Ages ago, in my own editor (and missing HP chipmunk physical "paddle wheel" scrolling), I implemented the following mouse scrolling scheme: - Integrate the area* enclosed by recent mouse movement - Ignore everything under a threshold (this is normal, straight-line, mousing) - Scroll according to the sign of the area. . naively this would be slow scroll for small circles; fast for large . but I found it more intuitive…
IIRC the gesture starts at the edge of the trackpad much like regular edge scrolling, but then you can extend the motion to the entire working area of the trackpad, pretending to spin an imaginary jog wheel.