fill 2D polygon between brush strokes when moving the brush while painting

[cmhulbert]

Currently, click-and-drag painting incurs a large amount of over-painting, since the entire area of the brush is painted, even if for example, you only moved by one pixel, and thus the vast majority of the brush volume was painted in the previous paint call.

An alternative would be to determine the location of the previous and current brush movement, and fill a rectangle between them with 2D javafx graphics primitives. You would still over-paint some, on the ends, but significantly less than the current paint operation.