# GetPlaneCornerPoints function and vtkPoints Class

**URL:** <https://discourse.slicer.org/t/getplanecornerpoints-function-and-vtkpoints-class/37125>\
**Category:** Support\
**Tags:** python\
**Created:** [July 1, 2024, 5:55pm UTC](https://discourse.slicer.org/t/getplanecornerpoints-function-and-vtkpoints-class/37125 "2024-07-01T17:55:28Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![ahenry](https://avatars.discourse-cdn.com/v4/letter/a/3da27b/32.png) [@ahenry](https://discourse.slicer.org/u/ahenry)\
**Post date:** [July 1, 2024, 5:55pm UTC](https://discourse.slicer.org/t/getplanecornerpoints-function-and-vtkpoints-class/37125/1 "2024-07-01T17:55:28Z")

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Hello,

I am interested in calling the RAS coordinates of the corners of markup planes after they have been created and rotated. I checked the api docs and found that the vtkMRMLMarkupsPlaneNode class has a GetPlaneCornerPoints function that takes in a vtkPoints object, but I did not see anything in the docs about the vtkPoints object. Is there a way I can get the plane corner points easily and is there any other info on the vtkPoints object?

Thanks,

---

<div class="post-metadata">

**Author:** ![ahenry](https://avatars.discourse-cdn.com/v4/letter/a/3da27b/32.png) [@ahenry](https://discourse.slicer.org/u/ahenry)\
**Post date:** [July 3, 2024, 6:37pm UTC](https://discourse.slicer.org/t/getplanecornerpoints-function-and-vtkpoints-class/37125/2 "2024-07-03T18:37:02Z")

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I was able to find a solution. I found the vtkPoints class in the vtk api documentation. Here is how I solved my issue.

```auto
from vtkmodules.util.numpy_support import vtk_to_numpy

#create instance of plane markup class
plane = getNode('Name_of_Plane_Markup')

#create instance of vtkPoints
points = vtk.vtkPoints()

plane.GetPlaneCornerPoints(points)

corner_points = vtk_to_numpy(points.GetData())

```