Function zoomPrep

src/plots/ternary/ternary.js:578–621

(e, startX, startY)

    }

    function zoomPrep(e, startX, startY) {
        var dragBBox = dragger.getBoundingClientRect();
        x0 = startX - dragBBox.left;
        y0 = startY - dragBBox.top;

        gd._fullLayout._calcInverseTransform(gd);
        var inverse = gd._fullLayout._invTransform;
        var transformedCoords = Lib.apply3DTransform(inverse)(x0, y0);
        x0 = transformedCoords[0];
        y0 = transformedCoords[1];

        mins0 = {
            a: _this.aaxis.range[0],
            b: _this.baxis.range[1],
            c: _this.caxis.range[1]
        };
        mins = mins0;
        span0 = _this.aaxis.range[1] - mins0.a;
        lum = tinycolor(_this.graphDiv._fullLayout[_this.id].bgcolor).getLuminance();
        path0 = 'M0,' + _this.h + 'L' + (_this.w / 2) + ', 0L' + _this.w + ',' + _this.h + 'Z';
        dimmed = false;

        zb = zoomLayer.append('path')
            .attr('class', 'zoombox')
            .attr('transform', strTranslate(_this.x0, _this.y0))
            .style({
                fill: lum > 0.2 ? 'rgba(0,0,0,0)' : 'rgba(255,255,255,0)',
                'stroke-width': 0
            })
            .attr('d', path0);

        corners = zoomLayer.append('path')
            .attr('class', 'zoombox-corners')
            .attr('transform', strTranslate(_this.x0, _this.y0))
            .style({
                fill: Color.background,
                stroke: Color.defaultLine,
                'stroke-width': 1,
                opacity: 0
            })
            .attr('d', 'M0,0Z');

        _this.clearOutline(gd);
    }

    function getAFrac(x, y) { return 1 - (y / _this.h); }
    function getBFrac(x, y) { return 1 - ((x + (_this.h - y) / Math.sqrt(3)) / _this.w); }