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How do I get overhang/fins shading surface in unique shading group from context/ground shading objects?

asked 2018-09-03 14:07:34 -0500

bwelle's avatar

updated 2018-09-04 08:50:55 -0500

When importing a gbXML file, I have many different shading surfaces. Some are fins, overhangs, adjacent buildings and ground. All have unique shade surfaceIDs, and unique names. I want to try to get all the fins and overhangs assigned to "Building" shading group and Adjacent Buildings and Ground to "Site" shading group so I can assign constructions and cost objects only to the Building Shading. How can I do this? Attached is the gbXML file that I'm importing.

Attached are images of gbXML and here is the link to download:



Here is an image of what it looks like once imported to OS:


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answered 2018-09-03 15:59:15 -0500

First, I want to point out that shade surfaces assigned to the "Building" category will rotate with the entire building, i.e. you set the Building's North Axis input field to something other than zero. Shade surfaces assigned to "Site" category will NOT rotate with the entire building -- they stay fixed no matter what orientation you set in the North Axis input field.

If you still want to separate shade surfaces into "Building" vs. "Site", read on. From your Capture3.PNG, it looks like all 15 shade surfaces are assigned to the "Building" category. The gbXML file doesn't have a parameter to set the "Building" vs. "Site" category -- this is only an OpenStudio construct, and so must be altered in the OpenStudio input file ending in OSM. If you want the 6 adjacent and ground shade surfaces at the bottom of that Capture3.PNG to be assigned to the "Site" category instead, you'll need to make a new Shading Group in the OSM first, and then move the 6 shade surfaces from the existing Shading Group to the new Shading Group. This will be easier to do in the SketchUp plug-in for OpenStudio using cut / paste processes rather than in the OpenStudio application.

You can read more about shading in OpenStudio in other posts here and here.

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Great, thanks Aaron. We are are developing a fully automated process from gbMXL to OSM to OS server from a web GUI so there is not manual intervention. Looks like it would be best to do the post-processing of the OSM with a measure to reassign shading surfaces. Thanks!

bwelle's avatar bwelle  ( 2018-09-03 17:43:47 -0500 )edit

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Asked: 2018-09-03 14:07:34 -0500

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Last updated: Sep 03 '18