Me las arreglé para destacar en mi gráfico dirigido por la fuerza, con la ayuda deeste tutorial de Mike Bostock. Ahora, para seguir con el procedimiento de mi idea y las necesidades de mi gráfica, estoy un poco atascado, en primer lugar porque todavía no sé nada sobre d3js y en segundo lugar, no encontré nada similar todavía.

Para borrar cuáles son mis intenciones, puede ver el gráfico actual resaltando en el siguiente enlace:http://jsfiddle.net/2FwSY/

Funciona bien, pero mi idea es un poco avanzada. Me preguntaba si es posible ajustar el resaltado de tal manera que al pasar el mouse al nodo, resaltaría los enlaces de ese nodo a los nodos vecinos, los nodos vecinos y también los enlaces de los nodos vecinos a los nodos vecinos.

Precisamente, en mi ejemplo jsfiddle. Si te quedasBNG , BNG, YHO, CEO y todolinks between them se pone de relieve. El problema es que los pequeños nodos azules que estoy usando como "conexión" entre nodos más grandes, mi punto culminante por ahora se "cortan" porque son nodos de hecho. También me parece que se necesitaría unIF declaración que diría si el nodo desplazado es ese pequeño o más grande, porque quiero que la iluminación en ese pequeño nodo de conexión esté funcionando como si ahora funcionara ...

No sé por dónde empezar, así que cualquier sugerencia o consejo es bienvenido ...

El script completo se ve así:

var data = {"nodes":[
                        {"name":"YHO", "full_name":"Yahoo", "type":1, "slug": "www.yahoo.com", "entity":"company", "img_hrefD":"", "img_hrefL":""},
                        {"name":"GGL", "full_name":"Google", "type":2, "slug": "www.google.com", "entity":"company", "img_hrefD":"", "img_hrefL":""},
                        {"name":"BNG", "full_name":"Bing", "type":2, "slug": "www.bing.com", "entity":"company", "img_hrefD":"", "img_hrefL":""},
                        {"name":"YDX", "full_name":"Yandex", "type":2, "slug": "www.yandex.com", "entity":"company", "img_hrefD":"", "img_hrefL":""},

                        {"name":"Desc1", "type":4, "slug": "", "entity":"description"},
                        {"name":"Desc2", "type":4, "slug": "", "entity":"description"},
                        {"name":"Desc4", "type":4, "slug": "", "entity":"description"},

                        {"name":"CEO", "prefix":"Mr.", "fst_name":"Jim", "snd_name":"Bean", "type":3, "slug": "", "entity":"employee"},
                        {"name":"ATT", "prefix":"Ms.", "fst_name":"Jenna", "snd_name":"Jameson", "type":3, "slug": "", "entity":"employee"},
                        {"name":"CTO", "prefix":"Mr.", "fst_name":"Lucky", "snd_name":"Luke", "type":3, "slug": "", "entity":"employee"},
                        {"name":"CDO", "prefix":"Ms.", "fst_name":"Pamela", "snd_name":"Anderson", "type":3, "slug": "", "entity":"employee"},
                        {"name":"CEO", "prefix":"Mr.", "fst_name":"Nacho", "snd_name":"Vidal", "type":3, "slug": "", "entity":"employee"},

                        {"name":"Desc5", "type":4, "slug": "", "entity":"description"},
                    ], 
            "links":[
                        {"source":0,"target":4,"value":1,"distance":5},
                        {"source":0,"target":5,"value":1,"distance":5},
                        {"source":0,"target":6,"value":1,"distance":5},

                        {"source":1,"target":4,"value":1,"distance":5},
                        {"source":2,"target":5,"value":1,"distance":5},
                        {"source":3,"target":6,"value":1,"distance":5},

                        {"source":7,"target":3,"value":10,"distance":6},
                        {"source":8,"target":3,"value":10,"distance":6},
                        {"source":9,"target":1,"value":10,"distance":6},
                        {"source":10,"target":1,"value":10,"distance":6},

                        {"source":11,"target":12,"value":10,"distance":6},
                        {"source":12,"target":2,"value":10,"distance":6},
                        ]
               }    



    var w = 560,
        h = 500,
        radius = d3.scale.log().domain([0, 312000]).range(["10", "50"]);

    var vis = d3.select("body").append("svg:svg")
        .attr("width", w)
        .attr("height", h);

        //vis.append("defs").append("marker")
        //.attr("id", "arrowhead")
        //.attr("refX", 22 + 3) /*must be smarter way to calculate shift*/
        //.attr("refY", 2)
        //.attr("markerWidth", 6)
        //.attr("markerHeight", 4)
        //.attr("orient", "auto")
        //.append("path")
            //.attr("d", "M 0,0 V 4 L6,2 Z"); //this is actual shape for arrowhead

