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How to center a List inside a D3 circle

I have a List of items that are inside a circle. I am using hardcoded values for the alignment. I need it to be based off the central point of the circle and by the length of the array.
Need to get rid of these "yAxis: -40, yAxis: -40, yAxis: 0, yAxis: 20";
And also have some space between line items.
const w = 500,
h = 400,
r = 160;
const STREAMS = [{
label: 'Emissions',
isSelected: true,
yAxis: -40
}, {
label: 'Energy Produced',
isSelected: false,
yAxis: -20
}, {
label: 'Energy Consumed',
isSelected: false,
yAxis: 0
}, {
label: 'Intensity',
isSelected: false,
yAxis: 20
}]
const SUB_STREAMS = [{
value: 0.15,
label: 'Total',
isSelected: true
}, {
value: 0.2,
label: 'CO2',
isSelected: false
}, {
value: 0.25,
label: 'Methane',
isSelected: false
}, {
value: 0.30,
label: 'N2O',
isSelected: false
}, {
value: 0.35,
label: 'Other',
isSelected: false
}];
const svg = d3.select("#foo")
.append("svg")
.attr("width", w)
.attr("height", h);
const g = svg.append("g")
.attr("transform", "translate(" + [w / 2, h / 2] + ")");
g.append("circle")
.attr("r", r)
.style("fill", "none")
.style("stroke", "black");
const points = g.selectAll(null)
.data(SUB_STREAMS)
.enter()
.append("circle")
.attr('stroke', 'dodgerblue')
.attr('stroke-width', 1)
.style("fill", function(d) {
return d.isSelected ? 'dodgerblue' : 'white'
})
.attr("r", 12)
.attr("cx", function(d) {
return r * Math.cos(d.value * Math.PI * 2 - Math.PI / 2)
})
.attr("cy", function(d) {
return r * Math.sin(d.value * Math.PI * 2 - Math.PI / 2)
})
points.on("click", function(d) {
console.log(d)
})
g.selectAll(null)
.data(SUB_STREAMS)
.enter()
.append('text')
.style('cursor', 'pointer')
.style('fill', 'black')
.attr('text-anchor', 'right')
.attr('font-size', '1.3em')
.attr('dx', (d) => 14 + r * Math.cos(d.value * Math.PI * 2 - Math.PI / 2))
.attr('dy', (d) => r * Math.sin(d.value * Math.PI * 2 - Math.PI / 2))
.text((d) => d.label)
const text = g
.selectAll('path')
.data(STREAMS)
.enter()
.append("text")
.attr("text-anchor", "left")
.attr('font-size', '1em')
.attr("y", function(d, a) {
return d.yAxis - 5
})
.text((d) => d.label);
text.on("click", function(d) {
console.log(d)
})
var arc = d3.symbol().type(d3.symbolTriangle)
var line = g.selectAll('path')
.data(STREAMS)
.enter()
.append('path')
.attr('d', arc)
.attr('fill', 'red')
.attr('stroke', '#000')
.attr('stroke-width', 1)
.attr('transform', function(d) {
return `translate(-10,${d.yAxis - 5}) rotate(210)`;
});
text {
dominant-baseline: central;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/5.7.0/d3.min.js"></script>
<div id="foo" />

