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rschregle |
1.1 |
/*
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rschregle |
1.2 |
======================================================================
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rschregle |
1.1 |
In-core kd-tree for photon map
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Roland Schregle (roland.schregle@{hslu.ch, gmail.com})
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(c) Fraunhofer Institute for Solar Energy Systems,
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(c) Lucerne University of Applied Sciences and Arts,
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rschregle |
1.2 |
supported by the Swiss National Science Foundation (SNSF, #147053)
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======================================================================
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rschregle |
1.1 |
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rschregle |
1.6 |
$Id: pmapkdt.c,v 1.5 2018/11/08 00:54:07 greg Exp $
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rschregle |
1.1 |
*/
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rschregle |
1.2 |
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rschregle |
1.1 |
#include "pmapdata.h" /* Includes pmapkdt.h */
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#include "source.h"
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greg |
1.5 |
#include "otspecial.h"
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#include "random.h"
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rschregle |
1.1 |
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void kdT_Null (PhotonKdTree *kdt)
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{
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kdt -> nodes = NULL;
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}
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static unsigned long kdT_MedianPartition (const Photon *heap,
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unsigned long *heapIdx,
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unsigned long *heapXdi,
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unsigned long left,
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unsigned long right, unsigned dim)
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/* Returns index to median in heap from indices left to right
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(inclusive) in dimension dim. The heap is partitioned relative to
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median using a quicksort algorithm. The heap indices in heapIdx are
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sorted rather than the heap itself. */
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{
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const float *p;
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unsigned long l, r, lg2, n2, m, n = right - left + 1;
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unsigned d;
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/* Round down n to nearest power of 2 */
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for (lg2 = 0, n2 = n; n2 > 1; n2 >>= 1, ++lg2);
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n2 = 1 << lg2;
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/* Determine median position; this takes into account the fact that
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only the last level in the heap can be partially empty, and that
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it fills from left to right */
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m = left + ((n - n2) > (n2 >> 1) - 1 ? n2 - 1 : n - (n2 >> 1));
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while (right > left) {
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/* Pivot node */
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p = heap [heapIdx [right]].pos;
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l = left;
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r = right - 1;
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/* l & r converge, swapping elements out of order with respect to
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pivot node. Identical keys are resolved by cycling through
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dim. The convergence point is then the pivot's position. */
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do {
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while (l <= r) {
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d = dim;
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while (heap [heapIdx [l]].pos [d] == p [d]) {
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d = (d + 1) % 3;
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| 70 |
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if (d == dim) {
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/* Ignore dupes? */
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error(WARNING, "duplicate keys in photon heap");
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l++;
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break;
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}
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}
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if (heap [heapIdx [l]].pos [d] < p [d])
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l++;
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else break;
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}
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while (r > l) {
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d = dim;
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| 86 |
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while (heap [heapIdx [r]].pos [d] == p [d]) {
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d = (d + 1) % 3;
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if (d == dim) {
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/* Ignore dupes? */
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error(WARNING, "duplicate keys in photon heap");
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r--;
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break;
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}
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}
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if (heap [heapIdx [r]].pos [d] > p [d])
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r--;
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else break;
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}
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/* Swap indices (not the nodes they point to) */
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n2 = heapIdx [l];
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heapIdx [l] = heapIdx [r];
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heapIdx [r] = n2;
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/* Update reverse indices */
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heapXdi [heapIdx [l]] = l;
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heapXdi [n2] = r;
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} while (l < r);
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/* Swap indices of convergence and pivot nodes */
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heapIdx [r] = heapIdx [l];
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heapIdx [l] = heapIdx [right];
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heapIdx [right] = n2;
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/* Update reverse indices */
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heapXdi [heapIdx [r]] = r;
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heapXdi [heapIdx [l]] = l;
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heapXdi [n2] = right;
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| 120 |
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if (l >= m)
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right = l - 1;
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if (l <= m)
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left = l + 1;
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}
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/* Once left & right have converged at m, we have found the median */
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return m;
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}
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static void kdT_Build (Photon *heap, unsigned long *heapIdx,
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unsigned long *heapXdi, const float min [3],
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const float max [3], unsigned long left,
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unsigned long right, unsigned long root)
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/* Recursive part of balancePhotons(..). Builds heap from subarray
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defined by indices left and right. min and max are the minimum resp.
