# Controlling brush diameter increment when using Shift+Scroll

**URL:** <https://discourse.slicer.org/t/controlling-brush-diameter-increment-when-using-shift-scroll/4247>\
**Category:** Support\
**Tags:** segmentation, python\
**Created:** [October 1, 2018, 4:31pm UTC](https://discourse.slicer.org/t/controlling-brush-diameter-increment-when-using-shift-scroll/4247 "2018-10-01T16:31:12Z")\
**Posts on this page:** 1\
**Showing post:** 10

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**Author:** ![lassoan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/lassoan/32/13_2.png) [@lassoan](https://discourse.slicer.org/u/lassoan)\
**Post date:** [October 2, 2018, 8:12pm UTC](https://discourse.slicer.org/t/controlling-brush-diameter-increment-when-using-shift-scroll/4247/10 "2018-10-02T20:12:28Z")

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Good. I guess not re-creating the segment editor widget fixed the selection reset issue.

Brush parameters are shared between paint and erase effects, so it is a common parameter, which need to be set by using `setCommonParameter` method:

```
effect.setCommonParameter("BrushDiameterIsRelative", "0")
effect.setCommonParameter("BrushAbsoluteDiameter", newDiam)
```

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