subregion error

[andrewmc]

I have read many of the posts regarding subregions but haven't as yet found one that addresses this problem. When I try to create a subregion with even the most simple of shapes as a boundary, Revit cuts the subregion ok but then deletes all of the remainder of the toposurface. The model and base toposurface is quite large and this could be a cause as I have successfully created subregion in a very small file. Has anyone else had this problem??

I also have a similar problem regarding merge surfaces in the same large toposurface. When I try to merge a smaller surface which I have split, Revit deletes the entire toposurface.

Regards,

Andrew

[blads]

I have read many of the posts regarding subregions but haven't as yet found one that addresses this problem. When I try to create a subregion with even the most simple of shapes as a boundary, Revit cuts the subregion ok but then deletes all of the remainder of the toposurface. The model and base toposurface is quite large and this could be a cause as I have successfully created subregion in a very small file. Has anyone else had this problem??

I also have a similar problem regarding merge surfaces in the same large toposurface. When I try to merge a smaller surface which I have split, Revit deletes the entire toposurface.

Regards,

Andrew

With regards to split regions - there are two ways to sketch the split surface.

sketch a single closed loop that does not touch any of the boundaries of the surface, or
sketch any number of open loops. Remembering that both ends of an open loop must lie on the boundary of the surface, and no part of the open loop can intersect with the boundary of the surface.
With regards to merged regions - in order to merge two surfaces, they must share a common edge or overlap.

Hope that helps

[andrewmc]

Thanks blads,

I'm pretty sure I'm using the methods you suggested. The problems were occuring with a large and complex toposurface. I have split a part of the toposurface into a much smaller area and the subregion in it works fine.

Cheers,

Andrew

[sbrown]

check to see if your topo surface is a large distance from the origin, if so relocate it to the origin "tools>project position>relocate this project" then drag at 3000ft intervals until you get close to the origin. I couldn't edit a topo surface that was far from the origin. after relocating it things worked better.