Building and Using Tools to See.
UVA Architecture + Data Science. IT Director. Instructor.
Public
Edited
Apr 20, 2024
1 fork
<svg width="400" height="400" viewBox="0 0 400 400">
<style>
.arcArea {stroke: black; stroke-width: 1px; fill: steelblue; opacity: 0.8;}
</style>
<g id="layer1" transform="translate(200,200)"></g>
</svg>
data = ([
{inR:100, outR:120, startAng:0, endAng:60},
{inR:50, outR:60, startAng:60, endAng:145},
{inR:150, outR:180, startAng:60, endAng:145},
{inR:120, outR:165, startAng:145, endAng:220},
{inR:30, outR:150, startAng:265, endAng:275},
{inR:30, outR:120, startAng:275, endAng:285},
{inR:30, outR:200, startAng:285, endAng:295},
{inR:30, outR:90, startAng:295, endAng:305}
])
arcAreasLayer = d3.select(svgContainer).select("#layer1");
arcAreas = {
let arcAreas = arcAreasLayer.selectAll(".arcArea")
.data(data)
.join("path")
.classed("arcArea",true)
.attr("d", d => arcPolygonPath(d.inR, d.outR, d.startAng, d.endAng)); // direct from data or calculate and pass in
return arcAreas;
}
arcPoint = (radius,angle) => {return polarXY(radius+adjust,90-angle)} // example shows starting at 90deg going clockwise (90-angle)
arcPolygonPath = (inR,outR,startAng,endAng) => {
let largeArcFlag = (startAngle,endAngle) => {if (endAngle - startAngle > 180) {return 1} else {return 0}} // largearc calc
let pathString =
"M " + arcPoint(inR,startAng).x + " " + arcPoint(inR,startAng).y + // move to start point
" A " + inR + " " + inR + // draw Arc with x and y radii
" 0" + // rotation of the whole thing, assuming 0
" " + largeArcFlag(startAng,endAng) + // calculate Large Arc Flag (> 180 deg)
" 1 " + // clockwise drawing for the arc (0 or 1)
arcPoint(inR,endAng).x + " " + arcPoint(inR,endAng).y // finish at the end point x,y
+
" L " + arcPoint(outR,endAng).x + " " + arcPoint(outR,endAng).y // line to outer radius at endAngle
+
" A " + outR + " " + outR + // new arc heading back on outside
" 0" +
" " + largeArcFlag(startAng,endAng) +
" 0 " + // counterclockwise this time, going back.
arcPoint(outR,startAng).x + " " + arcPoint(outR,startAng).y
+ " Z"; // close the polygon back to start (line to start)
return pathString;
}
polarXY = (magnitude,angle) => {
magnitude = Number(magnitude);
angle = Number(angle);
let x = magnitude * Math.cos(radiansFromDeg(angle));
let y = -magnitude * Math.sin(radiansFromDeg(angle)); // negative because 0 is at the top
return {"x":x, "y":y};
}
radiansFromDeg = (deg) => {
deg = Number(deg);
return deg * Math.PI / 180;
}
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.
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