Understanding .GEM file errors

Hi @mostapha

Whats the best way to track the errors that are shown when we import the .gem file?

In the example, below and other ones that I faced couple of times, when I import the model to RH, it either shows a long list of errors, but opens the model often, but in few times it even couldnt open the model like the one below:

It doesnt basically mention which zone/surface is talking about, and I need more information to understand the problem.

I ll send you the .gem file through DM.

But my main question is, how we should deal with such errors coming from the incompatibility between IES and RH?


Hi, @amirtabadkani - thank you for sharing your model.

Without seeing the models it is hard to tell but there are two common cases that can cause issues during the translation from GEM to HBJSON. And both are fairly easy to fix.

  1. Adjacency errors: GEM file doesn’t include the adjacency information. As a result, and when it is converted to HBJSON, all the faces get assigned a default boundary condition based on the face type (Outdoors or Ground). This is fine in most cases but if you have voids in the IES model it can become a problem. The reason is that voids are translated to AirBoundary and AirBoundary should always be adjacent to another AirBoundary face. You can resolve this issue by simply run the solve adjacency command after importing the model.

  2. Tolerance errors: In some cases the models from IES are not fully closed. In most cases, Pollination resolves these tolerance issues during the import process. If a room is missing a face, you can use the cap command to fix it.

The error that you see below is because there is a face in your model that has a Z value smaller then 0 and also has an aperture. Pollination defines the boundary condition as Ground because of the negative Z value, and then it raises an error when tries to add an aperture because it is not technically possible for a face with Ground boundary condition to have an aperture. That’s why you get the error. If the GEM file had the boundary condition, it could have been avoided.

This is one of the two rooms that are source of the problem:

There are two improvements on our end to help with this issue:

  1. Make the GEM → HBJSON more flexible to avoid such cases by changing the boundary condition to Outdoors and assign the aperture. I already pushed a fix for this, and it should be available in the next release of the Rhino plugin. Here is the report from your model.

    Changing boundary condition from Ground to Outdoors for 4180eae7-9c34-4c58-8736-54dc9ed1263b in Lifts [Lifts_bfc084b5].
    Changing boundary condition from Ground to Outdoors for 700cd544-4a4a-4d8b-ba62-500f59c1e62e in GF-Lobby-Corridors [GF-Lobby-Corridors_065bd881]
  2. Improve the error message to provide the name of the room, and face. This is something that @chriswmackey can comment on.

I shared the 3dm model with you in the private message so you can carry on with your project.

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Thanks @amirtabadkani .

I improved the error message to include the name and ID of the face that is causing issues:

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Thanks, Mostapha

Yes, I understand this should be the issue…

But this is what I am looking for to just identify the rooms/surfaces to fix it in IES… it might be very easy for you to identify because you developed the program but for me as a typical user, I need more information for all types of potential errors as to be able to debug…

Thanks @chriswmackey for your prompt action …

2 posts were split to a new topic: How to fix the non-watertight rooms?