So, not technically Glowforge-specific, but a dandy tool for people who work in Photoshop:
As of the CC 2018 Update, Photoshop now has a super sweet symmetry painting tool built in. If you go to Edit> Preferences> Technology Previews, there’s a box you can check for “Paint Symmetry.” Once you’ve done that, you’ll now see a little butterfly icon in your paintbrush tools, with a selection of available symmetries to use. Being in the “previews”, this feature is still sorta in beta I suppose, so it’s not exhaustive and some of the options are a little silly, but it’s still really fun to play with.
I spent some time doodling with it last night
I hope they’ll add some radial symmetry and other options down the road.
And yeah yeah, I know, Corel has had this forever. Shush!