# Is there a way to track pan and zoom events from certain mouseManipulators?

**URL:** https://discourse.vtk.org/t/is-there-a-way-to-track-pan-and-zoom-events-from-certain-mousemanipulators/11513
**Category:** Support
**Created:** [May 22, 2023, 3:53pm UTC](https://discourse.vtk.org/t/is-there-a-way-to-track-pan-and-zoom-events-from-certain-mousemanipulators/11513 "2023-05-22T15:53:13Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![DavidO](https://discourse.vtk.org/user_avatar/discourse.vtk.org/davido/32/7120_2.png) [@DavidO](https://discourse.vtk.org/u/DavidO)
#### Post date: [May 22, 2023, 3:53pm UTC](https://discourse.vtk.org/t/is-there-a-way-to-track-pan-and-zoom-events-from-certain-mousemanipulators/11513/1 "2023-05-22T15:53:13Z")

</div>

Hi there,

I’d like to track the user interactions of pan and zooming events that are enabled by the following manipulators:

vtkMouseCameraTrackballPanManipulator  
vtkMouseCameraTrackballZoomToMouseManipulator

Does VTK expose anything related to this? At the moment I’m having to track events such as `onMouseWheel`, `onLeftButtonPress` and `onLeftButtonRelease` to manually compute these values, in terms of the zoom level (getParallelScale) and the drag events, when I imagine VTK is already doing this work.

I’m a little bit lost in the docs, but not completely certain i’ve not missed anything.

Many thanks!

David