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When writting solver implementations it has to be taken into account that the normal is not to be provided in the sense of the curvature, but to
the left when walking a curve from start to end.
https://forum.freecadweb.org/viewtopic.php?f=10&t=26312#p209486
This commit has impact on all the previous files using bspline and endpoint to endpoint tangency.
A work-around is to delete the tangency and do it again.
resolves#2683
Adds Refine property to sketch-based and transformation features. The
property is initialized according to preferences, and can be altered in
property editor on per-feature basis.
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fixes#2275https://freecadweb.org/tracker/view.php?id=2275
Deletion of coincidents rely on selected vertex. The original code was trying to delete a coincident without checking whether one was there.
The implementation now relies on checking whether a coincident is present.
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Users generally expect that validate Sketch checks the visible part, perhaps because it is not called from the sketcher's edit view, but from the 3D view, perhaps
because that part is relevant for further construction.
On the other hand the tool's name is Validate Sketch and construction geometry belongs to the sketch.
So a new checkbox is introduced, by default enabled to ignore construction, but still allowing the user to make it operate in one direction or the other.
See:
https://forum.freecadweb.org/viewtopic.php?f=3&t=26139&p=208582#p208693
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The sketch validation tool offers the functionality to detect missing coincidences. It is a problem that internal geometry causes detected missing coincidences.
Additionally, the tool only shows the visible profile and not the construction geometry.
This commit introduces the ignoring of construction geometry, which "fixes" the two behaviours indicated above.
fixes#3298
