Function getScrollBarDragY

src/components/legend/draw.js:386–389

(scrollBoxY0, eventY0, eventY1)

                var eventY0, eventY1, scrollBoxY0;

                var getScrollBarDragY = function(scrollBoxY0, eventY0, eventY1) {
                    var y = ((eventY1 - eventY0) / scrollRatio) + scrollBoxY0;
                    return Lib.constrain(y, 0, scrollBoxYMax);
                };

                var getNaturalDragY = function(scrollBoxY0, eventY0, eventY1) {
                    var y = ((eventY0 - eventY1) / scrollRatio) + scrollBoxY0;