d3 v4 force layout with boundary - d3.js

Question

I'm trying to create a forceSimulation in d3 v4 which does not let the nodes float outside the boundries of the svg in the same way that this example has it for d3 v3 https://bl.ocks.org/mbostock/1129492.
Have tried a few different things in simulation.on("tick", ticked) to no avail. My codePen is below. Any ideas on how to achieve this?
https://codepen.io/mtsvelik/pen/rzxVrE
//Read the data from the mis element
var graph = document.getElementById('json').innerHTML;
graph = JSON.parse(graph);
render(graph);
function render(graph){
// Dimensions of sunburst.
var radius = 6;
var maxValue = d3.max(graph.links, function(d, i, data) {
return d.value;
});
//sub-in max-value from
d3.select("div").html('<form class="force-control" ng-if="formControl">Link threshold 0 <input type="range" id="thersholdSlider" name="points" value="0" min="0" max="'+ maxValue +'">'+ maxValue +'</form>');
document.getElementById("thersholdSlider").onchange = function() {threshold(this.value);};
var svg = d3.select("svg");
var width = svg.attr("width");
var height = svg.attr("height");
console.log(graph);
var graphRec = JSON.parse(JSON.stringify(graph)); //Add this line
//graphRec = graph; //Add this line
console.log(graphRec);
var simulation = d3.forceSimulation()
.force("link", d3.forceLink().id(function(d) { return d.id; }))
.force("charge", d3.forceManyBody().strength(Number(-1000 + (1.25*graph.links.length)))) //default force is -30, making weaker to increase size of chart
.force("center", d3.forceCenter(width / 2, height / 2));
var link = svg.append("g")
.attr("class", "links")
.selectAll("line")
.data(graph.links)
.enter().append("line")
.attr("class", "link")
.attr("stroke-width", function(d) { return Math.sqrt(d.value); });
var node = svg.append("g")
.attr("class", "nodes")
.selectAll("circle")
.data(graph.nodes)
.enter().append("circle")
.attr("class", "node")
.attr("r", radius)
.attr("fill", function(d) { return d.color; })
.call(d3.drag()
.on("start", dragstarted)
.on("drag", dragged)
.on("end", dragended));
node.append("title")
.text(function(d) { return d.id; });
simulation
.nodes(graph.nodes)
.on("tick", ticked);
simulation.force("link")
.links(graph.links);
console.log(link.data(graph.links));
function ticked() {
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("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; });
}
function dragstarted(d) {
if (!d3.event.active) simulation.alphaTarget(0.3).restart();
d.fx = d.x;
d.fy = d.y;
}
function dragged(d) {
d.fx = d3.event.x;
d.fy = d3.event.y;
}
function dragended(d) {
if (!d3.event.active) simulation.alphaTarget(0);
d.fx = null;
d.fy = null;
}
function threshold(thresh) {
thresh = Number(thresh);
graph.links.splice(0, graph.links.length);
for (var i = 0; i < graphRec.links.length; i++) {
if (graphRec.links[i].value > thresh) {graph.links.push(graphRec.links[i]);}
}
console.log(graph.links);
/*var threshold_links = graph.links.filter(function(d){ return (d.value > thresh);});
console.log(graph.links);
restart(threshold_links);*/
restart();
}
//Restart the visualisation after any node and link changes
// function restart(threshold_links) {
function restart() {
//DATA JOIN
//link = link.data(threshold_links);
link = link.data(graph.links);
console.log(link);
//EXIT
link.exit().remove();
console.log(link);
// ENTER - https://bl.ocks.org/colbenkharrl/21b3808492b93a21de841bc5ceac4e47
// Create new links as needed.
link = link.enter().append("line")
.attr("class", "link")
.attr("stroke-width", function(d) { return Math.sqrt(d.value); }).merge(link);
console.log(link);
// DATA JOIN
node = node.data(graph.nodes);
/*
// EXIT
node.exit().remove();
// ENTER
node = node.enter().append("circle")
.attr("class", "node")
.attr("r", radius)
.attr("fill", function(d) {return d.color;})
.call(d3.drag()
.on("start", dragstarted)
.on("drag", dragged)
.on("end", dragended)
)
.merge(node);
node.append("title")
.text(function(d) { return d.id; });
*/
simulation
.nodes(graph.nodes)
.on("tick", ticked);
simulation.force("link")
.links(graph.links);
simulation.alphaTarget(0.3).restart();
}
}

Answer 1

In the tick function restrict the nodes to move out from the boundary:
node
.attr("cx", function(d) {
return (d.x = Math.max(radius, Math.min(width - radius, d.x)));
})
.attr("cy", function(d) {
return (d.y = Math.max(radius, Math.min(height - radius, d.y)));
})
//now update the links.
working code here

Answer 2

You can also use d3.forceBoundary that allows you to set a boundary with a strength. In your code
import it
<script src="https://unpkg.com/d3-force-boundary#0.0.1/dist/d3-force-boundary.min.js"></script>
then
var simulation = d3.forceSimulation()
.force("boundary", forceBoundary(0,0,width, height))
.force("link", d3.forceLink().id(function(d) { return d.id; }))
.force("charge", d3.forceManyBody().strength(Number(-1000 + (1.25*graph.links.length)))) //default force is -30, making weaker to increase size of chart
.force("center", d3.forceCenter(width / 2, height / 2));
your pen fixed https://codepen.io/duto_guerra/pen/XWXagqm