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maximum photon positions in the array. root is the index of the
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current subtree's root, which corresponds to the median's 1-based
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index in the heap. heapIdx are the balanced heap indices. The heap
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is accessed indirectly through these. heapXdi are the reverse indices
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from the heap to heapIdx so that heapXdi [heapIdx [i]] = i. */
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{
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float maxLeft [3], minRight [3];
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Photon rootNode;
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unsigned d;
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/* Choose median for dimension with largest spread and partition
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accordingly */
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const float d0 = max [0] - min [0],
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d1 = max [1] - min [1],
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d2 = max [2] - min [2];
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const unsigned char dim = d0 > d1 ? d0 > d2 ? 0 : 2
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: d1 > d2 ? 1 : 2;
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const unsigned long median = left == right
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? left
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: kdT_MedianPartition(heap, heapIdx, heapXdi,
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left, right, dim);
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/* Place median at root of current subtree. This consists of swapping
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the median and the root nodes and updating the heap indices */
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memcpy(&rootNode, heap + heapIdx [median], sizeof(Photon));
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memcpy(heap + heapIdx [median], heap + root - 1, sizeof(Photon));
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rootNode.discr = dim;
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memcpy(heap + root - 1, &rootNode, sizeof(Photon));
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heapIdx [heapXdi [root - 1]] = heapIdx [median];
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heapXdi [heapIdx [median]] = heapXdi [root - 1];
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heapIdx [median] = root - 1;
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heapXdi [root - 1] = median;
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/* Update bounds for left and right subtrees and recurse on them */
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for (d = 0; d <= 2; d++)
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if (d == dim)
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maxLeft [d] = minRight [d] = rootNode.pos [d];
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else {
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maxLeft [d] = max [d];
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minRight [d] = min [d];
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}
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if (left < median)
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kdT_Build(heap, heapIdx, heapXdi, min, maxLeft, left, median - 1,
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root << 1);
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| 184 |
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if (right > median)
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kdT_Build(heap, heapIdx, heapXdi, minRight, max, median + 1, right,
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(root << 1) + 1);
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}
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void kdT_BuildPhotonMap (struct PhotonMap *pmap)
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| 192 |
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{
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Photon *nodes;
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| 194 |
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unsigned long i;
