Github, everyone’s favorite nerdery, added STL object file support – basically a system for uploading and rendering 3D models – in April. Now, however, they’ve improved their service with a system for finding the differences in subsequent versions of these 3D files, essentially adding an undo button to 3D modeling.
The system, as demonstrated here, takes two or more STL files and overlays them, allowing you to see the differences and changes over time. The GH folks write:
You can see the revision slider in action here but basically it takes each version and then overlays over the next using some nice transitions. Not unlike code diffs – the processes of comparing two iterations of a piece of software – this gives you far more control over the design process and lets you see where someone screwed up (or did something amazing).