One solution out of many is setting a padding...
const padding = 20
...and translating the container groups by their indices times that padding:
const groups = g
.selectAll('path')
.data(STREAMS)
.enter()
.append("g")
.attr("transform", (_, i) => "translate(0," +
(-padding * (STREAMS.length - 1) / 2 + i * padding) + ")");
Then, you append both texts and paths to those groups.
Here is your code with those changes:
const w = 500,
h = 400,
r = 160,
padding = 20;
const STREAMS = [{
label: 'Emissions',
isSelected: true
}, {
label: 'Energy Produced',
isSelected: false
}, {
label: 'Energy Consumed',
isSelected: false
}, {
label: 'Intensity',
isSelected: false
}]
const SUB_STREAMS = [{
value: 0.15,
label: 'Total',
isSelected: true
}, {
value: 0.2,
label: 'CO2',
isSelected: false
}, {
value: 0.25,
label: 'Methane',
isSelected: false
}, {
value: 0.30,
label: 'N2O',
isSelected: false
}, {
value: 0.35,
label: 'Other',
isSelected: false
}];
const svg = d3.select("#foo")
.append("svg")
.attr("width", w)
.attr("height", h);
const g = svg.append("g")
.attr("transform", "translate(" + [w / 2, h / 2] + ")");
g.append("circle")
.attr("r", r)
.style("fill", "none")
.style("stroke", "black");
const points = g.selectAll(null)
.data(SUB_STREAMS)
.enter()
.append("circle")
.attr('stroke', 'dodgerblue')
.attr('stroke-width', 1)
.style("fill", function(d) {
return d.isSelected ? 'dodgerblue' : 'white'
})
.attr("r", 12)
.attr("cx", function(d) {
return r * Math.cos(d.value * Math.PI * 2 - Math.PI / 2)
})
.attr("cy", function(d) {
return r * Math.sin(d.value * Math.PI * 2 - Math.PI / 2)
})
points.on("click", function(d) {
console.log(d)
})
g.selectAll(null)
.data(SUB_STREAMS)
.enter()
.append('text')
.style('cursor', 'pointer')
.style('fill', 'black')
.attr('text-anchor', 'right')
.attr('font-size', '1.3em')
.attr('dx', (d) => 14 + r * Math.cos(d.value * Math.PI * 2 - Math.PI / 2))
.attr('dy', (d) => r * Math.sin(d.value * Math.PI * 2 - Math.PI / 2))
.text((d) => d.label)
const groups = g
.selectAll('path')
.data(STREAMS)
.enter()
.append("g")
.attr("transform", (_, i) => "translate(0," + (-padding * (STREAMS.length - 1) / 2 + i * padding) + ")");
groups.append("text")
.attr('font-size', '1em')
.text((d) => d.label)
.on("click", function(d) {
console.log(d)
})
var arc = d3.symbol().type(d3.symbolTriangle)
groups.append('path')
.attr('d', arc)
.attr('fill', 'red')
.attr('stroke', '#000')
.attr('stroke-width', 1)
.attr('transform', function(d) {
return "translate(-10,0) rotate(210)";
});
text {
dominant-baseline: central;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/5.7.0/d3.min.js"></script>
<div id="foo" />
And here the same code, with a bigger data array, so you can see that it dynamically sets the positions according to the number of elements:
const w = 500,
h = 400,
r = 160,
padding = 20;
const STREAMS = [{
label: 'Emissions',
isSelected: true
}, {
label: 'Energy Produced',
isSelected: false
}, {
label: 'Energy Consumed',
isSelected: false
}, {
label: 'Intensity',
isSelected: false
}, {
label: 'Foo',
isSelected: false
}, {
label: 'Bar',
isSelected: false
}, {
label: 'Baz',
isSelected: false
}]
const SUB_STREAMS = [{
value: 0.15,
label: 'Total',
isSelected: true
}, {
value: 0.2,
label: 'CO2',
isSelected: false
}, {
value: 0.25,
label: 'Methane',
isSelected: false
}, {
value: 0.30,
label: 'N2O',
isSelected: false
}, {
value: 0.35,
label: 'Other',
isSelected: false
}];
const svg = d3.select("#foo")
.append("svg")
.attr("width", w)
.attr("height", h);
const g = svg.append("g")
.attr("transform", "translate(" + [w / 2, h / 2] + ")");
g.append("circle")
.attr("r", r)
.style("fill", "none")
.style("stroke", "black");
const points = g.selectAll(null)
.data(SUB_STREAMS)
.enter()
.append("circle")
.attr('stroke', 'dodgerblue')
.attr('stroke-width', 1)
.style("fill", function(d) {
return d.isSelected ? 'dodgerblue' : 'white'
})
.attr("r", 12)
.attr("cx", function(d) {
return r * Math.cos(d.value * Math.PI * 2 - Math.PI / 2)
})
.attr("cy", function(d) {
return r * Math.sin(d.value * Math.PI * 2 - Math.PI / 2)
})
points.on("click", function(d) {
console.log(d)
})
g.selectAll(null)
.data(SUB_STREAMS)
.enter()
.append('text')
.style('cursor', 'pointer')
.style('fill', 'black')
.attr('text-anchor', 'right')
.attr('font-size', '1.3em')
.attr('dx', (d) => 14 + r * Math.cos(d.value * Math.PI * 2 - Math.PI / 2))
.attr('dy', (d) => r * Math.sin(d.value * Math.PI * 2 - Math.PI / 2))
.text((d) => d.label)
const groups = g
.selectAll('path')
.data(STREAMS)
.enter()
.append("g")
.attr("transform", (_, i) => "translate(0," + (-padding * (STREAMS.length - 1) / 2 + i * padding) + ")");
groups.append("text")
.attr('font-size', '1em')
.text((d) => d.label)
.on("click", function(d) {
console.log(d)
})
var arc = d3.symbol().type(d3.symbolTriangle)
groups.append('path')
.attr('d', arc)
.attr('fill', 'red')
.attr('stroke', '#000')
.attr('stroke-width', 1)
.attr('transform', function(d) {
return "translate(-10,0) rotate(210)";
});
text {
dominant-baseline: central;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/5.7.0/d3.min.js"></script>
<div id="foo" />

