Type JavaScript, then Shift-Enter. Ctrl-space for more options. Arrow ↑/↓ to switch modes.
class SquareMapChart {
create(classicalWorld, squaredWorld) {
this.width = 960;
this.height = 500;
this.margin = {top: 0, left: 0, right: 0, bottom: 0}
this.world = classicalWorld;
this.worldTile = squaredWorld;
this.svg = d3.select(DOM.svg(
this.width - (this.margin.left + this.margin.right),
this.height - (this.margin.top + this.margin.bottom)
));
this.main = this.svg.append('g')
.attr('class', 'main')
.attr('transform', `translate(${this.margin.left},${this.margin.top})`);
this.map = this.main.append('g')
.attr('class', 'map');
this.labels = this.main.append('g')
.attr('class', 'labels');
}
update(state) {
this.valueAccessor = state.valueAccessor;
this.countryCodeType = state.countryCodeType;
this.countryCodeAccessor = state.countryCodeAccessor;
if(state.data && JSON.stringify(this.data) !== JSON.stringify(state.data)) {
this._drawMap(state.data);
}
if(state.view && this.view !== state.view){
if(state.view === 'classic'){
this.switchToClassic();
} else {
this.switchToSquares();
}
}
this.data = state.data;
this.view = state.view;
return this.svg.node();
}
_drawMap(data) {
const dataDomain = d3.extent(data, d => d[this.valueAccessor]);
const dataMapping = data.reduce( (agg, v) => {
var country;
if(this.countryCodeType === 'name'){
country = this.worldTile.find( d => d.name === v[this.countryCodeAccessor])
}
if(country) agg[country.alpha2] = v[this.valueAccessor];
return agg;
}, {});
var colorScale = d3.scaleSequential()
.domain([dataDomain[1], dataDomain[0]])
.interpolator(d3.interpolateGnBu);
// create a first guess for the projection
var projection = d3.geoNaturalEarth1()
.scale(0.9)
.translate([0, 0]);
// create the path
var path = d3.geoPath()
.projection(projection);
// using the path determine the bounds of the current map and use
// these to determine better values for the scale and translation
var bounds = path.bounds(this.world);
var scale = .95 / Math.max(
(bounds[1][0] - bounds[0][0]) / this.width,
(bounds[1][1] - bounds[0][1]) / this.height
);
var xGridDomain = d3.extent(this.worldTile, d => d.x);
var yGridDomain = d3.extent(this.worldTile, d => d.y);
var xWidth = this.width/(xGridDomain[1] - xGridDomain[0]);
var yWidth = this.height/(yGridDomain[1] - yGridDomain[0]);
var squareWidth = Math.min(xWidth, yWidth);
var xOffset = (this.width - ((xGridDomain[1] - xGridDomain[0])*squareWidth))/2;
var yOffset = (this.height - ((yGridDomain[1] - yGridDomain[0])*squareWidth))/2;
var squarePosition = this.worldTile.reduce( (agg, v) => {
agg[v.alpha2] = {
x: (v.x * squareWidth) + xOffset,
y: (v.y * squareWidth) + yOffset
}
return agg;
}, {})
var offset = [
(this.width - scale * (bounds[1][0] + bounds[0][0])) / 2,
(this.height - scale * (bounds[1][1] + bounds[0][1])) / 2
];
// new projection
projection = d3.geoNaturalEarth1()
.scale(scale)
.translate(offset);
path = path.projection(projection);
this.squarePosition = squarePosition;
this.squareWidth = squareWidth;
this.path = path;
this.map
.selectAll('path')
.data(this.world.features)
.enter().append('path')
.attr('d', path)
.style('fill', d => dataMapping[d.properties.iso_a2] !== undefined ?
colorScale(dataMapping[d.properties.iso_a2]) : '#F0F0F0')
.style('stroke', 'gray')
.style('stroke-width', 1);
this.labels
.selectAll('text')
.data(this.world.features)
.enter().append('text')
.text( d => d.properties.iso_a2 )
.attr('x', d => this.squarePosition[d.properties.iso_a2].x + (this.squareWidth/2) )
.attr('y', d => this.squarePosition[d.properties.iso_a2].y + (this.squareWidth/2) )
.style('fill', 'black')
.style('alignment-baseline', 'central')
.style('text-anchor', 'middle')
.style('font-size', '10px')
.style('font-family', 'Helvetica, Arial, sans-serif')
.style('opacity', 0);
}
switchToSquares(){
this.map
.selectAll('path')
.transition()
.duration(3000)
.attrTween('d', d => {
if(this.squarePosition[d.properties.iso_a2]){
var x = this.squarePosition[d.properties.iso_a2].x;
var y = this.squarePosition[d.properties.iso_a2].y;
if(d.geometry.type === 'MultiPolygon'){
var square = [[x,y], [x+this.squareWidth,y], [x+this.squareWidth,y+this.squareWidth], [x,y+this.squareWidth], [x,y]];
var filteredPolygons = d.geometry.coordinates.map( coordinates => this.path({type: 'Polygon', coordinates: coordinates}));
return flubber.combine(filteredPolygons, square, { single: true });
} else {
return flubber.toRect(this.path(d), x, y, this.squareWidth, this.squareWidth, { maxSegmentLength: 10 });
}
} else {
console.log('Unmatched country ' + d.properties.iso_a2);
return null;
}
})
.transition()
.duration(0)
.attr('d', d => {
if(this.squarePosition[d.properties.iso_a2]){
var x = this.squarePosition[d.properties.iso_a2].x;
var y = this.squarePosition[d.properties.iso_a2].y;
var square = [[x,y], [x+this.squareWidth,y], [x+this.squareWidth,y+this.squareWidth], [x,y+this.squareWidth], [x,y]];
return flubber.toPathString(square);
}
});
this.labels
.selectAll('text')
.transition()
.duration(1000)
.delay(2000)
.style('opacity', 1);
}
switchToClassic(){
this.map
.selectAll('path')
.transition()
.duration(3000)
.attrTween('d', d => {
if(this.squarePosition[d.properties.iso_a2]){
var x = this.squarePosition[d.properties.iso_a2].x;
var y = this.squarePosition[d.properties.iso_a2].y;
if(d.geometry.type === 'MultiPolygon'){
var square = [[x,y], [x+this.squareWidth,y], [x+this.squareWidth,y+this.squareWidth], [x,y+this.squareWidth], [x,y]];
var filteredPolygons = d.geometry.coordinates.map( coordinates => this.path({type: 'Polygon', coordinates: coordinates}));
return flubber.separate(square, filteredPolygons, { single: true });
} else {
return flubber.fromRect(x, y, this.squareWidth, this.squareWidth, this.path(d), { maxSegmentLength: 10 });
}
} else {
console.log('Unmatched country ' + d.properties.iso_a2);
return null;
}
});
this.labels
.selectAll('text')
.transition()
.duration(300)
.style('opacity', 0);
}
}
Type JavaScript, then Shift-Enter. Ctrl-space for more options. Arrow ↑/↓ to switch modes.
Type JavaScript, then Shift-Enter. Ctrl-space for more options. Arrow ↑/↓ to switch modes.
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