Wondering what would be involved in adding new commands to the Sketcher mod? I'm looking to add several "helper" objects to it, similar to sketching tools in autodesk inventor. My first goal would be a new rectangle object that behaves similar to the ellipse by center command, but instead using 2 clicks (center, one corner). With the construction lines included. Next would be an aligned rectangle where you start with a line to define the orientation (angle) of the rectangle. Then there are several different methods of defining slots, etc.
Is it possible to do all this using only python? Where would I start?