public override ref PointXYZ At(int col, int row) => ref Unsafe.AsRef <PointXYZ>(Invoke.pointcloud_xyz_at_colrow(_ptr, col, row));
public override ref PointXYZ At(int col, int row) => ref Unsafe.AsRef <PointXYZ>(Invoke.pointcloud_xyz_at_colrow(_ptr, col, row));