Archicad doesn't like the model to be too far from the origin - but I wouldn't say 500m is very far at all.
Usually you start to see glitches in the 3D - not that it just disappears.
I am wondering if you maybe have a 3D cutting plane.
You can turn of the cutting planes or delete them completely.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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