Sample US Wind Data Viz / Sumant Pattanaik

Sumant Pattanaik

Workspace

Published

Edited

Nov 17, 2020

1 fork

1 star

mColorScale(svgAngle([Math.random(),Math.random()]))

usMap

WIDTH = 500

HEIGHT = 400

projection([ -129.55, 48.38])

processedWindData[0]

{

const f = renderingType == "Canvas"? canvasMap : svgMap;

return f();

}

canvasMap = ()=>{

const projection = d3.geoEquirectangular()

const points = {type: "MultiPoint", coordinates: mData.map(d => [d.longitude, d.latitude])};

const margin = 10;

const [[x0, y0], [x1, y1]] = d3.geoPath(projection.fitWidth(width - margin * 2, points)).bounds(points);

const [tx, ty] = projection.translate();

let height = Math.ceil(y1 - y0);

projection.translate([tx + margin, ty + margin]);

height = height + margin * 2;

const context = DOM.context2d(width, height);

const path = d3.geoPath(projection, context);

context.canvas.style.maxWidth = "100%";

context.fillRect(0, 0, width, height);

context.strokeStyle = "#eee";

context.lineWidth = 1.5;

context.lineJoin = "round";

context.beginPath(), path(mLand), context.stroke();

for (const {longitude, latitude, speed, dir} of mData) {

context.save();

context.translate(...projection([longitude, latitude]));

context.scale(areaScale(speed), areaScale(speed));

context.rotate(dir * Math.PI / 180);

const arrowBaseY = 3;

context.beginPath();

context.moveTo(-2, arrowBaseY);

context.lineTo(2, arrowBaseY);

context.lineTo(0, 8);

context.closePath();

context.fillStyle = colorScale(dir);

context.fill();

context.beginPath();

context.moveTo(0, arrowBaseY);

context.lineTo(0, -2);

context.strokeStyle = colorScale(dir)

context.stroke();

context.restore();

}

return context.canvas;

}

svgMap = ()=>{

const pathGenerator = d3.geoPath().projection(mProjection);

const svg = createSVG(WIDTH,HEIGHT);

svg.append("rect")

.attr("width",WIDTH).attr("height",HEIGHT).style("fill","black");

svg.append("g").append("path").datum(mLand).attr("d",pathGenerator).style("fill","none").style("stroke","#eee");

svgDrawVectorField(svg,mData.map(d=>{const xy=mProjection([d.longitude,d.latitude]); return {x:xy[0], y:xy[1], dir: d.dir, scale: mAreaScale(d.speed), color: mColorScale(d.dir)};}));

return svg.node();

}

createSVG= function(w,h){

return d3.create("svg")

.attr("width", w)

.attr("height", h)

.style("display","block")

}

import {data as mData, projection as mProjection, land as mLand, scale as mAreaScale, color as mColorScale} from "@d3/vector-field"

import {radio} from "@jashkenas/inputs"

import {usMap, margin} from "@spattana/covid-19-update"

d3 = require("d3@5")

One platform to build and deploy the best data apps

Experiment and prototype by building visualizations in live JavaScript notebooks. Collaborate with your team and decide which concepts to build out.

Use Observable Framework to build data apps locally. Use data loaders to build in any language or library, including Python, SQL, and R.

Seamlessly deploy to Observable. Test before you ship, use automatic deploy-on-commit, and ensure your projects are always up-to-date.

Learn more