Wrong nodes connection in a directed graph with d3.js

I am developing a directed graph with nodes in static position using d3.js library.
Currently I am having 3 nodes, and I want to connect the two computers with the printer. The edges are set to different positions as seen in this image:
How can i make the lines connect the nodes based on the nodes position?
Here is the code I have so far.
var width = 640,
height = 400;
var nodes = [
{ x: 184.53020651496104, y: 0, id: 0, url:
"http://icons.iconarchive.com/icons/tpdkdesign.net/refresh-
cl/32/Hardware-My-Computer-3-icon.png"},
{ x: 100, y: 150, id: 1, url:
"http://icons.iconarchive.com/icons/tpdkdesign.net/refresh-
cl/32/Hardware-My-Computer-3-icon.png" },
{ x: width/3, y: height/2, id: 2, url:
"http://icons.iconarchive.com/icons/tpdkdesign.net/refresh-
cl/32/Hardware-Printer-Blue-icon.png" },
];
var links = [
{ source: 1, target: 2 },
{ source: 0, target: 2 }
];
var graph = d3.select('#graph');
var svg = graph.append('svg')
.attr('width', width)
.attr('height', height);
var force = d3.layout.force()
.size([width, height])
.nodes(nodes)
.links(links);
force.linkDistance(width/2);
var link = svg.selectAll('.link')
.data(links)
.enter().append('line')
.attr('class', 'link');
var node = svg.selectAll('.node')
.data(nodes)
.enter().append("image")
.attr("xlink:href", d=> d.url)
.attr("x", d=> d.x)
.attr("y", d=> d.y)
.attr("width", 30)
.attr("height", 30)
.attr('class', 'node');
force.on('end', function() {
node.attr('r', width/25)
.attr('cx', function(d) { return d.x; })
.attr('cy', function(d) { return d.y; });
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; });
});
force.start();
Thank you in advance.

