From ee6c4aef73df23e0e55f197e259e4bdbddf7c76e Mon Sep 17 00:00:00 2001
From: Tavian Barnes <tavianator@tavianator.com>
Date: Tue, 3 Sep 2013 19:07:12 -0400
Subject: bvh: Store the intersection cache right in the BVH struct.
This saves a lot of complexity and a little bit of time.
---
libdimension/bvh.c | 71 ++++++++++++------------------------------------------
1 file changed, 15 insertions(+), 56 deletions(-)
(limited to 'libdimension')
diff --git a/libdimension/bvh.c b/libdimension/bvh.c
index a038d11..d27f84e 100644
--- a/libdimension/bvh.c
+++ b/libdimension/bvh.c
@@ -1,5 +1,5 @@
/*************************************************************************
- * Copyright (C) 2012 Tavian Barnes <tavianator@tavianator.com> *
+ * Copyright (C) 2012-2013 Tavian Barnes <tavianator@tavianator.com> *
* *
* This file is part of The Dimension Library. *
* *
@@ -41,9 +41,9 @@ dmnsn_new_stupid_bvh(const dmnsn_array *objects)
/* Implementation of opaque dmnsn_bvh type. */
struct dmnsn_bvh {
- dmnsn_array *unbounded; /**< The unbounded objects. */
- dmnsn_array *bounded; /**< The BVH of the bounded objects. */
- size_t id; /**< A unique ID for this BVH. */
+ dmnsn_array *unbounded; /**< The unbounded objects. */
+ dmnsn_array *bounded; /**< The BVH of the bounded objects. */
+ pthread_key_t intersection_cache; /**< The thread-local intersection cache. */
};
/** A flat BVH node for storing in an array for fast pre-order traversal. */
@@ -129,9 +129,6 @@ dmnsn_flatten_bvh(dmnsn_bvh_node *root)
return flat;
}
-static size_t dmnsn_bvh_seq = 0;
-static pthread_mutex_t dmnsn_bvh_seq_mutex = PTHREAD_MUTEX_INITIALIZER;
-
dmnsn_bvh *dmnsn_new_bvh(const dmnsn_array *objects, dmnsn_bvh_kind kind)
{
dmnsn_bvh *bvh = dmnsn_malloc(sizeof(dmnsn_bvh));
@@ -157,9 +154,7 @@ dmnsn_bvh *dmnsn_new_bvh(const dmnsn_array *objects, dmnsn_bvh_kind kind)
dmnsn_delete_bvh_node(root);
dmnsn_delete_array(bounded);
- dmnsn_lock_mutex(&dmnsn_bvh_seq_mutex);
- bvh->id = dmnsn_bvh_seq++;
- dmnsn_unlock_mutex(&dmnsn_bvh_seq_mutex);
+ dmnsn_key_create(&bvh->intersection_cache, dmnsn_free);
return bvh;
}
@@ -168,6 +163,8 @@ void
dmnsn_delete_bvh(dmnsn_bvh *bvh)
{
if (bvh) {
+ dmnsn_free(pthread_getspecific(bvh->intersection_cache));
+ dmnsn_key_delete(bvh->intersection_cache);
dmnsn_delete_array(bvh->bounded);
dmnsn_delete_array(bvh->unbounded);
dmnsn_free(bvh);
@@ -235,60 +232,22 @@ typedef struct dmnsn_intersection_cache {
dmnsn_object *objects[DMNSN_INTERSECTION_CACHE_SIZE];
} dmnsn_intersection_cache;
-/** The thread-specific intersection cache. */
-static pthread_key_t dmnsn_intersection_caches;
-/** Initialize the thread-specific pointer exactly once. */
-static pthread_once_t dmnsn_intersection_caches_once = PTHREAD_ONCE_INIT;
-
-static void
-dmnsn_delete_intersection_caches(void *caches)
-{
- dmnsn_delete_array(caches);
-}
-
-static void
-dmnsn_initialize_intersection_caches(void)
-{
- dmnsn_key_create(&dmnsn_intersection_caches,
- dmnsn_delete_intersection_caches);
-}
-
-static dmnsn_array *
-dmnsn_get_intersection_caches(void)
-{
- dmnsn_once(&dmnsn_intersection_caches_once,
- dmnsn_initialize_intersection_caches);
- return pthread_getspecific(dmnsn_intersection_caches);
-}
-
-/** Needed because pthreads doesn't destroy data from the main thread unless
- it exits with pthread_exit(). */
-DMNSN_DESTRUCTOR static void
-dmnsn_delete_main_intersection_caches(void)
-{
- dmnsn_delete_intersection_caches(dmnsn_get_intersection_caches());
- dmnsn_key_delete(dmnsn_intersection_caches);
-}
-
static dmnsn_intersection_cache *
-dmnsn_get_intersection_cache(size_t id)
+dmnsn_get_intersection_cache(const dmnsn_bvh *bvh)
{
- dmnsn_array *caches = dmnsn_get_intersection_caches();
- if (!caches) {
- caches = dmnsn_new_array(sizeof(dmnsn_intersection_cache));
- dmnsn_setspecific(dmnsn_intersection_caches, caches);
- }
+ dmnsn_intersection_cache *cache
+ = pthread_getspecific(bvh->intersection_cache);
- while (dmnsn_array_size(caches) <= id) {
- dmnsn_array_resize(caches, dmnsn_array_size(caches) + 1);
- dmnsn_intersection_cache *cache = dmnsn_array_last(caches);
+ if (!cache) {
+ cache = dmnsn_malloc(sizeof(dmnsn_intersection_cache));
cache->i = 0;
for (size_t i = 0; i < DMNSN_INTERSECTION_CACHE_SIZE; ++i) {
cache->objects[i] = NULL;
}
+ dmnsn_setspecific(bvh->intersection_cache, cache);
}
- return dmnsn_array_at(caches, id);
+ return cache;
}
/** Test for a closer object intersection than we've found so far. */
@@ -322,7 +281,7 @@ dmnsn_bvh_intersection(const dmnsn_bvh *bvh, dmnsn_line ray,
dmnsn_optimized_line optline = dmnsn_optimize_line(ray);
/* Search the intersection cache */
- dmnsn_intersection_cache *cache = dmnsn_get_intersection_cache(bvh->id);
+ dmnsn_intersection_cache *cache = dmnsn_get_intersection_cache(bvh);
if (dmnsn_unlikely(reset)) {
cache->i = 0;
}
--
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