# 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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