Data journalist/designer, Montana
class PointLayer {
constructor(opts) {
// required opts
this.geodata = opts.geodata
this.features = opts.geodata.features
// optional opts
this.featureStyle = opts.featureStyle || {}
this.labelStyle = opts.labelStyle
this.customMarker = opts.customMarker || null
this.hasTooltip = opts.hasTooltip || false
// calculated
this.style = {
radius: d => 2,
opacity: d => 1,
fill: d => '#222',
fillOpacity: d => 1,
stroke: d => null,
strokeWidth: d => 1,
strokeOpacity: d => 1,
...this.featureStyle
}
this.label = {
text: d => null,
fill: d => '#000',
fontSize: d=> '12px',
dx: d => '0.5em',
dy: d => '0.5em',
textAnchor: d => 'start',
...this.labelStyle
}
}
plot(parent, projection, tooltip){
const path = d3.geoPath().projection(projection);
const style = this.style
const label = this.label
// const shapes = parent.append('g').attr('class','feature-layer')
const customMarker = this.customMarker
const markerGroups = parent.append('g').attr('class','feature-layer')
.selectAll('.feature')
.data(this.features).enter()
.append('g')
.attr('transform', d => {
const point = path.centroid(d)
return `translate(${point[0]},${point[1]})`
})
if (customMarker) {
markerGroups.each(customMarker, label)
} else {
markerGroups.append('circle')
.attr('r', (f => style.radius(f.properties)))
.attr('cx', 0)
.attr('cy', 0)
.attr('class', 'feature')
.attr('opacity', (f => style.opacity(f.properties)))
.attr('fill', (f => style.fill(f.properties)))
.attr('fill-opacity', (f => style.fillOpacity(f.properties)))
.attr('stroke', (f => style.stroke(f.properties)))
.attr('stroke-width', (f => style.strokeWidth(f.properties)))
.attr('stroke-opacity', (f => style.strokeOpacity(f.properties)))
}
if (label) {
markerGroups.append('text')
.attr('pointer-events', 'none')
.attr('x',0)
.attr('y',0)
.attr('font-size', f => label.fontSize(f.properties))
.attr('text-anchor', f => label.textAnchor(f.properties))
.attr('dy', f => label.dy(f.properties))
.attr('dx', f => label.dx(f.properties))
.attr('fill', f => label.fill(f.properties))
.text(f => label.text(f.properties))
}
if (this.hasTooltip) {
markerGroups
.on("mouseover", event => tooltip.style("visibility", "visible"))
.on("mousemove", event => updateTooltip(tooltip, event))
.on("mouseout", event => tooltip.style("visibility", "hidden"))
}
}
}
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