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| 195 |
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unsigned long *heapIdx, /* Photon index array */
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| 196 |
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*heapXdi; /* Reverse index to heapIdx */
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| 198 |
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/* Allocate kd-tree nodes and load photons from heap file */
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| 199 |
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if (!(nodes = calloc(pmap -> numPhotons, sizeof(Photon))))
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| 200 |
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error(SYSTEM, "failed in-core heap allocation in kdT_BuildPhotonMap");
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| 201 |
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| 202 |
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rewind(pmap -> heap);
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| 203 |
rschregle |
1.2 |
i = fread(nodes, sizeof(Photon), pmap -> numPhotons, pmap -> heap);
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| 204 |
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if (i !=
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| 205 |
rschregle |
1.1 |
pmap -> numPhotons)
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| 206 |
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error(SYSTEM, "failed loading photon heap in kdT_BuildPhotonMap");
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| 207 |
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| 208 |
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pmap -> store.nodes = nodes;
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| 209 |
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heapIdx = calloc(pmap -> numPhotons, sizeof(unsigned long));
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| 210 |
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heapXdi = calloc(pmap -> numPhotons, sizeof(unsigned long));
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| 211 |
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if (!heapIdx || !heapXdi)
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| 212 |
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error(SYSTEM, "failed heap index allocation in kdT_BuildPhotonMap");
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| 213 |
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| 214 |
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/* Initialize index arrays */
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| 215 |
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for (i = 0; i < pmap -> numPhotons; i++)
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| 216 |
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heapXdi [i] = heapIdx [i] = i;
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| 217 |
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| 218 |
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/* Build kd-tree */
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| 219 |
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kdT_Build(nodes, heapIdx, heapXdi, pmap -> minPos, pmap -> maxPos, 0,
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| 220 |
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pmap -> numPhotons - 1, 1);
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| 221 |
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| 222 |
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/* Cleanup */
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| 223 |
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free(heapIdx);
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| 224 |
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free(heapXdi);
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| 225 |
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}
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| 226 |
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| 227 |
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| 228 |
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| 229 |
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int kdT_SavePhotons (const struct PhotonMap *pmap, FILE *out)
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| 230 |
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{
