# Picking label points

**URL:** https://discourse.vtk.org/t/picking-label-points/11401
**Category:** Support
**Created:** [May 7, 2023, 9:41pm UTC](https://discourse.vtk.org/t/picking-label-points/11401 "2023-05-07T21:41:22Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![machur](https://discourse.vtk.org/user_avatar/discourse.vtk.org/machur/32/7049_2.png) [@machur](https://discourse.vtk.org/u/machur)
#### Post date: [May 7, 2023, 9:41pm UTC](https://discourse.vtk.org/t/picking-label-points/11401/1 "2023-05-07T21:41:22Z")

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Hi,

I’m using VTK to visualize medical data in Python. My goal is to display 3D points with “clickable” labels, so I can pick a label and hide it from the user.

I found the following example in C++ that pretty much covers the Python implementation that I’ve been using: [https://kitware.github.io/vtk-examples/site/Cxx/Visualization/LabelPlacementMapper/](https://kitware.github.io/vtk-examples/site/Cxx/Visualization/LabelPlacementMapper/)

I’m a newbie to VTK and I’m wondering where is stored the information about the shapes and positions of the 2D objects representing labels on the screen? Is it possible to get a list of bounding boxes in 2D pixel space somehow? I’ve seen that there is a lot of code to calculate overlaps etc, but I don’t see API to return any specific values for all labels.

Ideally, I would like to click on a label (box with description, not the point) and check whether 2D coordinates from mouse click are within label bounds to get the corresponding point/actor.