topic Re: Export of multiple GBXML models in Revit API Forum

Export of multiple GBXML models

Anonymous — Sun, 22 Mar 2020 10:31:03 GMT

Hello everyone!

For my Thesis work at my university I have to make a lot of different GBXML models (around 18000). No way I can do that without code.

This is what I came up with (I attached only a part of it; FloorR, WallsR, RoofR are lists to set R value of corresponding elements):

####### Setting Enegry Analysis parameters ############# opt=Analysis.EnergyAnalysisDetailModelOptions() opt.EnergyModelType=Analysis.EnergyModelType.BuildingElement opt.ExportMullions=False opt.IncludeShadingSurfaces=False opt.SimplifyCurtainSystems=True opt.Tier=Analysis.EnergyAnalysisDetailModelTier.SecondLevelBoundaries ##### loop over all R-value combinations and create models #################### t=Transaction(doc,"R change") c=Transaction(doc,"model creation") for i in range(len(FloorR)): for j in range(len(WallsR)): for k in range(len(RoofR)): t.Start() Floor.Set(FloorR[i]/0.3048) #R-value change for floor Wall.Set(WallsR[j]/0.3048)#R-value change for Walls Roof.Set(RoofR[k]/0.3048)#R-value change for roof t.Commit() t.Dispose() c.Start() model=Analysis.EnergyAnalysisDetailModel.Create(doc, opt) model.TransformModel() GBopt=GBXMLExportOptions() GBopt.ExportEnergyModelType=ExportEnergyModelType.BuildingElement doc.Export("C:\Users\Миша\Desktop\ASD","0"+","+str(0.2/FloorR[i])+","+str(0.3/WallsR[j])+","+str(0.3/RoofR[k]), GBopt) c.Commit()

This creates models, but I ran into a problem I dont fully understand: as the process continues, it slowes down and stops at about 170-175 created models. Apparently, comething is taking up the memory. I tried to doc.Delete(model) at the end of each 'for' loop, but it didnt help either.

What could be a solution?

Thank you !

Re: Export of multiple GBXML models

jeremytammik — Sun, 22 Mar 2020 14:09:57 GMT

The behaviour you describe is completely expected and as designed.

Revit is an end user product designed to be driven by a human being.

Human beings are not expected to sit down and create 18000 models in one sitting.

I suggest you implement an external executable that drives Revit using the code you shared above and monitors progress as you export results from the models you create.

Whenever Revit starts slowing down, take note of how far you got in processing, kill the process, restart Revit and continue from where you left off.

This is a common approach to programmatically drive processes in batch mode that were not designed for it.

You can also search The Building Coder for further hints on batch processing Revit documents:

https://www.google.com/search?q=batch+processing&as_sitesearch=thebuildingcoder.typepad.com

Alternatively, you could generate your 18000 models online using Forge and DA4R:

https://thebuildingcoder.typepad.com/blog/about-the-author.html#5.55

Good luck and have fun with your thesis!

Cheers,

Jeremy

Re: Export of multiple GBXML models

Anonymous — Sun, 22 Mar 2020 14:45:14 GMT

I'll try those out, thank you for your answer!

Re: Export of multiple GBXML models

RIPENG — Mon, 05 Jun 2023 13:46:54 GMT

Based on the code snippet provided, it appears that only R-values are manipulated and not the underlying model geometry. If that's the case, best to use Revit to export a single gbXML seed file. Then iterate over desired seed file parameters (like R-value) in an environment like Python which is excellent for large scale text operations.

Two utilities that would help with the route described above:

1. XmlNotepad (to build familiarity with gbXML structure and mechanization),

2. xgbxml (Python library for gbXML parsing and manipulation).

-Jake