We have observed that users sometimes get confused by the mirror functionality which doubles the geometry by scaling the y-coordinate with a factor of -1.
This is just for visualization!
In most situations, this is not required by non-maritime users. However, for ship hull designers, a symmetric ship hull can be quickly mirrored with this button, just to have a look at the entire ship hull (while modeling only one half of it).
The shortcut “F5” turns the mirroring on and off.
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