Sketchup like snap angle <- Is it new ?

[Anonymous]

This function might have been existing for a long time, but I have just discovered this trick :

When you draw a polygonal element, with differently oriented edges, you can force your cursor to stay on the extension line of another edge by hovering the mouse on that edge and press the shift key.

Unfortunately, it won't work with external elements...

[Link]

Yes and if you use these constraints, it can be quite a powerful tool...

Cheers,
Link.