Public
Edited
Oct 5, 2019
31 stars
Hello, PGLiteINSEE ParquetHello, apcachDruidJS workerHello, OrbitWord Tour: 40k words and their friendsHello, spectral.jsHello, petite-vueHello, @thi.ng/grid-iteratorsHello, thumbhashHello, SwissGLHello, QOI (and glitches)Hello, orbHello, cosmographHello, TabulatorUsing d3.blur with PlotMath.cbrtHello debounceColorcetHello, gliiHello, Open MeteoHello, PyWaveletsHello, typesenseHello, libgifHello, kmeans-engineHappy anniversary, Project Gutenberg!Hello, fflateHello, ArchieML!Hello, d3-bboxCollideHello, jsgeoda!Hello, EDTF!Hello, protovis!Hello, placekeyHello, fuse.jsHello, Reorder.jsHello, shadow DOMjszipHello, procedural-glHello, qhullHello, genetic-jsDruidJSHello, Tippy.jsHello, paintWorkletBig πHello, AutoencoderHello, Shakespearean UUIDsHello, ccwt.jsHello, constrainautorHello, talismanHello, polygon-offsetHello p-queueHello async-poolHello rollup-plugin-asciiHello, algebra.jsHello, pixi.jsHello, d3-renderHello zip/unzipCumulative Wikipedia DonationsHTML <details>regl textureHello, npyjsHello protobufHello, pencil touchHello, LOESSHello html2canvaslegra mapscolor2cssHello, ecsy2D point distributions
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Also listed in…
Interpolation
Algorithms
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viewof illo = {
const context = DOM.context2d(width, height, 1),
element = context.canvas;

const X = d3
.scaleLinear()
.domain([0, data.width])
.range([-width / 2, width / 2]),
Y = d3
.scaleLinear()
.domain([0, data.height])
.range([-height / 2, height / 2]),
H = (x, y) => tin.heightAt(Math.round(x), Math.round(y)),
Z = (x, y) => 2 * (H(x, y) - 100);

const illo = (element.value = new Zdog.Illustration({
element,
dragRotate: true,
onDragMove: update,
rotate: { x: Zdog.TAU * -.1 }
}));
const g = new Zdog.Anchor({addTo: illo, rotate: {x: Zdog.TAU / 4}});

for (let i = 0; i < tin.triangles.length; i += 3) {
const p0 = tin.triangles[i],
p1 = tin.triangles[i + 1],
p2 = tin.triangles[i + 2],
x0 = tin.coords[2 * p0],
y0 = tin.coords[2 * p0 + 1],
x1 = tin.coords[2 * p1],
y1 = tin.coords[2 * p1 + 1],
x2 = tin.coords[2 * p2],
y2 = tin.coords[2 * p2 + 1];

new Zdog.Shape({
addTo: g,
path: [
{ x: X(x0), y: Y(y0), z: Z(x0, y0) },
{ x: X(x1), y: Y(y1), z: Z(x1, y1) },
{ x: X(x2), y: Y(y2), z: Z(x2, y2) }
],
color: color(H((x0 + x1 + x2) / 3, (y0 + y1 + y2) / 3)),
stroke: 1,
fill: true
});
}
function update() {
illo.updateRenderGraph();
}
update();
yield element;
}
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{
const context = DOM.context2d(width, height),
scale = width / data.width;

for (let i = 0; i < tin.triangles.length; i += 3) {
const p0 = tin.triangles[i],
p1 = tin.triangles[i + 1],
p2 = tin.triangles[i + 2],
x0 = tin.coords[2 * p0],
y0 = tin.coords[2 * p0 + 1],
x1 = tin.coords[2 * p1],
y1 = tin.coords[2 * p1 + 1],
x2 = tin.coords[2 * p2],
y2 = tin.coords[2 * p2 + 1];

context.beginPath();
context.moveTo(scale * x0, scale * y0);
context.lineTo(scale * x1, scale * y1);
context.lineTo(scale * x2, scale * y2);
context.lineTo(scale * x0, scale * y0);

context.fillStyle = color(
tin.heightAt(
Math.round((x0 + x1 + x2) / 3),
Math.round((y0 + y1 + y2) / 3)
)
);
context.fill();
context.stroke();
}

return context.canvas;
}
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Delatin = (await import('delatin@0.1/index.js?module')).default
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data = fetch(
"https://gist.githubusercontent.com/mbostock/4241134/raw/ee3244eaf405667623241b3d5e1477424623d12b/volcano.json"
).then(d => d.json())
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tin = {
const tin = new Delatin(data.values, data.width, data.height);
tin.run(2);
return tin;
}
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tin.getMaxError()
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color = d3
.scaleSequential(interpolateTerrain)
.domain(d3.extent(data.values))
.nice()
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interpolateTerrain = {
const i0 = d3.interpolateHsvLong(d3.hsv(120, 1, 0.65), d3.hsv(60, 1, 0.9));
const i1 = d3.interpolateHsvLong(d3.hsv(60, 1, 0.9), d3.hsv(0, 0, 0.95));
return t => (t < 0.5 ? i0(t * 2) : i1((t - 0.5) * 2));
}
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height = ((width * data.height) / data.width) | 0
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d3 = require("d3@5", "d3-hsv")
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Zdog = require("zdog@1/dist/zdog.dist.min.js")
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