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@awoodruff

awoodruff/circle_thingy.js

Created October 23, 2015 21:26
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circular dot symbol thing
Raw
circle_thingy.js
var g = symbols.append("g"),
statePath = d3.select( /* selector for the state polygon */ ),
centroid = path.centroid( statePath.datum() );
var total = // whatever the total number of dots is
dotDiameter = 4,
dist = 0,
circumference = 0,
canFit = 1,
count = 0,
angleDelta = 0;
for ( var i=0; i<total; i++ ){
count++;
if ( count > canFit ){
dist += dotDiameter;
circumference = 2 * dist * Math.PI;
canFit = Math.floor( circumference / dotDiameter ),
angleDelta = 2 * Math.PI / canFit;
count = 0;
}
var currentAngle = angleDelta * count;
var x = Math.cos(currentAngle) * dist,
y = Math.sin(currentAngle) * dist;
g.append( "circle" )
.attr("cx",x+dotDiameter/2)
.attr("cy",y+dotDiameter/2)
.attr("r",dotDiameter/2)
.attr("fill","#ccc")
.attr("stroke","#666");
}
g.attr("transform","translate(" + centroid.toString() + ")");
@awoodruff
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Missing the rest of the code for context (and for definitions of variables like symbols), but this is the general form of something that would arrange dot symbols into a kind of spiral/circle.

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