Error was thrown if FreeCADGui.Selection list had more than one item. Solution is to clear selection before adding selection from import operation. I also removed the `for` loop since the selection should be singular.
This fixes issue
https://tracker.freecadweb.org/view.php?id=4513
addSymmetric will now only transfer Vertical and Horizontal constraints if the reference axis is either
- the HAxis
- the VAxis
- a Vertical line
- a Horizontal line
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With the new solver ability to identify groups of dependent parameters, even with SparseQR, it is now possible to properly implement Blocked constraint (blocked geometry state/mode).
This comes at the cost of two consecutive diagnosis (4 QR decompositions, running in parallel by pairs, so the double of time than when not using any blocked constraint).
A first diagnosis identifies the groups of dependent solver parameters.
If any of these groups comprises a parameter affected by a blocked constraint, the parameter is fixed. As only one parameter from each group is fixed, there are no (partly) redundant parameters involved.
Then the new adapted system is solved.
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Do not copy/array internal alignment geometry if the geometry it defines is not part of the operation. Silently ignore it.
If the reference for the operation is one such geometry (or it is the only one), then abort the operation.
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Internal Alignment constraint mirroring was never implemented. With the enhancements
brought with implementation of geometry extensions in the sketcher, this lack of
implementation became a crash, as geometry was marked as being internal alignment, while
no associated internal alignment constraint was created.
Restrictions:
- Internal alignment geometry is only to be mirrored if the geometry it defines is also
being mirrored. Internal alignment geometry is otherwise skipped. This is because it
does not make sense to have a pole without a b-spline, or a major axis of a ellipse without
an ellipse.
fixes#4514