When trying to paint accurately along a contour to build a mask or get rid of unwanted image details, I find it difficult to stay exactly on my intended area. With a mouse, it´s even worse, to be honest, painting is a hassle to me, i just don´t get it right. It would be really helpful to have a function like painting with a shift, control or alt-key pressed would make the paintbrush draw a straight line to the next point being clicked on. So one could follow a contour with the paintbrush, clicking on and on and the strokes would just draw connected, not as a line of dots.
