DF - Context taken into account?

Hi @chris,
Want to ask regarding the use of context in DF.
I have a suspicionn that the model converted to HB doesn’t get this context.
I’ve assigned geometry to the DF_ContextShade component and connected it to the DF_Model (red surfaces in image below):

But then, after making the DF model a HB model the VizByType is not showing this context. I expected to have it on the outdoor_shades output, but it is not there.
Checked the idf file and i don’t see the context’s geometry, though i see window shades.

Am i right or there is something i’m doing wrong?

Hey @AbrahamYezioro ,

Your screenshot gives me all I need to know. The reason why you don’t get any context shade in your Honeybee Models is that you set the shade_dist_ to be 0:

This means that only shades with a distance of 0 from your building will be included in the exported Honeybee Models. If you disconnect this 0, you should get all of the shade written into the Honeybee Models and, if you connect a number other than 0, this will filter the context shades to only include the ones closest to your buildings. This feature is particularly useful when you have a Dragonfly Model with several buildings, representing an Urban district. You can export each building to it’s own Honeybee Model (for parallel simulation) and use the shade_dist_ to only include context shade that’s closest to each building like so:


I KNEW there should be a good reason i didn’t succeed. What a dumb.
Now is fine, and glad it was a mistake on my side.
I can comment you that i’m working on a component that knows how to filter the context surfaces that have the most potential to affect the energy simulation. Once the paper is written and accepted i’ll let you know. Maybe you’ll like to include it in the suit. From the image above you cansee that the context is much larger than the selected surfaces.
Thanks @chris,

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It’s all good. I would definitely be interested in reading your paper. Right now, the shd_dist_ input just does an analysis of the bounding rectangles around each building and piece of context shade in the XY plane. If the rectangles of the model and shade overlap within the shade distance, then the shade gets included in the model. Your method looks a lot more sophisticated and could probably cut down the simulation time for these large urban models.

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Good afternoon, I found this post very interesting, and I would like to know how you dealt with the shadows to keep only the most relevant ones @AbrahamYezioro . In my case, I would like to remove the shadows from the neighboring buildings in contact with the studio building on adiabatic walls, only those with the same height as the studio building, as these shadows will have little impact on the solution but a significant impact on the calculation time. I’m not sure if it would be possible to perform this shadow filtering quickly. Have I missed any other post or update @chris ? Thank you so much.

Thank you very much.

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@Batiste , we are in the process of re-factoring what we had 3 years ago. The paper is not yet published, but i’m optimistic we will soon. The algorithm is robust and we just need to finish the writing … and of course, get the paper accepted for publication. Crossing fingers on all that.