# BackingStore not updated after removing vtkProp

**URL:** https://discourse.vtk.org/t/backingstore-not-updated-after-removing-vtkprop/16366
**Category:** Development
**Created:** [March 31, 2026, 8:51pm UTC](https://discourse.vtk.org/t/backingstore-not-updated-after-removing-vtkprop/16366 "2026-03-31T20:51:15Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![mholladay](https://discourse.vtk.org/user_avatar/discourse.vtk.org/mholladay/32/10591_2.png) [@mholladay](https://discourse.vtk.org/u/mholladay)
#### Post date: [March 31, 2026, 8:51pm UTC](https://discourse.vtk.org/t/backingstore-not-updated-after-removing-vtkprop/16366/1 "2026-03-31T20:51:15Z")

</div>

When using a vtkRenderer with BackingStoreOn(), the display does not seem to get updated when a vtkProp is removed from the scene or when its visibility transitions from 1 to 0. It looks like this is probably caused by the way vtkRenderer::Render loops over the visible props when checking for changes – that loop won’t detect when something changes from visible to invisibile or when something has been removed from the collection of props.

To work around this, I have to explicitly mark the renderer, camera, or renderwindow as Modified() after removing the prop.

Is this behavior by design? Should the renderer instead be automatically marked as Modified when a prop is removed or changes from visibile to invisible?