load method

RBushBase<T> load(Iterable<T> items)

Bulk loads items into this r-tree. This method returns this to allow for this chaining: RBushBase().load([...])

Implementation

RBushBase<T> load(Iterable<T> items) {
  if (items.isEmpty) return this;

  if (items.length < _minEntries) {
    for (final item in items) insert(item);
    return this;
  }

  // recursively build the tree with the given data from scratch using OMT algorithm
  _RBushNode<T> node = _build(List.of(items), 0, items.length - 1, 0);

  if (data.childrenLength == 0) {
    // save as is if tree is empty
    data = node;
  } else if (data.height == node.height) {
    // split root if trees have the same height
    _splitRoot(data, node);
  } else {
    if (data.height < node.height) {
      // swap trees if inserted one is bigger
      final tmpNode = data;
      data = node;
      node = tmpNode;
    }

    // insert the small tree into the large tree at appropriate level
    _insert(data.height - node.height - 1, inode: node);
  }

  return this;
}