your file rejected, but it's a good idea to delete them before submitting, just so novice users won't be confused by them.)
The one iron-clad, fail-safe way to know whether there are open paths in your file is to use the Document Info panel (Window > Document Info) in Illustrator. Here you will see a wealth of information about your file, including the number of paths, closed and open. Click the fly-out menu on the panel, then check "Objects" and uncheck "Selection Only" to see the whole file at a glance.
If you're having difficulty tracking down the open path(s), you can use a process of elimination, using the Document Info panel. First, re-check "Selection Only." Then select an object or layer in the file. If the panel shows that all paths are closed, hide those then move on to the next selection. And remember to delete the guides.
How to Close Open Paths
If you just have a few simple open shapes, you can use the Pathfinder Add/Unite function to close them. Just remember to select them one at a time - you don't want to merge them all together!
There are also a few scripts out there, as well as plug-ins that feature a "close paths" command. But you can actually use the Knife Tool (the one with the separated edge, underneath the Scissors Tool), then drag a circle around your objects or entire illustration. Filled shapes will close; paths with a fill of "none" will remain open. Easy!
Preventing Open Paths
There are several things that will cause open paths even though you think they shouldn't. And this often happens after saving your native AI file to EPS v.8 or 10. These will vary depending your version of Illustrator, but they include:
- Simplifying a closed path (Object > Path > Simplify) will sometimes make it open.
- Flattening transparency. In addition to other problems, flattening transparent effects can cause open paths.
- Aligning a stroke to the inside or outside of a shape in the Stroke panel. This is an appearance attribute, so when you save as EPS, it expands it, which can result in an open path.
- Same goes for adding strokes via the Appearance panel. Expanding the appearance can cause open paths.
- Custom brush strokes. In older versions of Illustrator, when you expand a custom brush stroke, the "spine" is left behind. It is an open path and can be deleted.
Knowing what to look for when creating vector illustrations and logos will help prevent open paths. The best thing you can do to avoid an open path rejection is to save your EPS, close it, then reopen it and check again. It’s an extra step, but it beats having to re-submit.
Suggested work flow for finding open paths:
- Create your logo or illustration. Save early and often, in native AI format.
- Unlock all objects (Object > Unlock All). Show all objects (Object > Show All).
- Zoom way out to see any stray shapes outside the artboard.
- Check Document Info panel for open paths. If none, skip to step 8.
- Run the plug-in to find open paths.
- Close paths that require closing.
- Check Document Info again. Look for transparency, symbols, patterns, etc. that may need expanding.
- Save file as version 10 EPS.
- Close and re-open the EPS file, then check for open paths again. If open, filled paths are found, return to step 2. If not, go to step 10.