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https://forum.freecadweb.org/viewtopic.php?p=387303#p387303
1. Trim had a bug that the type of the constraint on the second point was equal to the first one regardless of the situation.
2. Trim did not have support for checking whether points were close to the edge and relied on preexisting constraints.
PropertyExpressionEngine is changed to derived from a new class
PropertyExpressionContainer, which is in turn derives from
PropertyXLinkContainer. This makes PropertyExpressionEngine a link type
property that is capable of external linking. It now uses the unified
link property APIs for dependency management and tracking of object
life time, re-labeling, etc.
ObjectIdentifier is modified to support sub-object reference, but is
not exposed to end-user, because expression syntax is kept mostly
unchanged, which will be submitted in future PR. There is, however,
one small change in expression syntax (ExpressionParser.y) to introduce
local property reference to avoid ambiguity mentioned in
FreeCAD/FreeCAD#1619
Modified Expression/ExpressionModifier interface to support various link
property API for link modification.
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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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Trimming was not considering a case where an ellipse is trimmed with respect to its own internal aligment geometry.
This resulted in Coincident Constraints with PointPos = Sketcher::none, which is invalid.
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Intercurve fillet uses endpoint constraints for improved accuracy, but before this
commit was only considering a coincident constraint. Now it also considers an endpoint
tangency or perpendicular.
delConstraintOnPoint with coincidentonly=false, was not checking endpoint perpendiculars and
would therefore fail to delete them.
https://forum.freecadweb.org/viewtopic.php?f=3&t=31594&start=30#p265731
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This commit introduces two functions to operate on all datum constraints exclusively:
- Make all datum constraints driving or not driving, depending on the argument.
- Move all datum constraints at the end of the constraint list.
The practical use an ongoing effort towards improving the block constraint behaviour, that will be defered to 0.19
