latitude longitude polygon algorithm

[Zoidiasoft Tech]

Hi,

 

Does anyone have a generalized algorithm for finding whether a given point (latitude and longitude) is within a defined polygon?

 

Sincerely,

Curtis Manwaring

[Alois Treindl]

Please start here http://en.wikipedia.org/wiki/Point_in_polygon

I do not have a programmed algorithm at hand, but am confident to be
able to take it from published sources once I get to this particular
programming problem.

The topological problems however get more complex. Boundary polygons
alone are not enough, we need also topological information along with
them. Some zones have exclaves and enclaves, i.e. they consist of
several separated 'islands', or they have holes inside which are part of
another zone.

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[skylendar]

In that case, you may use GIS software (geographical information system) such
as postgis.
see http://postgis.refractions.net/