Published
Edited
Jun 14, 2021
1 fork
Importers
30 stars
clerp = ([x0, y0], [x1, y1], t) =>
[x0*(1-t) + x1*t, y0*(1-t) + y1*t]
circle_interp = (a, m, b) => {
const
b_m = csub(b, m),
m_a = csub(m,a),
ab_m = cmul(a, b_m),
bm_a = cmul(b, m_a);
return (t) => cdiv(
clerp(ab_m, bm_a, t),
clerp(b_m, m_a, t));
}
plotarc = () => {
let update;
const
height = 500,
p1 = [width / 5, 200],
p2 = [width / 3, 100],
p3 = [2 * width / 3, 350],
svg = d3.select(DOM.svg(width, height)),
arc = svg.append("path")
.attr("fill", "none")
.attr("stroke-width", "2px")
.attr("stroke", "#79e"),
small_points = svg.append("g")
.selectAll("circle")
.data(Array.from(Array(33), (_,i) => i/32))
.enter().append("circle")
.attr("fill", "#c38")
.attr("r", 3),
point = svg.append("g")
.attr("cursor", "move")
.attr("pointer-events", "all")
.attr("stroke", "transparent")
.attr("stroke-width", 30)
.selectAll("circle")
.data([p1, p2, p3])
.enter().append("circle")
.attr("r", 7)
.attr("fill", "#26b")
.call(d3.drag()
.subject(([x, y]) => ({x, y}))
.on("drag", (d) => {
d[0] = clamp(5, width-5, d3.event.x);
d[1] = clamp(5, height-5, d3.event.y);
update();
}));
update = function update() {
const
parametric_arc = circle_interp(p1, p2, p3),
arc_path = bezpts_to_svgpath(bezeval(
parametric_arc, [0,1], [0,width, 0, height], 0.1));
arc.attr("d", arc_path);
point
.attr("cx", d => d[0])
.attr("cy", d => d[1]);
small_points
.attr("cx", t => parametric_arc(t)[0])
.attr("cy", t => parametric_arc(t)[1]);
}
update();
return svg.node();
}
clamp = (a, b, x) => Math.max(a, Math.min(x, b))
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.