Hello
I want to calculate the solid angle of a facade as seen through a window.
To do this, I drew straight lines from the viewpoint toward the four corners of the window(figure 1). Then, I extended those lines until they intersected with the plane of the facade, and used the projected points to form a quadrilateral(figure 2). Using this quadrilateral, I split the facade geometry.
However, a problem arises when the angle between the view direction and the facade plane becomes too large. In such cases, the projected quadrilateral cannot be formed correctly, making it impossible to split the facade.(figure 3)
I would like to solve this issue.
Is there an established method for calculating the solid angle of such a visible portion of a surface, especially in situations like this?
Thank you.
parametric study solid angle.gh (137.5 KB)