Thanks for trying it! Yes, it is pretty much unusable with a mouse, but it was kind of fun on an iPad or with a Wacom Tablet. I remember that I had some problems with the touch events on the iPad - I eventually solved them (http://davidtanzer.net/canvas_ipad), but I'm not sure if I deployed the fixed version...
As I said, the project is pretty much dead now. But your idea (listening for mouse up on the document) would probably solve several problems, thanks!
As I said, the project is pretty much dead now. But your idea (listening for mouse up on the document) would probably solve several problems, thanks!