33 lines
593 B
JavaScript
33 lines
593 B
JavaScript
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var windingLine = require("./windingLine");
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var EPSILON = 1e-8;
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function isAroundEqual(a, b) {
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return Math.abs(a - b) < EPSILON;
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}
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function contain(points, x, y) {
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var w = 0;
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var p = points[0];
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if (!p) {
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return false;
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}
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for (var i = 1; i < points.length; i++) {
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var p2 = points[i];
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w += windingLine(p[0], p[1], p2[0], p2[1], x, y);
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p = p2;
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} // Close polygon
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var p0 = points[0];
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if (!isAroundEqual(p[0], p0[0]) || !isAroundEqual(p[1], p0[1])) {
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w += windingLine(p[0], p[1], p0[0], p0[1], x, y);
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}
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return w !== 0;
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}
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exports.contain = contain;
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