Position of node changes when they link (using d3.js)

I am a newbie in d3.js. I have tried to create a static architecture with 5 nodes and link them with each other according to preferences, the nodes should be organized like so:
At the beginning I set the position of the nodes and then create the links. Though, when the nodes get linked, the architecture changes and the result is the one displayed below:
Here is my code:
var width = 640,
height = 400;
var nodes = [
{ x: 60, y: 0, id: 0},
{ x: 150, y: height/4, id: 1},
{ x: 220, y: height/4, id: 2},
{ x: 340, y: height/4, id: 3},
{ x: 420, y: height/2, id: 4},
{ x: 480, y: height/2, id: 5}
];
var links = [
{ source: 1, target: 5 },
{ source: 0, target: 5 },
{ source: 2, target: 1 },
{ source: 3, target: 2 },
{ source: 4, target: 5 }
];
var graph = d3.select('#graph');
var svg = graph.append('svg')
.attr('width', width)
.attr('height', height);
var force = d3.layout.force()
.size([width, height])
.nodes(nodes)
.links(links);
force.linkDistance(width/2);
var link = svg.selectAll('.link')
.data(links)
.enter().append('line')
.attr('class', 'link');
var div = d3.select("body").append("div")
.attr("class", "tooltip")
.style("opacity", 1e-6);
var node = svg.selectAll('.node')
.data(nodes)
.enter().append("circle")
.attr("cx", d=> d.x)
.attr("cy", d=> d.y)
.attr('class', 'node')
.on("mouseover", function(d){
d3.select(this)
.transition()
.duration(500)
.style("cursor", "pointer")
div
.transition()
.duration(300)
.style("opacity", "1")
.style("display", "block")
console.log("label", d.label);
div
.html("IP: " + d.label + " x: " + d.x + " y: " + d.y)
.style("left", (d3.event.pageX ) + "px")
.style("top", (d3.event.pageY) + "px");
})
.on("mouseout", mouseout);
function mouseout() {
div.transition()
.duration(300)
.style("opacity", "0")
}
console.log("wait...");
force.on('end', function() {
node.attr('r', width/25)
.attr('cx', function(d) { return d.x; })
.attr('cy', function(d) { return d.y; });
link.attr('x1', function(d) { console.log("LINE x1-> ", d.source.x); return d.source.x; })
.attr('y1', function(d) { console.log("LINE y1-> ", d.source.y); return d.source.y; })
.attr('x2', function(d) { console.log("LINE x2-> ", d.source.x); return d.target.x; })
.attr('y2', function(d) { console.log("LINE y2-> ", d.source.y); return d.target.y; })
.attr("stroke-width", 2)
.attr("stroke","black");
});
force.start();
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.4.11/d3.min.js"></script>
<div id="graph"></div>
Could you please help me?
Thank you in advance.

A force layout offers some advantages that derive from its nature as a self organizing layout:
It places nodes and links automatically avoiding manual positioning of potentially thousands of elements
It organizes nodes and links based on assigned forces to an ideal spacing and layout
You have nodes to which you have already assigned positions, the two advantages listed above do not apply. You've already manually done the first item, and the second item will disturb and overwrite the positions you manually set.
We could fix the node positions, but if we do this with all nodes, it defeats the purpose of the force layout: to position nodes by simulating forces.
Instead, if you have the position of all nodes, we can skip the force and just append everything based on the data. The snippet below places the links first (so they are behind the nodes) using the index contained in d.source/d.target to access the specific node in the nodes array and get the appropriate x or y coordinate. The nodes are positioned normally.
It appears you have adjusted the code to use circles in your question though the screenshot uses images (as you also used in a previous question), I'll just use circles here. Based on the coordinates you've given some lines overlap. I modified the first node so that the y value wasn't 0 (which would have pushed half the circle off the svg)
var width = 640,
height = 400;
var nodes = [
{ x: 60, y: height/8, id: 0},
{ x: 150, y: height/4, id: 1},
{ x: 220, y: height/4, id: 2},
{ x: 340, y: height/4, id: 3},
{ x: 420, y: height/2, id: 4},
{ x: 480, y: height/2, id: 5}
];
var links = [
{ source: 1, target: 5 },
{ source: 0, target: 5 },
{ source: 2, target: 1 },
{ source: 3, target: 2 },
{ source: 4, target: 5 }
];
var graph = d3.select('#graph');
var svg = graph.append('svg')
.attr('width', width)
.attr('height', height);
// append links:
svg.selectAll()
.data(links)
.enter()
.append("line")
.attr("x1", function(d) { return nodes[d.source].x; })
.attr("y1", function(d) { return nodes[d.source].y; })
.attr("x2", function(d) { return nodes[d.target].x; })
.attr("y2", function(d) { return nodes[d.target].y; })
.attr("stroke-width", 2)
.attr("stroke","black");
// append nodes:
svg.selectAll()
.data(nodes)
.enter()
.append("circle")
.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; })
.attr("r", 8);
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.4.11/d3.min.js"></script>
<div id="graph"></div>

