# Read data file from disk and convert displayable node to vtkActor or vtkProp

**URL:** <https://discourse.slicer.org/t/read-data-file-from-disk-and-convert-displayable-node-to-vtkactor-or-vtkprop/19244>\
**Category:** Support\
**Created:** [August 18, 2021, 9:16am UTC](https://discourse.slicer.org/t/read-data-file-from-disk-and-convert-displayable-node-to-vtkactor-or-vtkprop/19244 "2021-08-18T09:16:38Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![xianger-qi](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/xianger-qi/32/11944_2.png) [@xianger-qi](https://discourse.slicer.org/u/xianger-qi)\
**Post date:** [August 18, 2021, 9:16am UTC](https://discourse.slicer.org/t/read-data-file-from-disk-and-convert-displayable-node-to-vtkactor-or-vtkprop/19244/1 "2021-08-18T09:16:38Z")

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I have some Non-DICOM data files. such as \*.nrrd, \*.stl, etc. but how can i read these data files from disk in C++, and convert these to vtkActor or vtkProp class? Thanks for replying!

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**Author:** ![xianger-qi](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/xianger-qi/32/11944_2.png) [@xianger-qi](https://discourse.slicer.org/u/xianger-qi)\
**Post date:** [August 19, 2021, 8:49am UTC](https://discourse.slicer.org/t/read-data-file-from-disk-and-convert-displayable-node-to-vtkactor-or-vtkprop/19244/2 "2021-08-19T08:49:38Z")

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Another question is how can i convert slicer data node to vtkProp or vtkActor and so on, because, maybe i want to display the data node via vtk render window directly not via slicer scene.

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**Author:** ![pieper](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/pieper/32/8_2.png) [@pieper](https://discourse.slicer.org/u/pieper)\
**Post date:** [August 19, 2021, 10:48am UTC](https://discourse.slicer.org/t/read-data-file-from-disk-and-convert-displayable-node-to-vtkactor-or-vtkprop/19244/3 "2021-08-19T10:48:35Z")

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In Slicer the mapping between mrml nodes (for image and poly data) and vtk rendering is handled by displayable managers:

[https://www.slicer.org/wiki/Documentation/Nightly/Developers/DisplayableManagers](https://www.slicer.org/wiki/Documentation/Nightly/Developers/DisplayableManagers)