# VTK vtkSliderRepresentation2D to : scrollbar height changes when resizing window width only (using Display coordinates)

**URL:** https://discourse.vtk.org/t/vtk-vtksliderrepresentation2d-to-scrollbar-height-changes-when-resizing-window-width-only-using-display-coordinates/16210
**Category:** Support
**Tags:** code
**Created:** [January 6, 2026, 10:00am UTC](https://discourse.vtk.org/t/vtk-vtksliderrepresentation2d-to-scrollbar-height-changes-when-resizing-window-width-only-using-display-coordinates/16210 "2026-01-06T10:00:09Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![marlon.ma](https://discourse.vtk.org/user_avatar/discourse.vtk.org/marlon.ma/32/6091_2.png) [@marlon.ma](https://discourse.vtk.org/u/marlon.ma)
#### Post date: [January 6, 2026, 10:00am UTC](https://discourse.vtk.org/t/vtk-vtksliderrepresentation2d-to-scrollbar-height-changes-when-resizing-window-width-only-using-display-coordinates/16210/1 "2026-01-06T10:00:09Z")

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## Description

I am using vtkSliderWidget with vtkSliderRepresentation2Dto implement a **vertical scrollbar** for a thumbnail strip view.

My goal is:

- Pixel-precise control of scrollbar geometry

- Scrollbar **height should remain visually constant when resizing window width**

- Only x-position / thickness should respond to width changes

However, I observe the following issue:

> **Even after switching Point1 / Point2 to `Display` coordinates, resizing the window width still changes the scrollbar’s visual height.**

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### Author: ![Paulo\_Carvalho](https://discourse.vtk.org/user_avatar/discourse.vtk.org/paulo_carvalho/32/370_2.png) [@Paulo\_Carvalho](https://discourse.vtk.org/u/Paulo_Carvalho)
#### Post date: [January 7, 2026, 2:04pm UTC](https://discourse.vtk.org/t/vtk-vtksliderrepresentation2d-to-scrollbar-height-changes-when-resizing-window-width-only-using-display-coordinates/16210/2 "2026-01-07T14:04:33Z")

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Hello,

Indeed the display coordinate system is supposed to be in raw screen pixels (`(0,0)` being bottom-left), thus not to change with model zooming, window resizing, etc.. So, I guess we need to take a look at the part of the code involved.

best,

PC