39 lines
778 B
C
39 lines
778 B
C
/*
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* p2d_contains_poly.c - Determine whether polygon contains other polygon
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*
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* Written 2012 by Werner Almesberger
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* Copyright 2012 Werner Almesberger
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*/
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#include <assert.h>
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#include "poly2d.h"
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int p2d_contains_poly(const struct p2d *a, const struct p2d *b)
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{
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const struct v2d *v;
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int in = 0, out = 0;
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assert(p2d_is_closed(a));
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v = b->v;
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while (v) {
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if (p2d_contains_point(a, v))
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in++;
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else
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out++;
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v = v->next;
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if (v == b->v)
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break;
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}
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if (in && out)
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return -1;
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return !out;
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}
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