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[Marko Kukovec <>]

Your guess was right! I can't belief I didn't see it by myself. 

Thank you again!

Marko


-----Original Message-----
From: Ophir Setter <>
Reply-To: 
To: 
Subject: Re: [cgal-discuss] 2D Regularized Boolean Set-Operations
Date: Wed, 30 Apr 2008 13:43:45 +0300

The constructor of Circle_2 usually gets the squared radius and not the radius itself.
My guess is that this is the problem.


On Wed, Apr 30, 2008 at 12:22 PM, Marko Kukovec <> wrote:
>     Hello!
>     
>     I'm new to the usage of the CGAL library. I'm especially interested in
>     the "2D Regularized Boolean Set-Operations" so I went trough all the
>     examples in the documentation. I have a question regarding example in
>     the "14.3.2 Operating on Polygons with Circular Arcs"
>     http://www.cgal.org/Manual/3.3/examples/Boolean_set_operations_2/circle_segment.cpp
>     
>     when I execute the example with the values presented I get correct
>     result:
>     
>     { Outer boundary =
>     [ 8 curves:
>     start (0, 5) --> end (0, 1)
>     start (0, 1) --> end (1, 0)
>        circle center(1, 1), radious(1), orientation(1)
>     start (1, 0) --> end (5, 0)
>     start (5, 0) --> end (6, 1)
>        circle center(5, 1), radious(1), orientation(1)
>     start (6, 1) --> end (6, 5)
>     start (6, 5) --> end (5, 6)
>        circle center(5, 5), radious(1), orientation(1)
>     start (5, 6) --> end (1, 6)
>     start (1, 6) --> end (0, 5)
>        circle center(1, 5), radious(1), orientation(1)
>      1 holes:
>        Hole #1 = [ 4 curves:
>     start (2, 4) --> end (4, 4)
>     start (4, 4) --> end (4, 2)
>     start (4, 2) --> end (2, 2)
>     start (2, 2) --> end (2, 4)
>     }
>     
>     Picture:
>     http://img138.imageshack.us/img138/5940/goodresultsrf7.jpg
>     
>     
>     but when I multiply input data by 100, result is wrong
>     
>      circ1 = construct_polygon(Circle_2(Point_2(100, 100), 100));
>     S.insert(circ1);
>      circ2 = construct_polygon(Circle_2(Point_2(500, 100), 100));
>     S.insert(circ2);
>      circ3 = construct_polygon(Circle_2(Point_2(500, 500), 100));
>     S.insert(circ3);
>      circ4 = construct_polygon(Circle_2(Point_2(100, 500), 100));
>     S.insert(circ4);
>     
>      // Compute the union with four rectangles incrementally.
>      Polygon_2 rect1, rect2, rect3, rect4;
>     
>      rect1 = construct_polygon(Point_2(100, 0), Point_2(500, 0),
>                                Point_2(500, 200), Point_2(100, 200));
>      S.join (rect1);
>     
>      rect2 = construct_polygon(Point_2(100, 400), Point_2(500, 400),
>                                Point_2(500, 600), Point_2(100, 600));
>      S.join (rect2);
>     
>      rect3 = construct_polygon(Point_2(0, 100), Point_2(200, 100),
>                                Point_2(200, 500), Point_2(0, 500));
>      S.join (rect3);
>     
>      rect4 = construct_polygon(Point_2(400, 100), Point_2(600, 100),
>                                Point_2(600, 500), Point_2(400, 500));
>     
>     Result:
>     
>     { Outer boundary =
>     [ 16 curves:
>     start (600, 500) --> end (510, 500)
>     start (510, 500) --> end (500, 510)
>        circle center(500, 500), radious(10), orientation(1)
>     start (500, 510) --> end (500, 600)
>     start (500, 600) --> end (100, 600)
>     start (100, 600) --> end (100, 510)
>     start (100, 510) --> end (90, 500)
>        circle center(100, 500), radious(10), orientation(1)
>     start (90, 500) --> end (0, 500)
>     start (0, 500) --> end (0, 100)
>     start (0, 100) --> end (90, 100)
>     start (90, 100) --> end (100, 90)
>        circle center(100, 100), radious(10), orientation(1)
>     start (100, 90) --> end (100, 0)
>     start (100, 0) --> end (500, 0)
>     start (500, 0) --> end (500, 90)
>     start (500, 90) --> end (510, 100)
>        circle center(500, 100), radious(10), orientation(1)
>     start (510, 100) --> end (600, 100)
>     start (600, 100) --> end (600, 500)
>      1 holes:
>        Hole #1 = [ 4 curves:
>     start (200, 400) --> end (400, 400)
>     start (400, 400) --> end (400, 200)
>     start (400, 200) --> end (200, 200)
>     start (200, 200) --> end (200, 400)
>     }
>     
>     Picture:
>     http://img138.imageshack.us/img138/7459/wrongresultslz1.jpg
>     
>     
>     I don't understand why? Shouldn't I get the same number of curves in the
>     result but proportionally bigger?
>     
>     Thank you for all the help.
>     
>     Regards,
>     Marko Kukovec
>     
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