Points, Lines, and Polygons on Spheres with C/C++ -

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my application represent shapes on earth's (using sphere sufficient) surface. can points, lines, , polygons. coordinates should defined using degrees or radians (just geographic coordinates).

a line segment between 2 points on surface of sphere should lie on great circle. polygons should consist of collection of such lines. furthermore, perform set - basic operations intersection, union, difference, complement on shapes mentioned. these operations need output collections of points.

i tried figure out using cgal's 3d spherical geometry kernel , 2d boolean operations on nef polygons embedded on sphere. actually, had problems putting line on sphere. additionally cgal works in euclidean space, still leaves me geometric operations necessary, work great circles placed on sphere.

my question is, if can assist me in realizing functionality mentioned in cgal or if can recommend library c/c++ that. thank much!

i'd suggest take @ this:

http://www.codeguru.com/cpp/cpp/algorithms/general/article.php/c5115/

the question 1e solves problem of intersection between 2 grand circles. can define basic operation of shapes on sphere without big dependency cgal or geos.


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