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#ifndef lint
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static const char RCSid[] = "$Id$";
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#endif
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/*
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* Binary space partitioning curve for multidimensional sampling.
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*
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* Written by Christophe Schlick
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*/
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#include "copyright.h"
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#include "random.h"
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void
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multisamp(t, n, r) /* convert 1-dimensional sample to N dimensions */
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double t[]; /* returned N-dimensional vector */
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register int n; /* number of dimensions */
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double r; /* 1-dimensional sample [0,1) */
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{
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int j;
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register int i, k;
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int ti[8];
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double s;
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i = n;
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while (i-- > 0)
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ti[i] = 0;
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j = 8;
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while (j--) {
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k = s = r*(1<<n);
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r = s - k;
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i = n;
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while (i-- > 0)
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ti[i] += ti[i] + ((k>>i) & 1);
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}
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i = n;
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while (i-- > 0)
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t[i] = 1./256. * (ti[i] + frandom());
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}
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