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| 231 |
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unsigned long i, j;
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| 232 |
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Photon *p = (Photon*)pmap -> store.nodes;
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| 234 |
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for (i = 0; i < pmap -> numPhotons; i++, p++) {
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| 235 |
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/* Write photon attributes */
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| 236 |
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for (j = 0; j < 3; j++)
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| 237 |
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putflt(p -> pos [j], out);
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| 238 |
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| 239 |
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/* Bytewise dump otherwise we have portability probs */
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| 240 |
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for (j = 0; j < 3; j++)
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| 241 |
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putint(p -> norm [j], 1, out);
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| 242 |
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| 243 |
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#ifdef PMAP_FLOAT_FLUX
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| 244 |
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for (j = 0; j < 3; j++)
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| 245 |
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putflt(p -> flux [j], out);
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| 246 |
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#else
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| 247 |
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for (j = 0; j < 4; j++)
|
| 248 |
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putint(p -> flux [j], 1, out);
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| 249 |
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#endif
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| 250 |
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| 251 |
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putint(p -> primary, sizeof(p -> primary), out);
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| 252 |
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putint(p -> flags, 1, out);
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| 253 |
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| 254 |
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if (ferror(out))
|
| 255 |
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return -1;
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| 256 |
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}
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| 257 |
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| 258 |
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return 0;
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| 259 |
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}
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| 260 |
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| 261 |
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| 262 |
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| 263 |
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int kdT_LoadPhotons (struct PhotonMap *pmap, FILE *in)
|
| 264 |
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{
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| 265 |
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unsigned long i, j;
|
| 266 |
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Photon *p;
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| 267 |
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| 268 |
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/* Allocate kd-tree based on initialised pmap -> numPhotons */
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| 269 |
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pmap -> store.nodes = calloc(sizeof(Photon), pmap -> numPhotons);
|
| 270 |
|
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if (!pmap -> store.nodes)
|
| 271 |
|
