BVH-overlap: add callback to BLI_bvhtree_overlap

The callback checks if 2 nodes intersect (not just their AABB).

Advantages:
- theres no need to allocate overlaps which are later ignored.
- expensive intersection tests will run multi-threaded.

Currently only used for Python API.

1 files changed, 8 insertions, 1 deletions

diff --git a/source/blender/blenlib/BLI_kdopbvh.h b/source/blender/blenlib/BLI_kdopbvh.h
index 9f16b02da33..6fc93ca9cdb 100644
--- a/source/blender/blenlib/BLI_kdopbvh.h
+++ b/source/blender/blenlib/BLI_kdopbvh.h
@@ -74,6 +74,9 @@ typedef void (*BVHTree_NearestPointCallback)(void *userdata, int index, const fl
 /* callback must update hit in case it finds a nearest successful hit */
 typedef void (*BVHTree_RayCastCallback)(void *userdata, int index, const BVHTreeRay *ray, BVHTreeRayHit *hit);
 
+/* callback to check if 2 nodes overlap (use thread if intersection results need to be stored) */
+typedef bool (*BVHTree_OverlapCallback)(void *userdata, int index_a, int index_b, unsigned int thread);
+
 /* callback to range search query */
 typedef void (*BVHTree_RangeQuery)(void *userdata, int index, float dist_sq);
 
@@ -88,8 +91,12 @@ void BLI_bvhtree_balance(BVHTree *tree);
 bool BLI_bvhtree_update_node(BVHTree *tree, int index, const float co[3], const float co_moving[3], int numpoints);
 void BLI_bvhtree_update_tree(BVHTree *tree);
 
+unsigned int BLI_bvhtree_overlap_thread_num(const BVHTree *tree);
+
 /* collision/overlap: check two trees if they overlap, alloc's *overlap with length of the int return value */
-BVHTreeOverlap *BLI_bvhtree_overlap(BVHTree *tree1, BVHTree *tree2, unsigned int *r_overlap_tot);
+BVHTreeOverlap *BLI_bvhtree_overlap(
+        const BVHTree *tree1, const BVHTree *tree2, unsigned int *r_overlap_tot,
+        BVHTree_OverlapCallback callback, void *userdata);
 
 float BLI_bvhtree_getepsilon(const BVHTree *tree);