add option to initialize heap with a known number of elements, since this may be known in advance - it avoids re-allocing too much.

1 files changed, 9 insertions, 3 deletions

diff --git a/source/blender/blenlib/intern/BLI_heap.c b/source/blender/blenlib/intern/BLI_heap.c
index ee7d93ea1a9..5e0762a5d68 100644
--- a/source/blender/blenlib/intern/BLI_heap.c
+++ b/source/blender/blenlib/intern/BLI_heap.c
@@ -67,16 +67,22 @@ struct Heap {
 
 /***/
 
-Heap *BLI_heap_new(void)
+/* use when the size of the heap is known in advance */
+Heap *BLI_heap_new_ex(unsigned int tot_reserve)
 {
 	Heap *heap = (Heap *)MEM_callocN(sizeof(Heap), __func__);
-	heap->bufsize = 1;
-	heap->tree = (HeapNode **)MEM_mallocN(sizeof(HeapNode *), "BLIHeapTree");
+	heap->bufsize = tot_reserve;
+	heap->tree = (HeapNode **)MEM_mallocN(tot_reserve * sizeof(HeapNode *), "BLIHeapTree");
 	heap->arena = BLI_memarena_new(1 << 16, "heap arena");
 
 	return heap;
 }
 
+Heap *BLI_heap_new(void)
+{
+	return BLI_heap_new_ex(1);
+}
+
 void BLI_heap_free(Heap *heap, HeapFreeFP ptrfreefp)
 {
 	int i;