Questions about the creation of room geometries with LBT 1.0

Hallo dear community,

I have some questions, about the creation of room geometries, with the new version of LBT 1.0.

  • I noticed, if the direction of the ceiling´s surface, look into the room (as it should be), the “GridRooms” component, create 2 sensor grid, one for the floor and one for the ceiling.

  • With the “GridRooms” component, I don´t have the possibility to remove a strip of xx cm along the walls of the room, which must not be taken in consideration.
    I could solve by replace the “GridRooms” with the “LB_GeneratePointGrid” component and set only the geometry to analyze, but the “RunRecipe” give me the following error: The model has the following duplicated sensor grid displays_name.

  • If I want to simulate simultaneously more rooms, by building it through the “RoomSolid” component, (avoiding to divide each room´s faces for each different rooms like with the “HBRoom”), is possible to recognize the diffuse reflectance of the material for the floor/wall/ceiling, since the component only detects a closed volume?

I attached a example script:
LBT-DaylightFactor_Forum.gh (84.9 KB)

Thanks in advance for those who can take away some doubts for the new workflow to follow.
Greetings
Liam R.

Hi @LiamRuvio . I can answer your questions but, first, I need to clear up a misconception:

This is not correct. All faces that form a Room should always point outwards from the room volume and this is needed for a whole host of reasons, from correct Room volume calculations to correct (future) 3-Phase calculations where the BSDFs need to face the right direction, etc. However, you do not need to worry about this since Honeybee automatically corrects the directions that the faces are pointing by analyzing the room solid (similar to how Rhino ensures all closed Breps have surfaces pointing outwards). You can use the “HB Visualize Normals” component to see that this is always the case.

Now to answer your questions:

  • You get points being generated for the ceiling because Honeybee automatically assigns the face type (floor, wall, roof) based on the normal direction of the surface. So, if you don’t provide the face type when you create the faces, it will be assigned a floor face type if it is pointing downwards. Looking at you model, I can see that you have a floor where there should probably be a ceiling:
  • You found a bug! You are right that you should use the “LB Generate Point Grid” component and the “HB Sensor Grid” for your purpose. @mostapha insisted that we use the display name to identify the sensor grids instead of the identifier a month or two ago and I forgot to change this component to treat the name like an ID. You can always get it to work on your end by setting the _name_ input for the component. But I just pushed a fix:
    https://github.com/ladybug-tools/honeybee-grasshopper-radiance/pull/54
    And here is your fixed sample file:
    LBT-DaylightFactor_Forum_CWM.gh (86.9 KB)
  • You are might to have to further explain what you mean here. Are you asking how you can set up logic to automatically assign a certain modifier to all floors, walls, ceilings, apertures, of a Room? If so, you want to use ModifierSets. I’ll explain more if you can confirm this is what you want to do.

Dear @chris,
thank you for your kind and thorough reply.

About the first point, thank you for your very clear explanation, after so many years, I was not aware of this workflow, with the surface´s direction in Honeybee.
About the second point, I am happy that I helped you to discover this little “bug”, thanks that’s you fixed it, so fast!!
About the third point, my goal was to avoid dividing every surface (floor/wall/ceiling) for its belonging room, but to be able to group all the surfaces of all the rooms.
I realized only today, that I had the solution under my eyes. That is to group all the faces, openings and shades and connect directly to the “HBModel” component, without having to first build every single room.

Thank you for the beautiful new components and for all your work

Greetings
Liam R.

A post was split to a new topic: How to Set Up Radiance Models Without Rooms