Multi-attribute edit

[davidhatten]

It would be cool if users could adjust attributes together. Easiest use case I can imagine is grabbing the inner and outer radius of something and moving them both at the same time to keep the shape the same but just change position.

Doing this within a single shape would be useful and reasonable. Doing this across shapes would be really neat but a UX nightmare to figure out. Maybe just start with single shapes and figure out cross-shapes if someone asks