Arco elíptico flecha borde d3 diseño forzado

Question

Oct 05, 2017, 09:15 PM

Arco elíptico flecha borde d3 diseño forzado

Estoy usando un diseño forzado para crear un gráfico dirigido. Su renderizado sobre lienzo. Mi ejemplo de muestra está enhttp://jsbin.com/vuyapibaqa/1/edit?html,output

Ahora estoy inspirado de
https://bl.ocks.org/mattkohl/146d301c0fc20d89d85880df537de7b0#index.html

Pocos recursos en d3 svg, algo similar que estoy tratando de obtener en el lienzo.

http://jsfiddle.net/zhanghuancs/a2QpA/

http://bl.ocks.org/mbostock/1153292 https://bl.ocks.org/ramtob/3658a11845a89c4742d62d32afce3160
http://bl.ocks.org/thomasdobber/9b78824119136778052f64a967c070e0 Dibujando múltiples aristas entre dos nodos con d3.

Quiere agregar arcos elípticos que conectan el borde con la flecha. Cómo lograr esto en lienzo.

Mi código :

<!DOCTYPE html>
<html>
<head>
        <title>Sample Graph Rendring Using Canvas</title>
        <script src="https://rawgit.com/gka/randomgraph.js/master/randomgraph.js"></script>
        <script src="https://d3js.org/d3.v4.min.js"></script>
</head>
<body>
    <script>
        var graph = {}//randomgraph.WattsStrogatz.beta(15, 4, 0.06);

    graph.nodes = [{"label":"x"} , {"label":"y"}];
    graph.edges = [{source:0,target:1},{source:0,target:1},
                   {source:1,target:0}]

        var canvas = null
        var width = window.innerWidth,
            height = window.innerHeight;
        canvas = d3.select("body").append("canvas").attr("width",width).attr("height",height);

        var context = canvas.node().getContext("2d");


        force = d3.forceSimulation()
                .force("link", d3.forceLink().id(function(d) { 
                     return d.index;
                })).force("charge", d3.forceManyBody())
                .force("center", d3.forceCenter(width / 2, height / 2));

        force.nodes(graph.nodes);
        force.force("link").links(graph.edges).distance(200);

        var detachedContainer = document.createElement("custom");
            dataContainer = d3.select(detachedContainer);

        link = dataContainer.selectAll(".link").data(graph.edges)
              .enter().append("line").attr("class", "link")
              .style("stroke-width", 2)

        node = dataContainer.selectAll(".node").data(graph.nodes)
              .enter().append("g");

          var circles = node.append("circle")
              .classed("circle-class", true)
              .attr("class", function (d){ return "node node_" + d.index;})
              .attr("r", 5)
              .attr("fill", 'red')
              .attr("strokeStyle", 'black');

        d3.timer(function(){
            context.clearRect(0, 0, width, height);

            // draw links
            link.each(function(d) {
              context.strokeStyle = "#ccc";
              /***** Elliptical arcs *****/
              context.stroke(new Path2D(linkArc(d)));
              /***** Elliptical arcs *****/
            });

            context.lineWidth = 2;
            node.each(function(d) {

              context.beginPath();
              context.moveTo(d.x, d.y);
              var r = d3.select(this).select("circle").node().getAttribute('r');   

              d.x = Math.max(30, Math.min(width - 30, d.x));
              d.y = Math.max(30, Math.min(height - 30, d.y));         
              context.closePath();
              context.arc(d.x, d.y, r, 0, 2 * Math.PI);

              context.fillStyle = d3.select(this).select("circle").node().getAttribute('fill');
              context.strokeStyle = d3.select(this).select("circle").node().getAttribute('strokeStyle');
              context.stroke();
              context.fill();

              context.beginPath();
              context.arc(d.x + 15, d.y-20, 5, 0, 2 * Math.PI);
              context.fillStyle = "orange";
              context.strokeStyle = "orange";
              var data = d3.select(this).data();
              context.stroke();
              context.fill();
              context.font = "10px Arial";
              context.fillStyle = "black";
              context.strokeStyle = "black";
              context.fillText(parseInt(data[0].index),d.x + 10, d.y-15);
            });

        });

        circles.transition().duration(5000).attr('r', 20).attr('fill', 'orange');

        canvas.node().addEventListener('click',function( event ){
           console.log(event)
            // Its COMING ANY TIME INSIDE ON CLICK OF CANVAS
        });

        /***** Elliptical arcs *****/
        function linkArc(d) {
          var dx = d.target.x - d.source.x,
              dy = d.target.y - d.source.y,
              dr = Math.sqrt(dx * dx + dy * dy);
          return "M" + d.source.x + "," + d.source.y + "A" + dr + "," + dr + " 0 0,1 " + d.target.x + "," + d.target.y;
        }
        /***** Elliptical arcs *****/
    </script>
</body>
</html>