Closed Brep and Sunlight hours

Hi, I have to problems with the attached definition

  1. How do you input a geometry for the shadow study component in ladybug? I had a rhino geometry that I set as as reference brep, which I guess it doesn’t work. I looked at your sample file and your geometry was a close brep, if that the problem, how do you convert a rhino geometry into a close brep?

  1. In the sunlight hours component, I’m getting less than 1 hour of sun on a horizontal surface with no obstructions on June 22 at noon in Dallas, TX. Which is not possible, so I do not know what I’m doing wrong, and would appreciate your help very much.

Thank you, gh and 3dm files attached.

Solar Study_HZ_extruded.3dm (2.16 MB) (108 KB)

Hi Helena,

For your first point I think it has to do with the type of surfaces the component can accept. It seems to be similar to shade benefit evaluation, so only surfaces will do (i.e. no meshes or polysurfaces on the brep geometry). You seem to have one polysurface selected (the right side of your building). I changed that to a simple surface and it seems to work.

I’m attaching the files. By the way I changed the weather file and took away some of the inputs, you should revert to your settings.

Edit: By works I meant the error is not showing anymore. Not really sure it works as I haven’t used any of these components yet.

Hope this works.

Kind regards,

Theodore. (106 KB)
SolarStudy_HZ_extruded_surface.3dm (2.24 MB)


For point 2 i suggest to flip the normal direction of the ground surface. It should point upwards.


Theodore, Abraham, thank you for your responses. I still can’t get it to work.

For point 1, you were right Theodore, it was the type of surface, the shade component doesn’t give me an error anymore, but it doesn’t give me a result either. I’m also a little confused because in the file you attached to your response the brep geometry that is working is seems to be a curve, not a surface.

For point 2, I checked the surface normals and the surface is pointing upwards. I also try flipping the surface, and the result was no sun hours at all, so I deleted it, made a new surface, check the normals, and I still only get 1 hour of sun on a horizontal surface during the summer in Texas.

Please see attached images. Thank you again!

Hi Helena,

Attached a file where you can see point 2 working. The reason you get only one hour is because you defined only one hour in the sunpath component.

I updated the file to the last version.

I grouped in white color what i added for your convenience.

Defined one surface to cast shadows. Your geometry is not working for me either.

Hope it helps,

-A. (390 KB)


That shadow study component is under the WIP tab for a good reason. It’s very difficult to geometrically calculate vector shadows and I would only use that component for simple geometries like small numbers of boxes and planes. With geometry as complex as you have there, you are easily going to make your computer crash if you try to get it to work. I would instead suggest going with a raster-based method using the sunlight hours component.

Single Hour:

Over a day:

See example GH file attached.

-Chris (444 KB)

It works! Thanks a lot Abraham!

Thank you Chris!