How can I wrap text on the each arc in D3.js?

Below is my code. I made a circle with 5 arcs and now I want to add text to each arc such that: http://bl.ocks.org/nbremer/raw/b603c3e0f7a74794da87/
// declarations
const svgSize = {
width: 1000,
height: 800
};
// setup
let svg = d3
.select('body')
.append('svg')
.attr('width', svgSize.width)
.attr('height', svgSize.height)
.append('g')
.attr('transform', 'translate(' + svgSize.width / 2 + ',' + svgSize.height / 2 + ')');
// drawing
let arcGenerator = d3.arc()
.innerRadius(296)
.outerRadius(300);
let arcData = [
{ startAngle: 0, endAngle: 0.2 },
{ startAngle: 0.2, endAngle: 0.6 },
{ startAngle: 0.6, endAngle: 1.4 },
{ startAngle: 1.4, endAngle: 3 },
{ startAngle: 3, endAngle: 2 * Math.PI }
];
d3.select('g')
.selectAll('path')
.data(arcData)
.enter()
.append('path')
.attr('d', arcGenerator);

d3.select('g')
.selectAll('path')
.data(arcData)
.enter()
.append('path')
.attr("id", (d, i) => { return "uniqueId_" + i; })
.attr('d', arcGenerator);
let monthData = [{ month: 'Jan' }, { month: 'Feb' }, { month: 'Mar' }, { month: 'Apr' }, { month: 'May' },]
// append the month names to each slice
svg.selectAll(".monthText")
.data(monthData)
.enter().append("text")
.attr("class", "monthText")
.attr("x", 10) // move the text from the start angle of the arc
.attr("dy", -10) // move the text down
.append("textPath")
.attr("xlink:href", function (d, i) { return "#uniqueId_" + i; })
.text(function (d) { return d.month; });

