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greg |
1.1 |
#ifndef lint
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greg |
2.7 |
static const char RCSid[] = "$Id: multisamp.c,v 2.6 2024/04/17 15:07:29 greg Exp $";
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greg |
1.1 |
#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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greg |
2.4 |
#include "copyright.h"
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schorsch |
2.5 |
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#include <stdlib.h>
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greg |
2.3 |
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#include "random.h"
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greg |
2.6 |
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/* Convert 1-dimensional sample to N dimensions */
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greg |
2.3 |
void
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greg |
2.6 |
multisamp(double t[], int n, double r)
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greg |
1.1 |
{
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int j;
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greg |
2.6 |
int i, k;
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greg |
1.1 |
int ti[8];
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double s;
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greg |
2.7 |
while (n > 8)
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t[--n] = frandom();
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greg |
1.1 |
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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greg |
2.6 |
t[i] = (1./256.) * (ti[i] + frandom());
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greg |
1.1 |
}
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