Constraint Internal Alignment/es
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| Ubicación en el Menú |
|---|
| Sketch → Sketcher constraints → Constrain InternalAlignment |
| Entornos de trabajo |
| Sketcher |
| Atajo de teclado por defecto |
| Ctrl+A |
| Introducido en versión |
| - |
| Ver también |
| Show/Hide Internal Geometry, Ellipse |
Description
The InternalAlignment constraint aligns lines and points to particular places of a complex sketcher element (there is just one "complex" element so far, the Ellipse).
For 
Ellipse and 
Arc of ellipse, it supports constraining lines to become major and minor diameters, and constraining 
points to positions of ellipse's foci.
The constraint is for experienced users because its usage is not as straight forward as for the other constraints. There is a helper tool called 
Show/Hide internal geometry to avoid the need to invoke the InternalAlignment constraint manually.
Operation on Ellipse
- Select elements to be aligned and an ellipse. The ellipse must be selected last. Accepted are up to two lines and up to two points.
- Invoking the constraint can be done several ways:
- Pressing the
Constrain internal alignment button in the toolbar. - Using the Ctrl + A keyboard shortcut.
- Using the Sketch → Sketcher constraints → Constrain InternalAlignment entry from the top menu.
- Pressing the
The first line that was selected gets aligned to become ellipse's major diameter (but if it is not occupied already by another line, otherwise it will become minor diameter). The second line is aligned to become minor radius. The lines are automatically switched to construction.
Likewise, the first point is constrained to become the first unoccupied focus, and the second point goes to the other focus.
Note: By default new ellipses have an internal construction geometry. When this defines the ellipse already completely, you cannot directly use the InternalAlignment constraint. You first need to delete the construction geometry or parts of it. In case you don't see the construction geometry, select the ellipse and use the tool Show/Hide internal geometry to make it visible.
Scripting
Sketch.addConstraint(Sketcher.Constraint('InternalAlignment:EllipseMajorDiameter', index_of_line, index_of_ellipse))
Sketch.addConstraint(Sketcher.Constraint('InternalAlignment:EllipseMinorDiameter', index_of_line, index_of_ellipse))
Sketch.addConstraint(Sketcher.Constraint('InternalAlignment:EllipseFocus1', index_of_point, 1, index_of_ellipse))
Sketch.addConstraint(Sketcher.Constraint('InternalAlignment:EllipseFocus2', index_of_point, 1, index_of_ellipse))
Remarks:
Sketchis a sketch object.- Number
1in the focus calls stands for starting point of a point element (it is ignored). - The
index_of_pointargument must be a point, it cannot be used to e.g. denote an edge's extremity.
The Sketcher scripting page explains the values which can be used for index_of_line, index_of_point and index_of_ellipse and contains further examples on how to create constraints from Python scripts.
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