[Radiance-general] Getting number of pixels for fisheye view

[Lars O. Grobe]

> can't you work out which pixels are
> outside the view area by calculating the vv and vh
> of the pixel and comparing that with the value stored
> in the image header?
Well, I was thinking about doing that, but it is quite difficult to do
it. A pixel that sits "on the edge" is hard to count in this case, while
the pixel value, especially when used with a threshold, is easy to
extract and compare.

CU Lars.