miklobit/index.html

## readme.md

      
    Raw
  

              readme.md
            
          
    Demonstrates how to use the getTotalLength and getPointAtLength methods on SVG path elements to interpolate a point along an existing path. Built with D3.

  
## index.html
<!DOCTYPE html>
<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html;charset=utf-8"/>
    <title>Point-Along-Path Interpolation</title>
    <script type="text/javascript" src="http://mbostock.github.com/d3/d3.js?2.4.6"></script>
    <style type="text/css">

path {
  cursor: pointer;
  fill: #eee;
  stroke: #666;
  stroke-width: 1.5px;
}

circle {
  fill: steelblue;
  stroke: white;
  stroke-width: 1.5px;
}

    </style>
  </head>
  <body>
    <script type="text/javascript">

var w = 960,
    h = 500;

var svg = d3.select("body").append("svg:svg")
    .attr("width", w)
    .attr("height", h)
  .append("svg:g")
    .attr("transform", "translate(" + w / 2 + "," + h / 2 + ")");

var path = svg.append("svg:path")
    .attr("d", d3.svg.arc()
    .innerRadius(h / 4)
    .outerRadius(h / 3)
    .startAngle(0)
    .endAngle(Math.PI));

var circle = svg.append("svg:circle")
    .attr("r", 6.5)
    .attr("transform", "translate(0," + -h / 3 + ")");

function transition() {
  circle.transition()
      .duration(5000)
      .attrTween("transform", translateAlong(path.node()))
      .each("end", transition);
}

transition();

// Returns an attrTween for translating along the specified path element.
function translateAlong(path) {
  var l = path.getTotalLength();
  return function(d, i, a) {
    return function(t) {
      var p = path.getPointAtLength(t * l);
      return "translate(" + p.x + "," + p.y + ")";
    };
  };
}

    </script>
  </body>
</html>

## thumbnail.png

      
    Raw
  

              thumbnail.png
	<!DOCTYPE html>
	<html>
	<head>
	<meta http-equiv="Content-Type" content="text/html;charset=utf-8"/>
	<title>Point-Along-Path Interpolation</title>
	<script type="text/javascript" src="http://mbostock.github.com/d3/d3.js?2.4.6"></script>
	<style type="text/css">

	path {
	cursor: pointer;
	fill: #eee;
	stroke: #666;
	stroke-width: 1.5px;
	}

	circle {
	fill: steelblue;
	stroke: white;
	stroke-width: 1.5px;
	}

	</style>
	</head>
	<body>
	<script type="text/javascript">

	var w = 960,
	h = 500;

	var svg = d3.select("body").append("svg:svg")
	.attr("width", w)
	.attr("height", h)
	.append("svg:g")
	.attr("transform", "translate(" + w / 2 + "," + h / 2 + ")");

	var path = svg.append("svg:path")
	.attr("d", d3.svg.arc()
	.innerRadius(h / 4)
	.outerRadius(h / 3)
	.startAngle(0)
	.endAngle(Math.PI));

	var circle = svg.append("svg:circle")
	.attr("r", 6.5)
	.attr("transform", "translate(0," + -h / 3 + ")");

	function transition() {
	circle.transition()
	.duration(5000)
	.attrTween("transform", translateAlong(path.node()))
	.each("end", transition);
	}

	transition();

	// Returns an attrTween for translating along the specified path element.
	function translateAlong(path) {
	var l = path.getTotalLength();
	return function(d, i, a) {
	return function(t) {
	var p = path.getPointAtLength(t * l);
	return "translate(" + p.x + "," + p.y + ")";
	};
	};
	}

	</script>
	</body>
	</html>