The latter is intended for a specific solver constraint.
[Sketcher] Make further changes for tangent-at-knot separation
1. Remove code for tangent-at-knot from `addAngleAtPointConstraint`.
2. Use correct order of input.
3. Separate internal C0 knot vs end knots. The latter can still be constrained
but the user must use endpoints of the spline instead of knots.
Similar to 2715a66ff02a46f94ae3fc6527fd446e666b8e58.
Added some comments and removed some TODO's.
Return grad values directly rather than doing summation.
Also squashes:
[Sketcher] Make tangent-at-knot with just knot and line
[Sketcher] Disallow tangent at C0 knot
If passed on to planegcs can cause segmentation fault.
[Sketcher] (Re-)Support tangent at B-spline end-knots
New code had introduced problems for non-periodic spline end-points, and
periodic spline "end-points" were not supported anyway.
(here end-points mean star/end points)
- calling GetInt several times makes problems - on some PCs there is no orbit selected, on some always the same
- furthermore the action order matters
- also remove an unnecessary function call
It is possible to ask for splitting at an end point of the curve. This leads to
a `CADKernelError` and leaves us with a "hanging" clone. This check prevents that.
===================================
Changes from naked pointers to smart pointers are motivated to the use of functions that can reasonably throw under certain circumnstances (such as trim).
When introducing smart pointers, it is not necessary to explicitly delete the new geometry array at the end of the function.
When using the new facility to add a smart pointer geometry (previous commit), the copies generated in the split algorithm can be reused, which renders
keeping track of the new geometry for memory management unnecessary.
As geometry is added to the property which each call to addGeometry, the stored newIds can be reused if access is necessary to geometry pointers afterwards
(e.g. for constraint management).
================================================================
This new facility avoids to have to create a new copy() when a user copy is already created.
As the user copy is reused via move semantics, memory management is simplified.
CAVEAT: When this facility is used, the client code has to ensure whether a copy() or a clone() of the Part::Geometry
should be undertaken. The different between both is that the former creates a new uuid (tag), whereas the latter does not.
When `v == u` we want to "break" the b-spline at `u` (also OCC will raise an
exception if same parameter is provided).
The range of parameter can in general be different than 1.0, so use a general term.
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A migrated parabola cannot be openned with a previous version of FreeCAD. The user is notified upfront.
