HB and HB+ have different results when calculating DA of the same model

When performing DA analysis on a model, the ANN recipe using HB1.2.0 and HB+0.0.06 will produce different results, with a difference of 10%-20%. HB+ always seems to have better lighting conditions than HB, and the performance is more obvious after adding context, it seems The context of HB+ is translucent. I think this will have an impact on the my work. I want to know why, if it is my mistake, please help me to fix it.(new user can only upload one img.sry)

i really appreciate it!

Other pic for the problem here


did you check that you have in both analysis the same radiance parameters?

thx for reply .
I have no idea for radiance parameters. Do u mean these two settings? It seems including different parameters…

ok i learn about it .but can u tell me is there any module for the “dmtx_par”? or it need to type in a panel?

yep, those one should be the exact same.

for LB tool I’m using the following txt:

-aa 0.1 -ab 6 -ad 4096 -ar 128 -as 4096 -dc 0.75 -dj 1.0 -dp 512 -ds 0.05 -dr 3 -dt 0.15 -lr 8 -lw 4e-07 -ss 1.0 -st 0.15

I forgot how to impose those in HB+ but it is possible to do it also

Another thing (but I’m not sure and it would be great to have a confirmation from someone else) could be the normal vector of your surfaces. I think that they have the reflection value only in the direction of their normal. you are going to say “my geo are coming from the same input”. not totally true since you used the create_room object… it can change your surface direction.

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I make some change and recomputer the simulation but still not work .maybe i can upload the program here?

HBvsHB+ANNProblem.gh (104.1 KB)


there is something that I don’t get…

from the result file (.ill) if I’m not mistaken we should find the DA by counting the number of cell with a value higher than the threshold (300 lx) / the number of cell… Which represent the % of time with a higher value than 300 lx…

however this is not what I get in the .ill file…

so … have u got some ideas?is this an error or a new computing method ?And i suggested that u rebuild the program with HB 1.2.0 to make contrast between HB+ and HB if u have interest (to find out whether the difference just happen on my computer ) :grin:

have a good day!