Tangent from a point to a polygon

Tangent from a point to a polygon

I've to find the way to create a polygon that represent the invisibility
of one point made by a polygon. In few words I've to find the tangent
between one point and a polygon. Just to be much more clear take a look at :

http://geometryalgorithms.com/Archive/algorithm_0201/algorithm_0201.htm#Tangents:%20Point%20to%20Polygon

Tnx in advance

P.s. I can't use the raster approach.

What is your question? It seems like the link you posted has the answers.

You are right but i'm not able to convert the solution in vba, i've to
do it in arcgis and i've some problem with it. Could you help me ?

Sorry, I'm afraid I am not fluent in either vba or arcgis.

Maybe somebody else in this newsgroup will help. Good luck.

Bob

Bob (Robert G.) Chamberlain | I am a great believer in luck,
rgc@jpl.nasa.gov | and I find the harder I work,
Opinions & quips are mine | the more I have of it.
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