# Axis constraint on vtkFinitePlaneWidget

**URL:** https://discourse.vtk.org/t/axis-constraint-on-vtkfiniteplanewidget/13759
**Category:** Development
**Created:** [April 20, 2024, 4:22pm UTC](https://discourse.vtk.org/t/axis-constraint-on-vtkfiniteplanewidget/13759 "2024-04-20T16:22:15Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![Jens\_Munk\_Hansen](https://discourse.vtk.org/user_avatar/discourse.vtk.org/jens_munk_hansen/32/1215_2.png) [@Jens\_Munk\_Hansen](https://discourse.vtk.org/u/Jens_Munk_Hansen)
#### Post date: [April 20, 2024, 4:22pm UTC](https://discourse.vtk.org/t/axis-constraint-on-vtkfiniteplanewidget/13759/1 "2024-04-20T16:22:15Z")

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Hi Developers

The `vtkFinitePlaneWidget` works great, but I do miss a small feature that can be easily added.

Currently the plane can be pushed along the axis and the two points can be moved freely to create a Parallelogram. It is trivial to add a small option that will enforce the plane to be rectangular, e.g. a `vtkBool` named `RectangularShape`.

The widget is a little nasty in the sense that there is no abstract interface for its representation, so changing this outside `VTK` is a clone and own. I do think though that this small addition will be of use.

 ![Screenshot from 2024-04-20 18-14-18](https://discourse.vtk.org/uploads/default/original/2X/c/c2fb4b2917d7cc54440b0feaed97a8f3b6723583.png)

When `RectangularShape` is on, moving the two points will simply change the width and height of the widget instead of creating a parallelogram.

I will make a small pull request.