There is a very old post here with a "tentmaker" object.
https://archicad-talk.graphisoft.com/viewtopic.php?p=34271&sid=60f5113ac5263c2e02f4f07e260c8fd8#p342...
I did see a post in 2013 from Oliver Denton saying there was an updated object - but there is no longer any link in that post.
The old one should still work and once yo have the shape you can convert to a morph if need be (although that will be hard to edit further if you need to).
Maybe a bit of googling for "tentmaker" or "shade sail" might find some newer results.
Oliver hasn't been active here since 2014.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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