+static void bh_iter_init_box( i32 root, bh_iter *it, boxf box ){
+ bh_iter_init_generic( root, it );
+ it->query = k_bh_query_box;
+
+ box_copy( box, it->box.box );
+}
+
+static void bh_iter_init_ray( i32 root, bh_iter *it, v3f co,
+ v3f dir, f32 max_dist ){
+ bh_iter_init_generic( root, it );
+ it->query = k_bh_query_ray;
+
+ v3_div( (v3f){1.0f,1.0f,1.0f}, dir, it->ray.inv_dir );
+ v3_copy( co, it->ray.co );
+ it->ray.max_dist = max_dist;
+}
+
+static void bh_iter_init_range( i32 root, bh_iter *it, v3f co, f32 range ){
+ bh_iter_init_generic( root, it );
+ it->query = k_bh_query_range;
+
+ v3_copy( co, it->range.co );
+ it->range.dist_sqr = range*range;
+}
+
+/* NOTE: does not compute anything beyond the leaf level. element level tests
+ * should be implemented by the users code.
+ *
+ * this is like a 'broad phase only' deal.
+ */
+static i32 bh_next( bh_tree *bh, bh_iter *it, i32 *em ){
+ while( it->depth >= 0 ){