alignment-done -- boolean to administrate whether we've done the alignment already (to ensure that the process is done only once)
- group-center-element -- element which will be at the center of the group
- after aligning (when using Align_interface::center_on_element)
+ center-element -- element which will be at the center of the group
+ after aligning (when using
+ Align_interface::center_on_element). The center element should
+ have this object as a reference point.
elements -- to be aligned elements