Matrix4 transform

The transform from this node's coordinate system to its parent's coordinate system.

By default, the transform is null, which represents the identity transformation (i.e., that this node has the same coorinate system as its parent).

Source 

Matrix4 get transform => _transform;
void transform=(Matrix4 value)

Source 

set transform (Matrix4 value) {
  if (!MatrixUtils.matrixEquals(_transform, value)) {
    _transform = value;
    _markDirty();
  }
}