There are a lot of posts about this.
Just do a search for 'shadow AND plan' - I find searching in the ArchicadWiki link at the top of this forum is better than searching just in this forum.
i.e. here is one link to many others ...
http://archicad-talk.graphisoft.com/viewtopic.php?p=187290
Barry.
One of the forum moderators.
Versions 6.5 to 27
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