topic Re: Room adjacency + CalculateSpatialElementGeometry in Revit API Forum

Room adjacency + CalculateSpatialElementGeometry

Anonymous — Wed, 13 Nov 2013 14:41:53 GMT

Hi all,

I'm using the class CalculateSpatialElementGeometry to determine room/space adjacency in a Revit MEP project.

I want to know each boundary of a given room/space (wall, ceiling, floor).

My code is almost the same as the one used in this Wiki

Here is a part of my source code :

SpatialElementBoundaryOptions Opt = new SpatialElementBoundaryOptions();
Opt.StoreFreeBoundaryFaces = false;
Opt.SpatialElementBoundaryLocation = SpatialElementBoundaryLocation.Finish;
Calc = new SpatialElementGeometryCalculator(doc, Opt);

SpatialElementGeometryResults G = Calc.CalculateSpatialElementGeometry(space);

Solid S = G.GetGeometry();

space is of class Space, but the problem is the same with a Room.

Problem : inside certain projects, it appears that the result of that code is not consistent through consecutive calls.

First call :

S.SurfaceArea = 162

S.Volume = 120

Second and subsequent calls :

S.SurfaceArea = 200

S.Volume = 250

Inconsistency can also be seen inside GetBoundaryFaceInfo, because SpatialElementBoundarySubface.SpatialBoundaryElement changes between calls 1 and 2+.

Of course, there is no modification to project database between calls.

Is it a known limitation of Revit API, or do I make something wrong ?

Many thanks in advance 😉

Re: Room adjacency + CalculateSpatialElementGeometry

mikako_harada — Fri, 22 Nov 2013 23:33:53 GMT

Hi Olivier,

would you like to attach a ready to build project for us to take a look?

Re: Room adjacency + CalculateSpatialElementGeometry

mikako_harada — Fri, 22 Nov 2013 23:35:08 GMT

and a minimum rvt file that we can run with.

Re: Room adjacency + CalculateSpatialElementGeometry

Anonymous — Mon, 25 Nov 2013 07:17:02 GMT

Hi Mikako.Harada,

I've solved the problem.

My calculation process was embedded in a transaction, and inside that transaction I was :

- Changing AreaVolumeSettings.GetAreaVolumeSettings(doc).ComputeVolumes value.

- Using SpatialElementGeometryCalculator to compute adjacencies.

That was the source of the inconsistency.

By isolating the modification to ComputeVolumes inside its own transaction, inconsistency has gone.

By the way, thanks you for your interest 😉

Re: Room adjacency + CalculateSpatialElementGeometry

mikako_harada — Tue, 26 Nov 2013 08:28:14 GMT

Excellent! I'm glad. Thank you for letting us know.