Tristaric

That's... not entirely what I meant, @Pixey. I'm asking for shapes that you can morph/transform/deform in the canvas itself, like the line tool, not making predefined shapes.

It would be nice if there were a plugin of some sort that allowed shapes (elipse, rectangle, etc), but had the same level of transformation similar to the line tool. Where you have multiple points along the shape that you can click and drag, and the shape will respond to it, instead of just having transform tools similar to a rectangular selection.