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JazzTap/.block

Last active October 13, 2017 21:38
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knots from gauss codes - stable branch
Raw
.block
license: gpl-3.0
Raw
index.html
<html>
<head>
<style>
.links path {
fill: none;
stroke-width: 3px;
}
.nodes circle {
fill-opacity: 0.5;
}
</style>
</head>
<body>
<svg id="graph" width="700" height="1000">
</svg>
<script src="//cdnjs.cloudflare.com/ajax/libs/d3/4.1.1/d3.min.js"></script>
<script>
!(function(){
var svg = d3.select("#graph").append("g").attr('transform', 'translate(200 200)')
n = 4
ids = d3.range(0,n).map(function(j){
return [4*j, 4*j+1]
})
ids = [].concat.apply([], ids)
var drawFrom = function(rest) {
// select a random item, and remove it from the deck
i = Math.floor(Math.random()*rest.length)
pick = rest[i]
rest.splice(i,1) // i = rest.indexOf(pick)
// TODO: prevent ports from picking their own up/down mirror
// console.log(rest, pick, i)
return pick
}
// KNOT
crossings = d3.range(0,n).map(function(j){
return {state: 0, // TODO: use 'state' for smoothings
ul: 4*j+2, ur: 4*j+3,
bl: drawFrom(ids), br: drawFrom(ids)}
})
links = crossings.map(function(n, i) {
return [n.ul, n.ur, n.br, n.bl].map(function(goal, corner){
return {target: goal, source: 4*i+corner} })
})
links = Array.prototype.concat.apply([], links)
// FIXME: preserve over/underness of crossings.
// tour links from base points on each knot?
// FIGURE
ports = d3.range(0,4*n).map(function(j){
return {id: j}
})
/* FIXME: given a port, return its successor (link) and predecessor (link) */
fakelinks = d3.range(0,n).map(function(j){
i = 4*j
// TODO: make permutations concise
ln = function(a,b) {return {fake: true,
source: a, target: b}}
return [ln(i,i+1), ln(i,i+2), ln(i,i+3),
ln(i+1,i+2), ln(i+1,i+3), ln(i+2,i+3)]
})
links = Array.prototype.concat.apply(links, fakelinks)
// d3 setup, binding
var simulation = d3.forceSimulation()
.force("link", d3.forceLink().id(function(d) { return d.index }))
// .force("collide",d3.forceCollide( function(d){return d.r + 8 }).iterations(16) )
.force("charge", d3.forceManyBody().strength(-100))
// .force("center", d3.forceCenter(chartWidth / 2, chartWidth / 2))
.force("y", d3.forceY(0))
.force("x", d3.forceX(0))
var port = svg.append("g")
.attr("class", "nodes")
.selectAll("circle").data(ports)
.enter().append("circle")
.attr("r", 10)
.attr("fill", function(d,i) {
return i==0 ? '#511' : i==1 ? '#373' : i==2 ? '#559' :
i%2==0 ? '#aaa' : '#ccc' })
.call(d3.drag()
.on("start", dragstarted)
.on("drag", dragged)
.on("end", dragended));
var link = svg.append("g")
.attr("class", "links")
.selectAll("path").data(links)
.enter().append("svg:path")
.attr("stroke", function(d,k) {
v = d.fake ? 0 :
Math.floor(4 * (4*n - k)/n).toString(16) // \in [0,f]
return d.source==0 ? '#955' : d.source==1 ? '#373' : d.source==2 ? '#559' :
k ? '#'+v+v+v : '#000' })
.attr("stroke-dasharray", function(d) {
return d.fake ? [10,5] : [0,0] })
.attr("stroke-opacity", function(d) {
return d.fake ? .1 : 1 })
.attr("pointer-events", "none")
var overlay = svg.append("g")
.attr("class", "overlay")
.selectAll("circle").data(crossings)
.enter().append("circle")
.attr("r", 30) // TODO: adjust for wide spreads?
.attr("fill", '#99e')
.attr("fill-opacity", .1)
// FIXME: add drag event affecting all ports
.on("click", function(d, i) {
// FIXME: must update incoming edges for horz smoothing,
// else have (3,1) edges and not (2,2) ea. side
out0 = d.state < 2 ? d.br : d.state == 2 ? d.bl : d.ur
out1 = d.state < 2 ? d.bl : d.br
d.state = (d.state + 1) % 4
console.log(d.state, out0, out1)
// TODO: more concise state-switch
if (d.state == 0) { // over
d.ul = 4*i+2; d.ur = 4*i+3;
d.bl = out1; d.br = out0;
}
else if (d.state == 1) { // under (FIXME: implement)
d.ul = 4*i+2; d.ur = 4*i+3;
d.bl = out1; d.br = out0;
}
else if (d.state == 2) { // vert
d.ul = 4*i+3; d.ur = 4*i+2;
d.bl = out0; d.br = out1;
}
else if (d.state == 3) { // horz
d.ul = 4*i+1; d.ur = out0;
d.bl = 4*i+2; d.br = out1;
}
up = [d.ul, d.ur, d.br, d.bl].map(function(goal, corner){
return {target: ports[goal],
source: ports[4*i+corner], idx: i} })
Array.prototype.splice.apply(links, [4*i, 4].concat(up))
// console.log(links[4*i])
console.log(up)
// general update pattern bl.ocks.org/mbostock/1095795
link = link.data(links)
link.exit().remove()
link = link.enter().append("svg:path").merge(link)
ticked()
})
// simulation callback, binding
var ticked = function() {
// elliptical segments: http://stackoverflow.com/a/16371890
link.attr("d", function(d) {
var dx = d.target.x - d.source.x,
dy = d.target.y - d.source.y,
dr = d.fake ? 0 : 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;
});
port
.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; });
var portsIn = function(d,i) {
return d3.range(4*i, 4*i+4).map(function(i) {return ports[i]}) };
overlay
.attr("cx", function(d,i) {
return d3.mean(portsIn(d,i).map(function(u) {return u.x}) ) })
.attr("cy", function(d,i) {
return d3.mean(portsIn(d,i).map(function(u) {return u.y}) ) });
}
simulation
.nodes(ports)
.on("tick", ticked);
simulation
.force("link")
.links(links);
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;
}
}());
</script>
</body>
</html>
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