# Occupant's view to the outdoors - ladybug component

Hello,

I try to determine the view to outdoor for four occupants in an office room. I assume that all the occupants look under 45 degree to the façade. I want to quantify the view to the outdoor with the “view to outdoor”- component in ladybug, but I don’t understand the results.
I have an office room with four occupants and vertical blinds as shading system. The room contains one big window in the south façade.
The vertical blinds have four possible states and I would to determine the view for each occupants and for each possible state. The squares in the image below represent the occupants.

I first determined the view for the occupants without shading system. But the view for the occupants 1 and 2 (see image below) is very different, but I would expect a more equal view.

Could anyone explain the “view to outdoor”-component and maybe give me advice how I can use this component to achieve my goal (correctly quantify the view for each of the four occupants and for different shading states)

Vertical_blinds_view_factor.gh (539.1 KB)

Kind regards,
Kim Bodde

Thank you for the information. I saw the example:

In the description of this example, they speak about the level of performance:
" For this file, a quality view is definied as an area with a view factor angle of 20 degrees or greater (or 2% of this full 360 field of view). This definition is taken from the View Factor Classification 4 presented in this research paper"

I have some questions and I hope that the answers makes makes the method more clear for me:

• What does a 2% level of performance mean? 2% of 360 isn’t to 20 degrees? Doesn’t the level of performance has to be minimal 5.55% to have a view angle of minimal 20 degrees? But why did they use 2%?
• Could you explain to me what the output ‘Area with a quality view’ means?

Kind regards,

Kim

Him @KimBodde,

I agree with you if the benchmark is 20 to 40 degrees it should be 5.55%. Can you please share that paper, the link not accessible anymore.

The “area with a quality view” is the area that meets that threshold on the “Ladybug_Mesh threshold selector” component.

Kind regards,

Hi everyone,I am also having doubt about 2 % threshold that has been talked about. @chris can you please explain this. How did this 2% was derived referencing to view analysis category in the research paper mentioned above?

Sorry for the late reply here. The reason why I used 2% instead of 5.6% is that we’re doing a 3D View analysis here (not a 2D one) and I took 20 degrees to be one dimension of the the solid angle of the view. So I interpret a “quality view” to be one that is 20 degrees by 20 degrees OR a non-square view with an solid angle equivalent to 20 deg x 20 deg.

2% makes sense when you consider that, when `_viewTypeOrPoints` is set to `1 - Horizontal 60 Degree Cone of Vision` on the “Ladybug_View Analysis” component, the component assumes a human field of view in the vertical dimension that is 60 degrees from top to bottom. This comes from several studies about human peripheral vision, though the boundaries of peripheral vision are a bit fuzzy and it’s admittedly a little subjective to say where exactly it ends. In any case, the factor-of-3 difference between 20 and 60 is what gives you the roughly factor-of-3 difference between 5.555 degrees and 2 degrees.

If you disagree with this interpretation of the LEED credit, you can always change the Ladybug View component to do a 2D analysis instead of a 3D one by setting `_viewTypeOrPoints` to `0 - Horizontal Radial`. Then the whole analysis will happen in the 2D XY plane and you should take 5.6% of the resulting vectors as the threshold for quality view.

But I think interpreting the LEED credit in terms of a solid angle is truer to the study that the credit is based on. After all, if we just gave a person a horizontal slit to look through that took up 20 degrees in the horizontal dimension, I doubt many of us would consider this a “quality view.”

1 Like

This makes sense perfectly. Thanks @Chris

Hi
I have one question about the view for LEED v4.
can we use 3D View analysis (set to -2- Horizontal 60 Degree Cone of Vision ) in hydra example?
or this is incorrect
thank you for attention