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In an introductory course for QGIS I stumbled over the following question: Is there a tool to easily move (/move&copy / rotate / simplyfy) only one part of a multipart feature? All tools edit the whole multipart polygon, only the "offset curve" tool works on parts (here the question is how to use "offset curve" on all parts of a multipart simultaneously). The behaviour seems to be the same for multipoint, multiline and multipolygon features.

I tried the common shortcut keys (Ctrl, Shift, Alt, AltGr, Tab, right click) but nothing worked. I couldn't find anything on Stackexchange or the rest of the web either. I know there is the solution to select the vertices and move them via the vertext tool, however this is not always a practical / fast way to do this.

This is a purely academical question as I do not have a specific project I need to use this on - it just struck me as odd.

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  • Aside from the solutions below, if you want to use common shortcut keys and they aren't working, you can set them by going to settings --> keyboard shortcuts. Just be careful what you choose.
    – Binx
    Commented Mar 17, 2022 at 14:32

3 Answers 3

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All that tools work on selected features, you can't select a part of a multipart feature separately, so you can't use them on a part.

If you need to do it the way is: separate the parts into different objects, work on the parts and join them again if you need/want.

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  • I know that there are workarounds. The course is mainly for civil administration workers who are not regular GIS users, however, so a simpler tool would have been nice to have - escpecially for something seemingly so simple. (Also, as mentioned the "offset curve" tool does only work on a part.) (and, to be precise: you don't even have to select the features to use those tools on them, you only have to enable editing on the layer...)
    – Hjall
    Commented Mar 17, 2022 at 13:08
  • I know, but's not the matter here... you can "select" one or more features and use a tool with all them, or with any feature "selected" use a tool on only one by clicking on it... that it's like select only that one just in the moment to work with it. Change the word selected for chosen if you prefer it.
    – JLR
    Commented Mar 17, 2022 at 14:06
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OpenJUMP can mostly do what you want.

Have a multipolygon

enter image description here

Select a part

enter image description here

Move/Scale/Rotate tools work on the selected part(s)

enter image description here

Usage of Move

enter image description here

OpenJUMP is open source. Ask QGIS developers if they would like to port the tool into QGIS.

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The solution is indeed the vertex tool : you just need to select all the vertices you want to move together. (so for you all the vertices of the part you want to move)

To select several vertices either click and drag (to select by rectangle) or hold MAJ and click on each vertices you want to select. Selected vertices should get a blue circle.

After selecting the vertices click on any selected vertices with the vertex tool and move it, all other selected vertices will move the same way.

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    It's a solution only when you want to move them, but not when you want to use another tool.
    – JLR
    Commented Mar 17, 2022 at 14:10
  • @JLR yes it only work for moving, for other tool the solution would be to use the Split (and after merge) feature tool and if you have a lot of part this is not optimal
    – J.R
    Commented Mar 17, 2022 at 14:24
  • sorry, i didn't read your answer, i take off mine.
    – pigreco
    Commented Mar 17, 2022 at 14:30
  • @pigreco NO your was better with the animation
    – J.R
    Commented Mar 17, 2022 at 14:39

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