voronoi.cellPolygon(debugCell)
cells = {
const cells = [...voronoi.cellPolygons()].map((cell, i)=>{
return {
id: i,
centroid: centroids[i],
neighbors: [...voronoi.neighbors(i)],
area: Math.abs(d3.polygonArea(cell)),
distance: Infinity,
r: null,
// cell: cell,
}
})
const rank = {
raw: cells,
neighborRank: Array.from(cells).sort((a,b)=>d3.descending(a.neighbors.length, b.neighbors.length)),
areaRank: Array.from(cells).sort((a,b)=>d3.descending(a.area, b.area))
}
function calculateDistance(){
const queue = []
queue.push(rank.neighborRank[0])
rank.neighborRank[0].distance = 0
while (queue.length > 0){
const cell = queue.shift()
for (let n of cell.neighbors){
if (cells[n].distance > cell.distance+1){
cells[n].distance = cell.distance + 1
queue.push(cells[n])
cells[n].r = cell.id
}
}
}
rank['distanceRank'] = Array.from(cells).sort((a,b) => d3.descending(a.distance, b.distance))
}
calculateDistance()
return rank
}
centroids = [...voronoi.cellPolygons()].map(it=> d3.polygonCentroid(it))
svg = {
const svg = d3.create("svg")
.attr("width", mapSize.width)
.attr("height", mapSize.height)
.attr("viewBox", [-mapSize.width / 2 -50, -mapSize.height / 2 -50, mapSize.width +100, mapSize.height +100])
.attr("style", "max-width: 100%; height: auto; height: intrinsic;");
const [hide, show, solo] = ['Hide', 'Show', 'Solo']
const nosolo = Object.values(layers).filter(it=> it === "Solo").length === 0
const points = delaunay.points
if (layers.cells === solo || (nosolo && layers.cells === show)){
const voi = svg.append('g').selectAll('path').data(d3.range(rawPoints.length)).join('path')
.attr('fill', d=>{
if (tags[d].includes('Industry')) return 'tan'
if (tags[d].includes('Commercial')) return 'lightblue'
if (tags[d].includes('Residential')) return 'limegreen'
if (tags[d].includes('Outskirts')) return 'lightyellow'
if (tags[d].includes('Corporations')) return 'steelblue'
if (tags[d].includes('Downtown')) return 'gold'
return 'transparent'
})
.attr('d', d => voronoi.renderCell(d))
}
if (layers.debug === solo || (nosolo && layers.debug === show)){
const debugNeighbors = voronoi.neighbors(debugCell)
const debug = svg.append('g')
debug.append('path')
.attr('fill', 'darkgray')
.attr('d', voronoi.renderCell(debugCell))
debug.append('path')
.attr('fill', 'lightgray')
.attr('d', [...debugNeighbors].map(it=>voronoi.renderCell(it)).join(' '))
}
if (layers.cells === solo || (nosolo && layers.cells === show)){
const voi = svg.append('path')
.attr('stroke', 'gray')
.attr('d', voronoi.render())
}
if (layers.links === solo || (nosolo && layers.links === show)){
const lines = svg.append('g')
.selectAll('line').data(links).join('line')
.attr('stroke', 'cyan')
.attr('stroke-width', '2px')
.attr('x1', d=>points[d.source*2])
.attr('y1', d=>points[d.source*2+1])
.attr('x2', d=>points[d.target*2])
.attr('y2', d=>points[d.target*2+1])
}
// dots should be on top
if (layers.raw === solo || (nosolo && layers.raw === show)){
svg.append('g')
.attr('fill', 'gray')
.selectAll('circle').data(rawPoints).join('circle')
.attr('cx', d=>d.x)
.attr('cy', d=>d.y)
.attr('r', 2)
}
if (layers.relaxed === solo || (nosolo && layers.relaxed === show)){
const dots = svg.append('path')
.attr('d', delaunay.renderPoints())
}
if (layers.centroids === solo || (nosolo && layers.centroids === show)){
svg.append('g')
.attr('fill', 'transparent')
.attr('stroke', 'blue')
.attr('stroke-width', '1')
.selectAll('circle').data(centroids).join('circle')
.attr('cx', d=>d[0])
.attr('cy', d=>d[1])
.attr('r', 3)
// index label
svg.append('g')
.attr('text-anchor', 'middle')
.selectAll('text').data(centroids).join('text')
.attr('x', d=>d[0])
.attr('y', d=>d[1]-8)
.text((d,i)=> i+": "+ tags[i].join(', '))
}
return svg
}
links = {
ticks
const links = []
for(let i = 0; i<n; i++){
for (let neighbor of voronoi.neighbors(i)){
if (neighbor <= i) continue
links.push({
source: i,
target: neighbor,
})
}
}
return links
}
relax = (type = 1) => {
// we have two options here,
// 1. iterate every points and relax it
// 2. iterate links and only relax those whose length exceeds cetain value.
function relax(delaunay, voronoi, i, o = omega) {
const points = delaunay.points;
const cell = voronoi.cellPolygon(i);
if (cell === null) return;
const center = d3.polygonCentroid(cell);
const old = [points[i * 2], points[i * 2 + 1]];
const newPos = calcRelaxedPos(old[0], old[1], center[0], center[1], o);
points[i * 2] = newPos[0];
points[i * 2 + 1] = newPos[1];
}
function calcRelaxedPos(x1, y1, x2, y2, omega) {
return [x1 + (x2 - x1) * omega, y1 + (y2 - y1) * omega];
}
function dot(x1, y1, x2, y2) {
return x1 * x2 + y1 * y2;
}
if (type === 1) {
// 1.
const points = delaunay.points;
for (let i = 0; i < n; i++) {
relax(delaunay, voronoi, i);
}
} else {
// 2.
const points = delaunay.points;
for (let i = 0; i < n; i++) {
for (let neighbor of voronoi.neighbors(i)) {
if (neighbor <= i) continue;
const [x1, y1] = [points[i * 2], points[i * 2 + 1]];
const [x2, y2] = [points[neighbor * 2], points[neighbor * 2 + 1]];
if (dot(x2 - x1, y2 - y1, x2 - x1, y2 - y1) > mindistance**2) {
continue;
}
relax(delaunay, voronoi, i, omega / 2);
relax(delaunay, voronoi, neighbor, omega / 2);
}
}
}
voronoi.update();
}
delaunay = d3.Delaunay.from(rawPoints, d=>d.x, d=>d.y);
voronoi = delaunay.voronoi([-mapSize.width/2, -mapSize.height/2, mapSize.width/2, mapSize.height/2])
mapSize = {
return {
width: 800,
height: 800
}
}
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