| 1 | var Shape = require('./generic');
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| 2 |
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| 3 | module.exports = Shape(function(innerRadius, outerRadius, startAngle, endAngle){
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| 4 |
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| 5 | var circle = Math.PI * 2,
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| 6 | radiansPerDegree = Math.PI / 180,
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| 7 | sa = startAngle * radiansPerDegree % circle || 0,
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| 8 | ea = endAngle * radiansPerDegree % circle || 0,
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| 9 | ir = Math.min(innerRadius || 0, outerRadius || 0),
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| 10 | or = Math.max(innerRadius || 0, outerRadius || 0),
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| 11 | a = sa > ea ? circle - sa + ea : ea - sa;
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| 12 |
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| 13 | this.width = this.height = or * 2;
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| 14 | var path = this.path;
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| 15 |
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| 16 | if (a >= circle){
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| 17 |
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| 18 | path.move(0, or).arc(or * 2, 0, or).arc(-or * 2, 0, or);
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| 19 | if (ir) path.move(or - ir, 0).counterArc(ir * 2, 0, ir).counterArc(-ir * 2, 0, ir);
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| 20 |
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| 21 | } else {
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| 22 |
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| 23 | var ss = Math.sin(sa), es = Math.sin(ea),
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| 24 | sc = Math.cos(sa), ec = Math.cos(ea),
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| 25 | ds = es - ss, dc = ec - sc, dr = ir - or,
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| 26 | large = a > Math.PI;
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| 27 |
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| 28 | path.move(or + or * ss, or - or * sc).arc(or * ds, or * -dc, or, or, large).line(dr * es, dr * -ec);
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| 29 | if (ir) path.counterArc(ir * -ds, ir * dc, ir, ir, large);
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| 30 |
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| 31 | }
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| 32 |
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| 33 | path.close();
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| 34 |
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| 35 | }); |
| \ | No newline at end of file |