d3.js force layout drag stops working after deleting a node

I've seen this answer and this too, but they don't work.
My code is on Fiddle.
Two questions:
1. On clicking a node and pressing the delete button on the keyboard the node and corresponding links get deleted, but why am I not able to drag the remaining nodes afterward?
2. I tried attaching an image (using the path in the nodes array), but the image doesn't appear. The circles just disappear and no image appears (the path to the image is correct. In the same program I tried displaying the image at a corner of the screen and it worked).
The code:
<!DOCTYPE html>
<meta charset="utf-8">
<style>
.background { /*stroke: gray; stroke-width: 1px; fill: rgb(252,231,216);*/ cursor: move; }
.link { stroke: #000; stroke-width: 1.5px; }
.node { fill: #ccc; /*stroke: #000;*/ stroke-width: 1.5px; cursor: pointer;}
.node.fixed { fill: #f00; cursor: pointer;}
text { font: 10px sans-serif; pointer-events: none; text-shadow: 0 1px 0 #fff, 1px 0 0 #fff, 0 -1px 0 #fff, -1px 0 0 #fff; }
</style>
<body>
<script src="d3/d3.v3.js"></script>
<div id="topologyArea"></div>
<script>
var nodes = [//it's not necessary to give x and y values to nodes. One gets created for every empty object you insert here like this {}
{id: 1, x: 470, y: 410, icon: "images/abc.jpg"},
{id: 2, x: 493, y: 364, icon: "images/abc.jpg"},
{id: 3, x: 442, y: 365, icon: "images/abc.jpg"},
{id: 4, x: 467, y: 314, icon: "images/abc.jpg"},
{id: 5, x: 477, y: 248, icon: "images/fsd.jpg"},
{id: 6, x: 425, y: 207, icon: "images/sdfs.jpg"},
{id: 7, x: 402, y: 155, icon: "images/dfs.jpg"},
{id: 8, x: 369, y: 196, icon: "images/abc.jpg"},
{id: 9, x: 350, y: 148, icon: "images/abc.jpg"},
{id: 10, x: 539, y: 222, icon: "images/abc.jpg"},
{id: 11, x: 594, y: 235, icon: "images/abc.jpg"},
{id: 12, x: 582, y: 185, icon: "images/abc.jpg"},
{id: 13, x: 633, y: 200, icon: "images/abc.jpg"}
];
var links = [
{id: 1, source: 0, target: 1},
{id: 2, source: 1, target: 2},
{id: 3, source: 0, target: 2},
{id: 4, source: 1, target: 3},
{id: 5, source: 3, target: 2},
{id: 6, source: 3, target: 4},
{id: 7, source: 4, target: 5},
{id: 8, source: 5, target: 6},
{id: 9, source: 5, target: 7},
{id: 10, source: 6, target: 7},
{id: 11, source: 6, target: 8},
{id: 12, source: 7, target: 8},
{id: 13, source: 9, target: 4},
{id: 14, source: 9, target: 11},
{id: 15, source: 9, target: 10},
{id: 16, source: 10, target: 11},
{id: 17, source: 11, target: 12},
{id: 18, source: 12, target: 10}
];
var margin = {top: -5, right: -5, bottom: -5, left: -5}, width = 960 - margin.left - margin.right, height = 500 - margin.top - margin.bottom;
var iconOffset = -10, iconSize = 20;
var mousedown_node = null, mouseup_node = null, mousedown_link = null;
var nodeDeletionActivated = false;
var zoom = d3.behavior.zoom().scaleExtent([0.2, 2]).on("zoom", zoomed);
var svg = d3.select("#topologyArea").append("svg").attr("width", width + margin.left + margin.right).attr("height", height + margin.top + margin.bottom).attr('class', 'background').attr("transform", "translate(" + margin.left + "," + margin.right + ")");
var rect = svg.append("rect").attr("fill","transparent").attr("width", width + margin.left + margin.right).attr("height", height + margin.top + margin.bottom)
.on("mousedown", mousedownOnBackground);
rect.call(zoom);
var elementHolderLayer = svg.append("g");;
var linkLayer, nodeLayer;
d3.select(window).on("keydown", keydown);// add keyboard callback
redraw(elementHolderLayer);
function redraw(theLayer)//after updating the nodes and links arrays, use this function to re-draw the force graph
{
var force = d3.layout.force().size([width, height]).charge(-400).linkDistance(40).on("tick", tick);
var dragElement = force.drag().on("dragstart", dragstarted);
linkLayer = null; nodeLayer = null;
linkLayer = theLayer.selectAll(".link");
nodeLayer = theLayer.selectAll(".node");
linkLayer = linkLayer.data(links, function(d) {return d.id; }).exit().remove();
linkLayer = theLayer.selectAll(".link").data(links, function(d) {return d.id; }).enter().append("line").attr("class", "link");
nodeLayer = nodeLayer.data(nodes, function(d) {return d.id; }).exit().remove();
nodeLayer = theLayer.selectAll(".node").data(nodes, function(d) {return d.id; }).enter().append("circle").attr("class", "node").attr("r", 12)
.on("dblclick", dblclick).style("fill", function(d,i) { return d3.rgb(i*15, i*15, i*15); })
.on("mouseup", function(d,i) { mouseup(d,i);})
.on("mousemove", function(d,i) {mousemove(d,i);})
.on("mousedown", function(d,i) {mousedown(d,i);})
.call(dragElement)
//.classed("dragging", true)
.classed("fixed", function(d) {d.fixed = true;});
force.nodes(nodes).links(links).start();
}//redraw
function tick()
{
linkLayer.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; });
nodeLayer.attr("cx", function(d) {return d.x; }).attr("cy", function(d) { return d.y; });
}
function dblclick(d) { d3.select(this).classed("fixed", d.fixed = false); }
function dragstarted(d)
{
console.log("dragstarted for "+this);
//d3.event.sourceEvent.stopPropagation();
//d3.select(this).classed("dragging", true);
//d3.select(this).classed("fixed", d.fixed = true);
}
function zoomed() { elementHolderLayer.attr("transform", "translate("+d3.event.translate+")scale(" + d3.event.scale + ")"); }
function spliceLinksForNode(node) //remove the links attached to a node that got deleted
{
toSplice = links.filter(function(l) { return (l.source === node) || (l.target === node); });
toSplice.map(function(l) {links.splice(links.indexOf(l), 1); });
}
function keydown()
{
//if (!selected_node && !selected_link) return;
switch (d3.event.keyCode)
{
case 8:
{// backspace
}
case 46:
{ // delete
if (mousedown_node)
{
selected_node = mousedown_node;
if (selected_node)
{
nodes.splice(nodes.indexOf(selected_node), 1);
spliceLinksForNode(selected_node);
}
else if (selected_link) { links.splice(links.indexOf(selected_link), 1); }
selected_link = null;
selected_node = null;
redraw(elementHolderLayer);
}
break;
}
}
}//keydown
function mousedown(d,i) { mousedown_node = d; console.log("mousedown"); }
function mousedownOnBackground() {resetMouseVars();}
function mousemove(d, i) {console.log("mousemove");}
function mouseup(d, i) {console.log("mouseup");}
function resetMouseVars()
{
mousedown_node = null;
mouseup_node = null;
mousedown_link = null;
}
</script>