    //d3.json(data, function(json) {
        var force = self.force = d3.layout.force()
            .nodes(data.nodes)
            .links(data.links)
            .linkDistance(function(d) { return (d.distance*10); })
            //.friction(0.5)
            .charge(-250)
            .size([w, h])
            .start();



        var link = vis.selectAll("line.link")
            .data(data.links)
            .enter().append("svg:line")
            .attr("class", function (d) { return "link" + d.value +""; })
            .attr("x1", function(d) { return d.source.x; })
            .attr("y1", function(d) { return d.source.y; })
            .attr("x2", function(d) { return d.target.x; })
            .attr("y2", function(d) { return d.target.y; })
            .attr("marker-end", function(d) {
                                                if (d.value == 1) {return "url(#arrowhead)"}
                                                else    { return " " }
                                            ;});




        function openLink() {
            return function(d) {
                var url = "";
                if(d.slug != "") {
                    url = d.slug
                } //else if(d.type == 2) {
                    //url = "clients/" + d.slug
                //} else if(d.type == 3) {
                    //url = "agencies/" + d.slug
                //}
                window.open("//"+url)
            }
        }




        var node = vis.selectAll("g.node")
            .data(data.nodes)
          .enter().append("svg:g")
            .attr("class", "node")
            .call(force.drag);


        node.append("circle")
            .attr("class", function(d){ return "node type"+d.type})
            .attr("r",function(d){if(d.entity == "description"){ return 6 } else { return 18 }})
            //.on("mouseover", expandNode);
            //.style("fill", function(d) { return fill(d.type); })



        node.append("text")
            .attr("class", function(d){ return "nodetext title_"+d.name })
            .attr("dx", 0)
            .attr("dy", ".35em")
            .style("font-size","10px")
            .attr("text-anchor", "middle")
            .style("fill", "white")
            .text(function(d) { if (d.entity != "description"){return d.name} });



        node.on("mouseover", function (d) {
            if (d.entity == "company"){   
                d3.select(this).select('text')
                    .transition()
                    .duration(300)
                    .text(function(d){
                            return d.full_name;
                        })
                    .style("font-size","15px")

            }
            else if(d.entity == "employee"){
                var asdf = d3.select(this);
                asdf.select('text').remove();

                asdf.append("text")
                            .text(function(d){return d.prefix + ' ' + d.fst_name })
                            .attr("class","nodetext")
                            .attr("dx", 0)
                            .attr("dy", ".35em")
                            .style("font-size","5px")
                            .attr("text-anchor", "middle")
                            .style("fill", "white")
                            .transition()
                            .duration(300)
                            .style("font-size","12px");

                asdf.append("text").text(function(d){return d.snd_name })
                            .attr("class","nodetext")
                            .attr("transform","translate(0, 12)")
                            .attr("dx", 0)
                            .attr("dy", ".35em")
                            .style("font-size","5px")
                            .attr("text-anchor", "middle")
                            .style("fill", "white")
                            .transition()
                            .duration(300)
                            .style("font-size","12px");                                         
            }
            else {
                d3.select(this).select('text')
                    .transition()
                    .duration(300)
                    .style("font-size","15px")
            }

            if (d.entity == "company") {
                d3.select(this).select('image')
                    .attr("width", "90px")
                    .attr("x", "-46px")
                    .attr("y", "-36.5px")
                    .attr("xlink:href", function (d) {
                        return d.img_hrefL
                        });               
            }

            if (d.entity == "company") {

                d3.select(this).select('circle')
                                .transition()
                                .duration(300)
                                .attr("r",28)

            }
            else if (d.entity == "employee"){
                d3.select(this).select('circle')
                                .transition()
                                .duration(300)
                                .attr("r",32)
            }
        })


         node.on("mouseout", function (d) {
            if (d.entity == "company") {
                d3.select(this).select('text')
                    .transition()
                    .duration(300)
                    .text(function(d){return d.name;})
                    .style("font-size","10px")
                }
            else if(d.entity == "employee"){
                ///////////////////////////
                // CHANGE
                ///////////////////////////

                d3.select(this).selectAll('text').remove();

                //d3.select(this).select('text')
                d3.select(this).append('text')
                    .text(function(d){return d.name;})
                    .style("font-size","14px")  
                    .attr("dx", 0)
                    .attr("dy", ".35em")
                    .attr("text-anchor", "middle")
                    .style("fill", "white")
                    .attr("class","nodetext")
                    .transition()
                    .duration(300)
                    .style("font-size","10px")

            }
            else {
                d3.select(this).select('text')
                    .transition()
                    .duration(300)
                    .style("font-size","10px")
            }


             if (d.entity == "company") {
                d3.select(this).select('image')
                    .attr("width", "70px")
                    .attr("x", "-36px")
                    .attr("y", "-36px")
                    .attr("xlink:href", function (d) {
                    return d.img_hrefD
                });
            }

            if (d.entity == "company" || d.entity == "employee") {

                d3.select(this).select('circle')
                                .transition()
                                .duration(300)
                                .attr("r",18)
            }

        });

        node.on("mouseover", fade(.4,"red"))
            .on("mouseout", fade(1));

var linkedByIndex = {};
    data.links.forEach(function(d) {
        linkedByIndex[d.source.index + "," + d.target.index] = 1;
    });

    function isConnected(a, b) {
        return linkedByIndex[a.index + "," + b.index] || linkedByIndex[b.index + "," + a.index] || a.index == b.index;
    }

        force.on("tick", function() {
          link.attr("x1", function(d) { return d.source.x; })
              .attr("y1", function(d) { return d.source.y; })
              .attr("x2", function(d) { return d.target.x; })
              .attr("y2", function(d) { return d.target.y; });

          node.attr("transform", function(d) { return "translate(" + d.x + "," + d.y + ")"; });
        });

        function fade(opacity,color) {
            return function(d) {

         node.style("stroke-opacity", function(o) {
            thisOpacity = isConnected(d, o) ? 1 : opacity;
            this.setAttribute('fill-opacity', thisOpacity);
            return thisOpacity;
        });

                link.style("stroke-opacity", function(o) {
                    return o.source === d || o.target === d ? 1 : opacity;
                })

                .style("stroke", function(o) {
                    return o.source === d || o.target === d ? color : "#000" ;
                });
            };

            }
    //});