+VG_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.
+ */
+VG_STATIC i32 bh_next( bh_tree *bh, bh_iter *it, i32 *em ){