Data and community wrangler
Published
Edited
Oct 20, 2021
4 stars
height =500
projection = d3['geoOrthographic']()
md`## Globes
As a start, render some globes with standard and readily available data.`
sphere = ({type: "Sphere"})
graticule = d3.geoGraticule10()
land = topojson.feature(world, world.objects.land)
versor = require("versor@0.0.3")
topojson = require("topojson-client@3")
top10 = ["Vega","Sirius","Capella","Rigel","Canopus","Arcturus","Procyon","Betelgeuse","Rigil Kentaurus","Achernar"]
md`View the table of the merged data, filtered by top10 stars.`
Inputs.table(starProperties.filter(x=>top10.includes(x.name)))
top10Ids=starProperties.filter(x=>top10.includes(x.name)).map((x)=> x.id)
vl.markPoint() // Make a dot plot
.data(starProperties)
.encode(
vl.size().fieldQ("mag").scale({reverse:"true"}),
vl.color().fieldQ("mag").scale({reverse:"true"}).legend(null),
vl.x().fieldQ("mag").title("Steller magnitude"),
)
.render()
star_globe = {
const context = DOM.context2d(width, height);
const starPath = d3.geoPath(projection, context)
.pointRadius(d => magnitudeScale(d.properties.mag)*2);
// create our color scale
const colorScale = d3.scaleSequential(d3.interpolateRdBu)
context.fillStyle = 'black';
context.fillRect(0, 0, width, height);
stars.features.forEach(star => {
context.beginPath(), starPath(star), context.fillStyle = colorScale(star.properties.bv), context.fill();
});
yield context.canvas;
}
md`Now we can experiment with animation. This globe uses a while loop to infinitely change the radius ie stars.features[x].properties.mag of each of the stars with a Math.sin function`
sparkly_stars = {
const context = DOM.context2d(width, height);
while (true) {
const x = (Math.sin(Date.now() / 1000) + 1) / 2 ;
const starPath = d3.geoPath(projection, context)
.pointRadius(d => magnitudeScale(d.properties.mag*x));
const colorScale = d3.scaleSequential(d3.interpolateRdBu)
context.fillStyle = 'black';
context.fillRect(0, 0, width, height);
stars.features.forEach(star => {
context.beginPath(),
starPath(star),
context.fillStyle = "white",
context.fill();
});
yield context.canvas;
}
}
falling_stars = {
const backgroundColor = "black";
const starPath = d3.geoPath(projection).pointRadius(d => magnitudeScale(d.properties.mag));
const svg = d3.create('svg')
.attr("title", "Map")
.attr('width', width)
.attr('height', height)
svg.append("rect")
.attr("width", width)
.attr("height", height)
.attr('fill', backgroundColor);
const all = svg.selectAll('path')
.data(stars.features)
.join('path')
.attr('d', starPath)
.attr('fill', "white")
.attr('stroke', "black")
.attr('stroke-width', 1)
// View one of the SVG paths in console to
console.log('all',all._groups[0][1])
function starFall() {
all
.transition()
.duration(5000)
.attr("transform", 'translate(0,500), scale(2,2)')
}
starFall();
return svg.node();
}
stars.features[0].geometry.coordinates
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d3 = require("d3@5","d3-interpolate@2")
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