Ladybug sunshades calculator

Hello All,

I’m making shading for the window, I don’t know why there is a gap between the shading bar and the wall when I specify the shape of the surface to it, I also want to ask if this is related to the setting of udiv and offestfactor?

Thank you!! (478.5 KB)

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Hi @fanxin,
Can you upload your file so i can take a look?
This can be caused bacouse of the period of time you asked for … but want to be sure.

@AbrahamYezioro I have uploaded the file. Thank you!!

Hello @fanxin, It appears that you’re missing an avatar! Please set it up in your profile! Thanks. :slight_smile:

@admin I’m sorry. It seems that I didn’t miss it. When you reconnect the surface, it works.

@fanxin In my project practices, Ladybug_Sun_Shades_Calculator component is not using for generating the shading surface. I usually used the Ladybug_ShadingDesigner.
Here is the picture of Ladybug_ShadingDesigner .

And this is shading surface of your project and the gh file. (494.9 KB)

Hope it can help you.

@minggangyin Thank you very much. Whether the method in the picture is closer to my idea to calculate the reasonable shading form?

@fanxin I cannot get your idea about reasonable shading form. If you have different shading form( not shading surface),you need to calculate the solar radiation of them. Then according to the result, selected the best-fit one.

@fanxin and @minggangyin,
There can be many approaches to calculate/get the shading surface.
The LB_SunShades_Calc is one approach, and i believe the one that can improve or trigger the creativity of the designer. Just imagine that 2 users using the LB__ShadingDesigner for the same problem. They will get the exact same solution under the same constraints. The SunshadeCalculator enables to explore and get various solutions for the same problem, providing the same performance.
Needless to say that you can still implement radiation checkings here.
@fanxin: Attached an updated version of your file. The gap was produced because a surface normal situation (you are using a curved shadeSurface. Just lifted it a bit in Z direction and now works fine. Check the red arrows and group for my changes. You were using 3 times vectors because of the multiple center points provided to the SunPath. Also “play” a bit with the CullingPoints input. For your case i set to “No Cull” for better results.
Enjoy and glad you are using this component.
-A. (492.2 KB)

Just to add to the thread. This BS2011_Shaderade.pdf (1.8 MB)
is the most referred paper when it comes to shading design. It clearly shows all the ways you can define a shading.

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Good one @devang,
If we are here there is another, much more pioneer paper back to 1975 from Edna Shaviv (my tutor):

Shaviv E., 1975. “A Method for the Design of Fixed External Sun-Shades”. “Build International” (8), Applied Science Publishers LTD, England, (pp.121-150).

Which suggested an “envelope” of solutions to shade windows. Hopefully i will integrate this approach in the SunshadesCalculator. Unfortunately Reinhart didn’t mentioned this approach and exceptional work in the paper you cited above, even though he did an extensive review of background works.
Attached the paper FYI (is not easy to get the paper).
A Method For The Design of Fixed External Sun Shades.pdf (7.7 MB)


Wow! @AbrahamYezioro,
Thanks a lot for sharing! I would love to read this. Really appreciated.

This is what I really love about this community where people with a great amount of experience such as yourself can provide different perspectives on popular matters.

Thank you very much!:grin:

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Thank you very much!! In fact, I’m a newcomer and I don’t quite understand the meaning of these three parameters after I read the instructions: culling points, offest factor,udiv. I would appreciate it if you could explain them a little bit.

I also request you to kindly elaborate the descriptions for inputs and outputs. I too remember spending time trying to understand the role of inputs. It would be really appreciated if you could elaborate them inside the component and send a PR please.

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I will try.
The thing is that those parameters don’t have an absolute influence for all cases but rather they depend on the specific case. For @fanxin the cullRes gave better results when set to none. For other cases setting other value will also give very good results. I suggest to show the cullPts output to understand better (is very cool also and a lot can be learned from just seeing those points. Also the context points.
The offsetFactor is also a subtle one. It affects the contour of the shading surface (smoother or straight). Also here depending on the case the input value can affect more or less.
Hope this helps … in the meantime.

Forgot to mention. The udiv input is intended for window resolution: How many division do you want to have in your window. This may improve the accuracy of the calculated shading device. No need to get crazy here. Start with a low value, and if needed rise it.

@AbrahamYezioro I would like to ask one more question. I specify another surface shape today, but the calculation is very strange, can it calculate the u shape now?

Can you upload your file @fanxin?
Not sure what is your question. You want to know how to cut the U shaped surface?