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error(SYSTEM, "failed kd-tree allocation in kdT_LoadPhotons");
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| 272 |
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| 273 |
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/* Get photon attributes */
|
| 274 |
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for (i = 0, p = pmap -> store.nodes; i < pmap -> numPhotons; i++, p++) {
|
| 275 |
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for (j = 0; j < 3; j++)
|
| 276 |
|
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p -> pos [j] = getflt(in);
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| 277 |
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|
| 278 |
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/* Bytewise grab otherwise we have portability probs */
|
| 279 |
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for (j = 0; j < 3; j++)
|
| 280 |
|
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p -> norm [j] = getint(1, in);
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| 281 |
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|
| 282 |
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#ifdef PMAP_FLOAT_FLUX
|
| 283 |
|
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for (j = 0; j < 3; j++)
|
| 284 |
|
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p -> flux [j] = getflt(in);
|
| 285 |
|
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#else
|
| 286 |
|
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for (j = 0; j < 4; j++)
|
| 287 |
|
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p -> flux [j] = getint(1, in);
|
| 288 |
|
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#endif
|
| 289 |
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|
| 290 |
|
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p -> primary = getint(sizeof(p -> primary), in);
|
| 291 |
|
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p -> flags = getint(1, in);
|
| 292 |
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|
| 293 |
|
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if (feof(in))
|
| 294 |
|
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return -1;
|
| 295 |
|
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}
|
| 296 |
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|
| 297 |
|
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return 0;
|
| 298 |
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}
|
| 299 |
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| 300 |
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| 301 |
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| 302 |
|
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void kdT_InitFindPhotons (struct PhotonMap *pmap)
|
| 303 |
|
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{
|
| 304 |
|
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pmap -> squeue.len = pmap -> maxGather + 1;
|
| 305 |
|
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pmap -> squeue.node = calloc(pmap -> squeue.len,
|
| 306 |
|
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sizeof(PhotonSearchQueueNode));
|
| 307 |
|
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if (!pmap -> squeue.node)
|
| 308 |
|
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error(SYSTEM, "can't allocate photon search queue");
|
| 309 |
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}
|
| 310 |
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| 311 |
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| 312 |
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| 313 |
|
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static void kdT_FindNearest (PhotonMap *pmap, const float pos [3],
|
| 314 |
|
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const float norm [3], unsigned long node)
|
| 315 |
|
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/* Recursive part of kdT_FindPhotons(). Locate pmap -> squeue.len nearest
|
| 316 |
|
|
* neighbours to pos with similar normal and return in search queue starting
|
| 317 |
|
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* at pmap -> squeue.node. Note that all heap and queue indices are
|
| 318 |
|
|
* 1-based, but accesses to the arrays are 0-based! */
|
| 319 |
|
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{
|
| 320 |
|
|
Photon *p = (Photon*)pmap -> store.nodes + node - 1;
|
| 321 |
|
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unsigned i, j;
|
