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Forked from Phrogz/SVG Path to Polygon.js
Created December 21, 2020 16:44
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Convert a SVG path to a Polygon by sampling the path, but also including all control points in the result. See http://phrogz.net/SVG/convert_path_to_polygon.xhtml
// http://phrogz.net/SVG/convert_path_to_polygon.xhtml
function pathToPolygon(path,samples){
if (!samples) samples = 0;
var doc = path.ownerDocument;
var poly = doc.createElementNS('http://www.w3.org/2000/svg','polygon');
// Put all path segments in a queue
for (var segs=[],s=path.pathSegList,i=s.numberOfItems-1;i>=0;--i) segs[i] = s.getItem(i);
var segments = segs.concat();
var seg,lastSeg,points=[],x,y;
var addSegmentPoint = function(s){
if (s.pathSegType == SVGPathSeg.PATHSEG_CLOSEPATH){
}else{
if (s.pathSegType%2==1 && s.pathSegType>1){
// All odd-numbered path types are relative, except PATHSEG_CLOSEPATH (1)
x+=s.x; y+=s.y;
}else{
x=s.x; y=s.y;
}
var lastPoint = points[points.length-1];
if (!lastPoint || x!=lastPoint[0] || y!=lastPoint[1]) points.push([x,y]);
}
};
for (var d=0,len=path.getTotalLength(),step=len/samples;d<=len;d+=step){
var seg = segments[path.getPathSegAtLength(d)];
var pt = path.getPointAtLength(d);
if (seg != lastSeg){
lastSeg = seg;
while (segs.length && segs[0]!=seg) addSegmentPoint( segs.shift() );
}
var lastPoint = points[points.length-1];
if (!lastPoint || pt.x!=lastPoint[0] || pt.y!=lastPoint[1]) points.push([pt.x,pt.y]);
}
for (var i=0,len=segs.length;i<len;++i) addSegmentPoint(segs[i]);
for (var i=0,len=points.length;i<len;++i) points[i] = points[i].join(',');
poly.setAttribute('points',points.join(' '));
return poly;
}
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