| license: mit |
Adapted from Mike Bostock's Zoomable Sunburst to include arc labels.
Click on any arc to zoom in. Click on the center circle to zoom out. Click on canvas background to reset zoom.
forked from vasturiano's block: Zoomable Sunburst with Labels
forked from lorenzopub's block: Zoomable Sunburst with Labels
| <head> | |
| <style> | |
| body { | |
| font-family: Sans-serif; | |
| font-size: 11px; | |
| } | |
| .slice { | |
| cursor: pointer; | |
| } | |
| .slice .main-arc { | |
| stroke: #fff; | |
| stroke-width: 1px; | |
| } | |
| .slice .hidden-arc { | |
| fill: none; | |
| } | |
| .slice text { | |
| pointer-events: none; | |
| dominant-baseline: middle; | |
| text-anchor: middle; | |
| } | |
| </style> | |
| <script src='https://d3js.org/d3.v4.min.js'></script> | |
| </head> | |
| <body> | |
| <script> | |
| const width = window.innerWidth, | |
| height = window.innerHeight, | |
| maxRadius = (Math.min(width, height) / 2) - 5; | |
| const formatNumber = d3.format(',d'); | |
| const x = d3.scaleLinear() | |
| .range([0, 2 * Math.PI]) | |
| .clamp(true); | |
| const y = d3.scaleSqrt() | |
| .range([maxRadius*.1, maxRadius]); | |
| const color = d3.scaleOrdinal(d3.schemeCategory20); | |
| const partition = d3.partition(); | |
| const arc = d3.arc() | |
| .startAngle(d => x(d.x0)) | |
| .endAngle(d => x(d.x1)) | |
| .innerRadius(d => Math.max(0, y(d.y0))) | |
| .outerRadius(d => Math.max(0, y(d.y1))); | |
| const middleArcLine = d => { | |
| const halfPi = Math.PI/2; | |
| const angles = [x(d.x0) - halfPi, x(d.x1) - halfPi]; | |
| const r = Math.max(0, (y(d.y0) + y(d.y1)) / 2); | |
| const middleAngle = (angles[1] + angles[0]) / 2; | |
| const invertDirection = middleAngle > 0 && middleAngle < Math.PI; // On lower quadrants write text ccw | |
| if (invertDirection) { angles.reverse(); } | |
| const path = d3.path(); | |
| path.arc(0, 0, r, angles[0], angles[1], invertDirection); | |
| return path.toString(); | |
| }; | |
| const textFits = d => { | |
| const CHAR_SPACE = 6; | |
| const deltaAngle = x(d.x1) - x(d.x0); | |
| const r = Math.max(0, (y(d.y0) + y(d.y1)) / 2); | |
| const perimeter = r * deltaAngle; | |
| console.log(d.data) | |
| if(d.data.name) return d.data.name.length * CHAR_SPACE < perimeter; | |
| }; | |
| const svg = d3.select('body').append('svg') | |
| .style('width', '100vw') | |
| .style('height', '100vh') | |
| .attr('viewBox', `${-width / 2} ${-height / 2} ${width} ${height}`) | |
| .on('click', () => focusOn()); // Reset zoom on canvas click | |
| d3.json('https://graphics.thomsonreuters.com/data/europe-election/sunburst.json', (error, root) => { | |
| if (error) throw error; | |
| root = d3.hierarchy(root); | |
| root.sum(d => d.seatsTotal); | |
| const slice = svg.selectAll('g.slice') | |
| .data(partition(root).descendants()); | |
| slice.exit().remove(); | |
| const newSlice = slice.enter() | |
| .append('g').attr('class', 'slice') | |
| .on('click', d => { | |
| d3.event.stopPropagation(); | |
| focusOn(d); | |
| }); | |
| newSlice.append('title') | |
| .text(d => d.data.name + '\n' + formatNumber(d.value)); | |
| newSlice.append('path') | |
| .attr('class', 'main-arc') | |
| .style('fill', d => color((d.children ? d : d.parent).data.name)) | |
| .attr('d', arc); | |
| newSlice.append('path') | |
| .attr('class', 'hidden-arc') | |
| .attr('id', (_, i) => `hiddenArc${i}`) | |
| .attr('d', middleArcLine); | |
| const text = newSlice.append('text') | |
| .attr('display', d => textFits(d) ? null : 'none'); | |
| // Add white contour | |
| text.append('textPath') | |
| .attr('startOffset','50%') | |
| .attr('xlink:href', (_, i) => `#hiddenArc${i}` ) | |
| .text(d => d.data.name) | |
| .style('fill', 'none') | |
| .style('stroke', '#fff') | |
| .style('stroke-width', 5) | |
| .style('stroke-linejoin', 'round'); | |
| text.append('textPath') | |
| .attr('startOffset','50%') | |
| .attr('xlink:href', (_, i) => `#hiddenArc${i}` ) | |
| .text(d => d.data.name); | |
| }); | |
| function focusOn(d = { x0: 0, x1: 1, y0: 0, y1: 1 }) { | |
| // Reset to top-level if no data point specified | |
| const transition = svg.transition() | |
| .duration(750) | |
| .tween('scale', () => { | |
| const xd = d3.interpolate(x.domain(), [d.x0, d.x1]), | |
| yd = d3.interpolate(y.domain(), [d.y0, 1]); | |
| return t => { x.domain(xd(t)); y.domain(yd(t)); }; | |
| }); | |
| transition.selectAll('path.main-arc') | |
| .attrTween('d', d => () => arc(d)); | |
| transition.selectAll('path.hidden-arc') | |
| .attrTween('d', d => () => middleArcLine(d)); | |
| transition.selectAll('text') | |
| .attrTween('display', d => () => textFits(d) ? null : 'none'); | |
| moveStackToFront(d); | |
| // | |
| function moveStackToFront(elD) { | |
| svg.selectAll('.slice').filter(d => d === elD) | |
| .each(function(d) { | |
| this.parentNode.appendChild(this); | |
| if (d.parent) { moveStackToFront(d.parent); } | |
| }) | |
| } | |
| } | |
| </script> | |
| </body> |