| 322 |
|
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/* Signed distance to current photon's splitting plane */
|
| 323 |
|
|
float d = pos [p -> discr] - p -> pos [p -> discr],
|
| 324 |
|
|
d2 = d * d, dv [3];
|
| 325 |
|
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PhotonSearchQueueNode* sq = pmap -> squeue.node;
|
| 326 |
|
|
const unsigned sqSize = pmap -> squeue.len;
|
| 327 |
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|
| 328 |
|
|
/* Search subtree closer to pos first; exclude other subtree if the
|
| 329 |
|
|
distance to the splitting plane is greater than maxDist */
|
| 330 |
|
|
if (d < 0) {
|
| 331 |
|
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if (node << 1 <= pmap -> numPhotons)
|
| 332 |
|
|
kdT_FindNearest(pmap, pos, norm, node << 1);
|
| 333 |
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|
| 334 |
|
|
if (d2 < pmap -> maxDist2 && node << 1 < pmap -> numPhotons)
|
| 335 |
|
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kdT_FindNearest(pmap, pos, norm, (node << 1) + 1);
|
| 336 |
|
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}
|
| 337 |
|
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else {
|
| 338 |
|
|
if (node << 1 < pmap -> numPhotons)
|
| 339 |
|
|
kdT_FindNearest(pmap, pos, norm, (node << 1) + 1);
|
| 340 |
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|
| 341 |
|
|
if (d2 < pmap -> maxDist2 && node << 1 <= pmap -> numPhotons)
|
| 342 |
|
|
kdT_FindNearest(pmap, pos, norm, node << 1);
|
| 343 |
|
|
}
|
| 344 |
|
|
|
| 345 |
|
|
/* Reject photon if normal faces away (ignored for volume photons) with
|
| 346 |
|
|
* tolerance to account for perturbation; note photon normal is coded
|
| 347 |
|
|
* in range [-127,127], hence we factor this in */
|
| 348 |
|
|
if (norm && DOT(norm, p -> norm) <= PMAP_NORM_TOL * 127 * frandom())
|
| 349 |
|
|
return;
|
| 350 |
|
|
|
| 351 |
rschregle |
1.3 |
if (isContribPmap(pmap)) {
|
| 352 |
|
|
/* Lookup in contribution photon map; filter according to emitting
|
| 353 |
|
|
* light source if contrib list set, else accept all */
|
| 354 |
|
|
|
| 355 |
|
|
if (pmap -> srcContrib) {
|
| 356 |
|
|
OBJREC *srcMod;
|
| 357 |
|
|
const int srcIdx = photonSrcIdx(pmap, p);
|
| 358 |
|
|
|
| 359 |
|
|
if (srcIdx < 0 || srcIdx >= nsources)
|
| 360 |
|
|
error(INTERNAL, "invalid light source index in photon map");
|
| 361 |
|
|
|
| 362 |
|
|
srcMod = findmaterial(source [srcIdx].so);
|
| 363 |
|
|
|
| 364 |
|
|
/* Reject photon if contributions from light source which emitted it
|
| 365 |
|
|
* are not sought */
|
| 366 |
|
|
if (!lu_find(pmap -> srcContrib, srcMod -> oname) -> data)
|
| 367 |
|
|
return;
|
| 368 |
|
|
}
|
| 369 |
rschregle |
1.1 |
|
| 370 |
|
|
/* Reject non-caustic photon if lookup for caustic contribs */
|
| 371 |
|
|
if (pmap -> lookupCaustic & !p -> caustic)
|
| 372 |
|
|
return;
|
| 373 |
|
|
}
|
| 374 |
|
|
|
| 375 |
|
|
/* Squared distance to current photon (note dist2() requires doubles) */
|
| 376 |
|
|
VSUB(dv, pos, p -> pos);
|
| 377 |
|
|
d2 = DOT(dv, dv);
|
| 378 |
|
|
|
| 379 |
|
|
/* Accept photon if closer than current max dist & add to priority queue */
|
| 380 |
|
|
if (d2 < pmap -> maxDist2) {
|
| 381 |
|
|
if (pmap -> squeue.tail < sqSize) {
|
| 382 |
|
|
/* Priority queue not full; append photon and restore heap */
|
| 383 |
|
|
i = ++pmap -> squeue.tail;
|
| 384 |
|
|
|
| 385 |
|
|
while (i > 1 && sq [(i >> 1) - 1].dist2 <= d2) {
|
| 386 |
|
|
sq [i - 1].idx = sq [(i >> 1) - 1].idx;
|
| 387 |
|
|
sq [i - 1].dist2 = sq [(i >> 1) - 1].dist2;
|
| 388 |
|
|
i >>= 1;
|
| 389 |
|
|
}
|
| 390 |
|
|
|
| 391 |
|
|
sq [--i].idx = (PhotonIdx)p;
|
| 392 |
|
|
sq [i].dist2 = d2;
|
| 393 |
|
|
/* Update maxDist if we've just filled the queue */
|
| 394 |
|
|
if (pmap -> squeue.tail >= pmap -> squeue.len)
|
| 395 |
|
|
pmap -> maxDist2 = sq [0].dist2;
|
| 396 |
|
|
}
|
| 397 |
|
|
else {
|
| 398 |
|
|
/* Priority queue full; replace maximum, restore heap, and
|
| 399 |
|
|
update maxDist */
|
| 400 |
|
|
i = 1;
|
| 401 |
|
|
|
| 402 |
|
|
while (i <= sqSize >> 1) {
|
| 403 |
|
|
j = i << 1;
|
| 404 |
|
|
if (j < sqSize && sq [j - 1].dist2 < sq [j].dist2)
|
| 405 |
|
|
j++;
|
| 406 |
|
|
if (d2 >= sq [j - 1].dist2)
|
| 407 |
|
|
break;
|
| 408 |
|
|
sq [i - 1].idx = sq [j - 1].idx;
|
| 409 |
|
|
sq [i - 1].dist2 = sq [j - 1].dist2;
|
| 410 |
|
|
i = j;
|
| 411 |
|
|
}
|
| 412 |
|
|
|
| 413 |
|
|
sq [--i].idx = (PhotonIdx)p;
|
| 414 |
|
|
sq [i].dist2 = d2;
|
| 415 |
|
|
pmap -> maxDist2 = sq [0].dist2;
|
| 416 |
