Create a clipping mask in ArcGIS Online's Map Viewer

Highlighting your map’s area of interest is often job one for a map. If not job one, then at least job three or four. And that’s still a pretty high priority. Here’s how you can trick an unsuspecting group of layers into becoming a clipping mask in the ArcGIS Online Map Viewer…

No time for videos? I get it. Here’s the rundown…

• Pick a basemap (this will be what appears as your not-area-of-interest)
• Add your interest layer
• Add a layer whose shape you want to use as a clipping mask (cookie cutter)
• Group the interest layer and the clipping layer, with the clipping layer on top
• Give the clipping layer a Destination Atop blend mode
• Profit

Check out this blog post from Bern Szukalski that goes into a lot more detail and provides more examples and use cases.

Are you more programmatically inclined? The geniuses on the ArcGIS for JavaScript show you how to do it that way in this code sample. Whichever way you prefer, you will be masking and clipping and area-of-interesting your way right to the top.

Happy Masking! John