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fixes#3973https://forum.freecadweb.org/viewtopic.php?p=316251#p316198
This commit disables an old "axis orientation correction mode", which tried to
solve a problem with orientation of the axis. It never worked fine and it should
have never been introduced, as everything it intends to do should be done by
setting the appropriate placement offset.
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fixes#3926
Points made of construction type are special non-constrainable points, such as (current) bspline knots.
This was not intended in Carbon Copy.
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fixes#3974
Snapping to 45 degrees during arc creation (hold ctrl during an arc within a polyline), resulted in
reduced precision, because Gui::Command::doCommand %f defaults only to six decimal positions, which is
a poor representation in radians of, for example, 90 degrees.
A work-around could have been to hardcode a higher number of decimals, as in %0.Xf. However, I do not like
such magic numbers.
The solution chosen is to use an App.Quantity object using as units degrees, which leads to no loss of precision.
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Selecting first the horizontal/vertical constraint and applying to a line segment with
a previous horizontal/vertical alignment constraint caused FreeCAD to refuse applying it.
fixes#4013
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In maximum verbose debug mode, information is given about the groups of Sketcher Constraints that the solver is considering for redundancy or conflict.
This is before the popularity contest selects the constraint shown in the solver messages.
The main reason for showing this is to enable to diagnose problems with sketches in which the constraint indicated as the redundant one appears not to
be the right one. Intended for power users with "iteration level" debug mode.
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Copy constructor made private, as copies are handled via copy() and clone() methods which generate pointers, not objects.
Private copy constructor, used for copy(), made default implementation.
Destructor made default.
Copy and Clone made non-virtual, as the class does not have children.
Added override to persistance inherited virtual functions.
move operators explicitly disallowed to note that they are not intended in the current implementation.
Perfectly ok to have only private copy constructor for internal use
