D3 Examples - Pan & Zoom with click

Pan & Zoom with click

This example demonstrates using d3-zoom to pan and zoom an SVG element by applying an SVG transform using transform.toString. The zoom behavior is applied to an invisible rect overlaying the SVG element; this ensures that it receives input, and that the pointer coordinates are not affected by the zoom behavior’s transform.

xxxxxxxxxx
 
<!DOCTYPE html>
<meta charset="utf-8">
<div>
  Client : X : <span id="lastX"></span> | Y : <span id="lastY"></span><br />
  SVG : X : <span id="lastXsvg"></span> | Y : <span id="lastYsvg"></span><br />
</div>
<svg width="960" height="500" id="svg"></svg>
<script src="https://d3js.org/d3.v4.min.js"></script>
<script>
​
​
function transformCoordinates(coordinatesInArray) {
        var mySvg = document.getElementById("svg");
        var myPoint = mySvg.createSVGPoint();
        myPoint.x = coordinatesInArray[0];
        myPoint.y = coordinatesInArray[1];
        var myNewPoint = myPoint.matrixTransform( mySvg.getScreenCTM().inverse() );
​
        return [ myNewPoint.x, myNewPoint.y ];
    }
      
var svg = d3.select("svg"),
    width = +svg.attr("width"),
    height = +svg.attr("height");
​
var points = d3.range(1).map(phyllotaxis(10));
​
var g = svg.append("g");
​
  svg.on("click", () => {
    var myEvent = d3.event;
​
    document.getElementById("lastX").innerHTML = myEvent.clientX;
    document.getElementById("lastY").innerHTML = myEvent.clientY;
    
    var myComputeCoordinates = transformCoordinates([myEvent.clientX, myEvent.clientY])
    document.getElementById("lastXsvg").innerHTML = myComputeCoordinates[0];
    document.getElementById("lastYsvg").innerHTML = myComputeCoordinates[1];
  })
g.selectAll("circle")
    .data(points)
  .enter().append("circle")
    .attr("cx", function(d) { return d[0]; })
    .attr("cy", function(d) { return d[1]; })
    .attr("r", 10);
​
var myRect = svg.append("rect")
    .attr("width", width)
    .attr("height", height)
    .style("fill", "none")
    .style("pointer-events", "all")
    .call(d3.zoom()
        .scaleExtent([1 / 2, 4])
        .on("zoom", zoomed));
  
  
function zoomed() {
  g.attr("transform", d3.event.transform);
}
​
function phyllotaxis(radius) {
  var theta = Math.PI * (3 - Math.sqrt(5));
  return function(i) {
    var r = radius * Math.sqrt(i), a = theta * i;
    return [
      width / 2 + r * Math.cos(a),
      height / 2 + r * Math.sin(a)
    ];
  };
}
​
</script>
​
    