Sketcher: constrângere de simetrie
Sketcher ConstrainSymmetric |
Menu location |
---|
Sketch → Sketcher constraints → Constrain symmetrical |
Workbenches |
Sketcher |
Default shortcut |
S |
Introduced in version |
- |
See also |
Constraint Parallel |
Description
Descriere
Constrângerea de simetrie obligă două puncte selectate pentru a deveni simetrice cu o anumită linie de simetrie, adică două puncte selectate sunt constrânse să stea pe o linie normală care trece prin cele două puncte și sunt constrânse să fie echidistan0te față de linia de simetrie. Alternativ, poate forța două puncte să fie simetrice față de al treilea.
Utilizare
Selectați două puncte (vârfuri) din schiță și o linie din schiță. Punctele selectate și linia vor fi verde închis.
Click pe iconița SymmetricalConstraint în bara de instrumente Sketcher sau selectați elementul de meniu Constrain Symmetrical din submeniul Sketcher Costraint din elementul de meniu Sketcher (sau Part Design).
Aceasta va aplica constrângerea elementelor selectate.
Aceasta este o constrângere geometrică și nu are parametri editabili.
Select two points (vertexes) in the sketch and a line in the sketch. The selected points and the line will be dark green.
Click on Constrain symmetric or select the Constrain Symmetrical menu item from the Sketcher Constraints sub menu of the Sketcher (or Part Design) menu item.
This will apply the constraint to the selected items.
Note: Before Version 0.19 (see fix [1]), if you want to define a symmetry constraint with respect to a point, the order of the selection is important, depending on if you select the tool at the beginning or at the end.
- If you click the tool first: select the first point, then the symmetry reference point, and finally the second point.
- If you click the tool last: select the first point, then the second point, and finally the symmetry reference point.
See the tracker issue #4144, and forum thread.
Scripting
Two points and a symmetry line:
Sketch.addConstraint(Sketcher.Constraint('Symmetric', Line1, PointOfLine1, Line2, PointOfLine2, SymmetryLine))
Two points and a symmetry point:
Sketch.addConstraint(Sketcher.Constraint('Symmetric', Line1, PointOfLine1, Line2, PointOfLine2, LineS, PointOfLineS))
A line and a symmetry point (In the GUI one can select a line and a point, but it uses internally the same form as above, with the two extremities of the same line):
Sketch.addConstraint(Sketcher.Constraint('Symmetric', Line, 1, Line, 2, LineS, PointOfLineS))
The Sketcher scripting page explains the values which can be used for Line1
, Line2
, LineS
, Line
, PointOfLine1
, PointOfLine2
and PointOfLineS
, and contains further examples on how to create constraints from Python scripts.
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