There is one problem in the redraw function in your code.
linkLayer = linkLayer.data(links, function(d) {return d.id; })
.exit()
.remove();
Above line has no use in your code since you are assigning the same variable with links having the old data again.
linkLayer = theLayer.selectAll(".link").data(links, function(d) { return d.id; })
.enter()
.append("line")
.attr("class", "link");
Same happens for nodes. Change your code as shown below.
//Creating links
linkLayer = theLayer.selectAll(".link").data(links, function(d) {
return d.id;
});
linkLayer.enter().append("line").attr("class", "link");
linkLayer.exit().remove();
//Creating Nodes with image icons
var gNodes = nodeLayer.enter().append("g")
.attr("class", "node")
.on("dblclick", dblclick).style("fill", function(d, i) {
return d3.rgb(i * 15, i * 15, i * 15);
})
.on("mouseup", mouseup)
.on("mousemove", mousemove)
.on("mousedown", mousedown)
.call(dragElement)
.classed("fixed", function(d) {
d.fixed = true;
});
gNodes.append("circle")
.attr("r", 12);
gNodes.append("svg:image")
.attr("class", "circle")
.attr("xlink:href",function(d){ return d.icon })
.attr("x", "-8px")
.attr("y", "-8px")
.attr("width", "16px")
.attr("height", "16px");
nodeLayer.exit().remove();
For updating position of circles and images easily, I have grouped them using g elements. So you will need to update the position of g element using transform attribute instead of updating cx and cy attributes of circle. Now, tick function will look like this. Updated fiddle
function tick() {
linkLayer.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; });
nodeLayer.attr("transform", function(d) {return "translate("+d.x+","+d.y+")"; });
}