Function dZoom

src/plots/cartesian/dragbox.js:1144–1147

(d)

// d<0 is expanding (cursor is off the plot, axis end moves
//  nonlinearly so you can expand far)
function dZoom(d) {
    return 1 - ((d >= 0) ? Math.min(d, 0.9) :
        1 / (1 / Math.max(d, -0.3) + 3.222));
}

function getDragCursor(nsew, dragmode, isMainDrag) {
    if(!nsew) return 'pointer';