If you want a window you can adjust, you will need a purpose made object that will allow you to do what you want.
Try searching for 'polygonal window' in the window settings dialogue and download it.
Or if you want a one-off custom window then you can create it yourself.
https://helpcenter.graphisoft.com/knowledgebase/25564/
Barry.
One of the forum moderators.
Versions 6.5 to 27
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