|
|
}
|
| 417 |
|
|
}
|
| 418 |
|
|
}
|
| 419 |
|
|
|
| 420 |
|
|
|
| 421 |
|
|
|
| 422 |
rschregle |
1.6 |
int kdT_FindPhotons (struct PhotonMap *pmap, const FVECT pos,
|
| 423 |
|
|
const FVECT norm)
|
| 424 |
rschregle |
1.1 |
{
|
| 425 |
|
|
float p [3], n [3];
|
| 426 |
|
|
|
| 427 |
|
|
/* Photon pos & normal stored at lower precision */
|
| 428 |
|
|
VCOPY(p, pos);
|
| 429 |
rschregle |
1.4 |
if (norm)
|
| 430 |
|
|
VCOPY(n, norm);
|
| 431 |
|
|
kdT_FindNearest(pmap, p, norm ? n : NULL, 1);
|
| 432 |
rschregle |
1.6 |
|
| 433 |
|
|
/* Return success or failure (empty queue => none found) */
|
| 434 |
|
|
return pmap -> squeue.tail ? 0 : -1;
|
| 435 |
rschregle |
1.1 |
}
|
| 436 |
|
|
|
| 437 |
|
|
|
| 438 |
|
|
|
| 439 |
|
|
static void kdT_Find1Nearest (PhotonMap *pmap, const float pos [3],
|
| 440 |
|
|
const float norm [3], Photon **photon,
|
| 441 |
|
|
unsigned long node)
|
| 442 |
|
|
/* Recursive part of kdT_Find1Photon(). Locate single nearest neighbour to
|
| 443 |
|
|
* pos with similar normal. Note that all heap and queue indices are
|
| 444 |
|
|
* 1-based, but accesses to the arrays are 0-based! */
|
| 445 |
|
|
{
|
| 446 |
|
|
Photon *p = (Photon*)pmap -> store.nodes + node - 1;
|
| 447 |
|
|
/* Signed distance to current photon's splitting plane */
|
| 448 |
|
|
float d = pos [p -> discr] - p -> pos [p -> discr], d2 = d * d,
|
| 449 |
|
|
dv [3];
|
| 450 |
|
|
|
| 451 |
|
|
/* Search subtree closer to pos first; exclude other subtree if the
|
| 452 |
|
|
distance to the splitting plane is greater than maxDist */
|
| 453 |
|
|
if (d < 0) {
|
| 454 |
|
|
if (node << 1 <= pmap -> numPhotons)
|
| 455 |
|
|
kdT_Find1Nearest(pmap, pos, norm, photon, node << 1);
|
| 456 |
|
|
|
| 457 |
|
|
if (d2 < pmap -> maxDist2 && node << 1 < pmap -> numPhotons)
|
| 458 |
|
|
kdT_Find1Nearest(pmap, pos, norm, photon, (node << 1) + 1);
|
| 459 |
|
|
}
|
| 460 |
|
|
else {
|
| 461 |
|
|
if (node << 1 < pmap -> numPhotons)
|
| 462 |
|
|
kdT_Find1Nearest(pmap, pos, norm, photon, (node << 1) + 1);
|
| 463 |
|
|
|
| 464 |
|
|
if (d2 < pmap -> maxDist2 && node << 1 <= pmap -> numPhotons)
|
| 465 |
|
|
kdT_Find1Nearest(pmap, pos, norm, photon, node << 1);
|
| 466 |
|
|
}
|
| 467 |
|
|
|
| 468 |
|
|
/* Squared distance to current photon */
|
| 469 |
|
|
VSUB(dv, pos, p -> pos);
|
| 470 |
|
|
d2 = DOT(dv, dv);
|
| 471 |
|
|
|
| 472 |
|
|
if (d2 < pmap -> maxDist2 &&
|
| 473 |
rschregle |
1.4 |
(!norm || DOT(norm, p -> norm) > PMAP_NORM_TOL * 127 * frandom())) {
|
| 474 |
rschregle |
1.1 |
/* Closest photon so far with similar normal. We allow for tolerance
|
| 475 |
|
|
* to account for perturbation in the latter; note the photon normal
|
| 476 |
|
|
* is coded in the range [-127,127], hence we factor this in */
|
| 477 |
|
|
pmap -> maxDist2 = d2;
|
| 478 |
|
|
*photon = p;
|
| 479 |
|
|
}
|
| 480 |
|
|
}
|
| 481 |
|
|
|
| 482 |
|
|
|
| 483 |
|
|
|
| 484 |
rschregle |
1.6 |
int kdT_Find1Photon (struct PhotonMap *pmap, const FVECT pos,
|
| 485 |
|
|
const FVECT norm, Photon *photon)
|
| 486 |
rschregle |
1.1 |
{
|
| 487 |
|
|
float p [3], n [3];
|
| 488 |
rschregle |
1.6 |
Photon *pnn = NULL;
|
| 489 |
rschregle |
1.1 |
|
| 490 |
|
|
/* Photon pos & normal stored at lower precision */
|
| 491 |
|
|
VCOPY(p, pos);
|
| 492 |
rschregle |
1.4 |
if (norm)
|
| 493 |
|
|
VCOPY(n, norm);
|
| 494 |
rschregle |
1.6 |
kdT_Find1Nearest(pmap, p, norm ? n : NULL, &pnn, 1);
|
| 495 |
|
|
if (!pnn)
|
| 496 |
|
|
/* No photon found => failed */
|
| 497 |
|
|
return -1;
|
| 498 |
|
|
else {
|
| 499 |
|
|
/* Copy found photon => successs */
|
| 500 |
|
|
memcpy(photon, pnn, sizeof(Photon));
|
| 501 |
|
|
return 0;
|
| 502 |
|
|
}
|
| 503 |
rschregle |
1.1 |
}
|
| 504 |
|
|
|
| 505 |
|
|
|
| 506 |
|
|
|
| 507 |
|
|
int kdT_GetPhoton (const struct PhotonMap *pmap, PhotonIdx idx,
|
| 508 |
|
|
Photon *photon)
|
| 509 |
|
|
{
|
| 510 |
|
|
memcpy(photon, idx, sizeof(Photon));
|
| 511 |
|
|
return 0;
|
| 512 |
|
|
}
|
| 513 |
|
|
|
| 514 |
|
|
|
| 515 |
|
|
|
| 516 |
|
|
Photon *kdT_GetNearestPhoton (const PhotonSearchQueue *squeue, PhotonIdx idx)
|
| 517 |
|
|
{
|
| 518 |
|
|
return idx;
|
| 519 |
|
|
}
|
| 520 |
|
|
|
| 521 |
|
|
|
| 522 |
|
|
|
| 523 |
|
|
PhotonIdx kdT_FirstPhoton (const struct PhotonMap* pmap)
|
| 524 |
|
|
{
|
| 525 |
|
|
return pmap -> store.nodes;
|
| 526 |
|
|
}
|
| 527 |
|
|
|
| 528 |
|
|
|
| 529 |
|
|
|
| 530 |
|
|
void kdT_Delete (PhotonKdTree *kdt)
|
| 531 |
|
|
{
|
| 532 |
|
|
free(kdt -> nodes);
|
| 533 |
|
|
kdt -> nodes = NULL;
|
| 534 |
|
|
}
|
