From 6aaabf2209a54fde58c16ca328d5bc22eea65a47 Mon Sep 17 00:00:00 2001 From: Tavian Barnes Date: Wed, 25 Jun 2014 20:50:23 -0400 Subject: prtree: Clean up some construction code. --- libdimension/prtree.c | 97 +++++++++++++++++++++++---------------------------- 1 file changed, 43 insertions(+), 54 deletions(-) (limited to 'libdimension') diff --git a/libdimension/prtree.c b/libdimension/prtree.c index 0d484ce..65eb6fa 100644 --- a/libdimension/prtree.c +++ b/libdimension/prtree.c @@ -120,16 +120,16 @@ static dmnsn_array_comparator_fn *const dmnsn_comparators[DMNSN_PSEUDO_B] = { /// Add the priority leaves for this level. static void dmnsn_add_priority_leaves(dmnsn_bvh_node **sorted_leaves[DMNSN_PSEUDO_B], - size_t nleaves, + size_t start, size_t end, dmnsn_array *new_leaves) { for (size_t i = 0; i < DMNSN_PSEUDO_B; ++i) { dmnsn_bvh_node *leaf = NULL; dmnsn_bvh_node **leaves = sorted_leaves[i]; - for (size_t j = 0; - j < nleaves && (!leaf || leaf->nchildren < DMNSN_PRTREE_B); - ++j) - { + + for (size_t j = start; + j < end && (!leaf || leaf->nchildren < DMNSN_PRTREE_B); + ++j) { // Skip all the previously found extreme nodes if (leaves[j]->data == DMNSN_PRTREE_LEAF) { continue; @@ -150,14 +150,12 @@ dmnsn_add_priority_leaves(dmnsn_bvh_node **sorted_leaves[DMNSN_PSEUDO_B], } } +/// Get rid of the extreme nodes. static void -dmnsn_split_sorted_leaves_easy(dmnsn_bvh_node **leaves, - size_t *nleaves, - size_t *nright_leaves) +dmnsn_filter_leaves(dmnsn_bvh_node **leaves, size_t start, size_t *endp) { - // Get rid of the extreme nodes - size_t i, skip, size = *nleaves; - for (i = 0, skip = 0; i < size; ++i) { + size_t i, skip, end; + for (i = start, skip = 0, end = *endp; i < end; ++i) { if (leaves[i]->data == DMNSN_PRTREE_LEAF) { ++skip; } else { @@ -165,28 +163,30 @@ dmnsn_split_sorted_leaves_easy(dmnsn_bvh_node **leaves, } } - size -= skip; + *endp -= skip; +} - // Split the leaves and mark the left and right child nodes - size_t left_size = (size + 1)/2; - for (i = 0; i < left_size; ++i) { +/// Split the leaves and mark the left and right child nodes. +static void +dmnsn_split_sorted_leaves_easy(dmnsn_bvh_node **leaves, size_t start, size_t *midp, size_t end) +{ + size_t i, mid = start + (end - start + 1)/2; + for (i = start; i < mid; ++i) { leaves[i]->data = DMNSN_PRTREE_LEFT; } - for (i = left_size; i < size; ++i) { + for (; i < end; ++i) { leaves[i]->data = DMNSN_PRTREE_RIGHT; } - *nleaves = left_size; - *nright_leaves = size - left_size; + *midp = mid; } +/// Split the leaves using the coloring from dmnsn_split_sorted_leaves_easy(). static void -dmnsn_split_sorted_leaves_hard(dmnsn_bvh_node **leaves, - dmnsn_bvh_node **buffer, - size_t nleaves) +dmnsn_split_sorted_leaves_hard(dmnsn_bvh_node **leaves, dmnsn_bvh_node **buffer, size_t start, size_t mid, size_t end) { size_t i, j, skip; - for (i = 0, j = 0, skip = 0; i < nleaves; ++i) { + for (i = start, j = 0, skip = 0; i < end; ++i) { if (leaves[i]->data == DMNSN_PRTREE_LEFT) { leaves[i - skip] = leaves[i]; } else { @@ -198,34 +198,32 @@ dmnsn_split_sorted_leaves_hard(dmnsn_bvh_node **leaves, } } - size_t left_size = i - skip; for (i = 0; i < j; ++i) { - leaves[left_size + i] = buffer[i]; + leaves[mid + i] = buffer[i]; } } /// Split the sorted lists into the left and right subtrees. static void dmnsn_split_sorted_leaves(dmnsn_bvh_node **sorted_leaves[DMNSN_PSEUDO_B], - size_t *nleaves, - dmnsn_bvh_node **right_sorted_leaves[DMNSN_PSEUDO_B], - size_t *nright_leaves, - dmnsn_bvh_node **buffer, - size_t i) + size_t start, size_t *midp, size_t *endp, + dmnsn_bvh_node **buffer, int i) { - size_t original_size = *nleaves; + size_t orig_end = *endp; + + // Filter the extreme nodes in the ith list + dmnsn_filter_leaves(sorted_leaves[i], start, endp); // Split the ith list - dmnsn_split_sorted_leaves_easy(sorted_leaves[i], nleaves, nright_leaves); + dmnsn_split_sorted_leaves_easy(sorted_leaves[i], start, midp, *endp); // Split the rest of the lists for (size_t j = 0; j < DMNSN_PSEUDO_B; ++j) { - right_sorted_leaves[j] = sorted_leaves[j] + *nleaves; if (j == i) { continue; } - dmnsn_split_sorted_leaves_hard(sorted_leaves[j], buffer, original_size); + dmnsn_split_sorted_leaves_hard(sorted_leaves[j], buffer, start, *midp, orig_end); } } @@ -233,30 +231,24 @@ dmnsn_split_sorted_leaves(dmnsn_bvh_node **sorted_leaves[DMNSN_PSEUDO_B], /// leaves. static void dmnsn_priority_leaves_recursive(dmnsn_bvh_node **sorted_leaves[DMNSN_PSEUDO_B], - size_t nleaves, + size_t start, size_t end, dmnsn_bvh_node **buffer, dmnsn_array *new_leaves, int comparator) { - dmnsn_add_priority_leaves(sorted_leaves, nleaves, new_leaves); + dmnsn_add_priority_leaves(sorted_leaves, start, end, new_leaves); - dmnsn_bvh_node **right_sorted_leaves[DMNSN_PSEUDO_B]; - size_t right_nleaves; + size_t mid; + dmnsn_split_sorted_leaves(sorted_leaves, start, &mid, &end, buffer, comparator); - dmnsn_split_sorted_leaves(sorted_leaves, &nleaves, - right_sorted_leaves, &right_nleaves, - buffer, comparator); + int next = (comparator + 1)%DMNSN_PSEUDO_B; - if (nleaves > 0) { - dmnsn_priority_leaves_recursive(sorted_leaves, nleaves, - buffer, new_leaves, - (comparator + 1)%DMNSN_PSEUDO_B); + if (start < mid) { + dmnsn_priority_leaves_recursive(sorted_leaves, start, mid, buffer, new_leaves, next); } - if (right_nleaves > 0) { - dmnsn_priority_leaves_recursive(right_sorted_leaves, right_nleaves, - buffer, new_leaves, - (comparator + 1)%DMNSN_PSEUDO_B); + if (mid < end) { + dmnsn_priority_leaves_recursive(sorted_leaves, mid, end, buffer, new_leaves, next); } } @@ -275,8 +267,7 @@ dmnsn_sort_leaf_array(dmnsn_bvh_node **leaves, size_t nleaves, int comparator) size_t leaves_size = nleaves*sizeof(dmnsn_bvh_node *); dmnsn_bvh_node **sorted_leaves = dmnsn_malloc(leaves_size); memcpy(sorted_leaves, leaves, leaves_size); - qsort(sorted_leaves, nleaves, sizeof(dmnsn_bvh_node *), - dmnsn_comparators[comparator]); + qsort(sorted_leaves, nleaves, sizeof(dmnsn_bvh_node *), dmnsn_comparators[comparator]); return sorted_leaves; } @@ -286,8 +277,7 @@ dmnsn_sort_leaves(void *ptr, unsigned int thread, unsigned int nthreads) dmnsn_sort_leaves_payload *payload = ptr; for (unsigned int i = thread; i < DMNSN_PSEUDO_B; i += nthreads) { - payload->sorted_leaves[i] = - dmnsn_sort_leaf_array(payload->leaves_arr, payload->nleaves, i); + payload->sorted_leaves[i] = dmnsn_sort_leaf_array(payload->leaves_arr, payload->nleaves, i); } return 0; @@ -319,8 +309,7 @@ dmnsn_priority_leaves(const dmnsn_array *leaves, unsigned int nthreads) dmnsn_array *new_leaves = DMNSN_NEW_ARRAY(dmnsn_bvh_node *); - dmnsn_priority_leaves_recursive(sorted_leaves, nleaves, buffer, new_leaves, - 0); + dmnsn_priority_leaves_recursive(sorted_leaves, 0, nleaves, buffer, new_leaves, 0); dmnsn_free(buffer); for (size_t i = 0; i < DMNSN_PSEUDO_B; ++i) { -- cgit v1.2.3