Ladybug Radiation analysis very slow!

ladybug-tools
1

Greetings,

I’m trying to run a radiation analysis but it takes 8 minutes!
Am I doing something wrong?
Why such a long time to compute?

This is the GH script:

GH-Radiation
GH-Radiation2266×994 257 KB

This is my input:

image
image1867×853 62.3 KB

This is the result:

image
image1857×925 195 KB

The input is a mesh because with brep geometry it takes even more time.

2

Hi @Bogdan ,

Interesting: what makes you think it is overly slow? Have you run this model in another environment which is able to calculate it much more quickly than in Rhino/HB?

The model appears to me very, very comlicated - so I’m not at all surprised that it takes some time to calculate. But if you wanted to improve the calculation time, you can:

  • Simplify the model: Reduce the number of surfaces/elements, convert the curves to approximated planar faces
  • Extract a representative ‘portion’ of the model and simulate only that part (one quadrant, one layer, etc)
  • Upgrade the hardware/system that you are running then model on

Model calculation time is defined first and foremost by the number of surfaces in the model, so if you can reduce those by some means, that should speed up the calculation.

best,
@edpmay

3

Hi @edpmay ,

Thank you for your replay!
So this is the expected timeframe considering the model?

  • Simplify the model: Since I have it as a mesh, I should reduce the mesh faces count. Does this sound good?

What about seting up the Annalysis Period?

Thanks again…

4

I cannot say this is true for these particular components, but Ladybug components generally use very unoptimized Rhino ray-mesh intersection routines under the hood to do radiation analyses, while Honeybee components generally use the accelerated RADIANCE ray-tracing program. If you have a lot of analysis points and/or large meshes, the difference in runtime can be huge, by a factor of x100 or x1000, with the Ladybug components becoming very slow. Unfortunately, there is not always 1:1 replacements of Ladybug components with Honeybee components.

RADIANCE scales logarithmically, not linearly with scene complexity: if you have a mesh with 10 times the faces, it will not take 10 times as long to trace the rays (maybe only twice as long, or even less!).