Sketcher ConstrainSymmetric
Sketcher ConstrainSymmetric |
Menu location |
---|
Sketch → Sketcher constraints → Constrain symmetrical |
Workbenches |
Sketcher |
Default shortcut |
S |
Introduced in version |
- |
See also |
Sketcher Constraint Parallel |
Description
The Sketcher ConstrainSymmetric command defines two selected points to be symmetrical around a given line, i.e., both selected points are constrained to lie on a normal to the line through both points and are constrained to be equidistant from the line. Alternatively it can constrain two points to be symmetric with respect to a third one.
Usage
Select two points (vertexes) in the sketch and a line in the sketch. The selected points and the line will be dark green.
There are several ways to invoke the command:
- Press the Constrain symmetric button.
- Select the Sketch → Sketcher constraints → Constrain symmetric option from the menu.
- introduced in version 0.22: Right-click in the 3D view and select the Constrain symmetric option from the context menu.
- Use the keyboard shortcut: S.
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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