cgal-discuss - [cgal-discuss] question on CGAL::create_exterior_skeleton_and_offset_polygons_2

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From: Hoang Giang Bui <>
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Subject: [cgal-discuss] question on CGAL::create_exterior_skeleton_and_offset_polygons_2
Date: Fri, 15 Apr 2016 09:46:39 +0200
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Hello

I have a simple question. To create an offset polygon I used the code from examples:

Polygon_2 poly ;

poly.push_back( Point(0,0) ) ;

poly.push_back( Point(1,0) ) ;

poly.push_back( Point(1,1) ) ;

poly.push_back( Point(0,1) ) ;

FT lOffset = 0.1 ;

PolygonPtrVector outer_offset_polygons = CGAL::create_exterior_skeleton_and_offset_polygons_2(lOffset,poly);

print_polygons(outer_offset_polygons);

But it produces two polygons:

Polygon list with 2 polygons

Polygon with 4 vertices

(-0.146421,-0.146421)

(1.14642,-0.146421)

(1.14642,1.14642)

(-0.146421,1.14642)

Polygon with 4 vertices

(-0.1,1.1)

(1.1,1.1)

(1.1,-0.1)

(-0.1,-0.1)

The second is correct but the first seems hard to understand. Does anyone have idea what it is?

Giang

[cgal-discuss] question on CGAL::create_exterior_skeleton_and_offset_polygons_2, Hoang Giang Bui, 04/15/2016
- Re: [cgal-discuss] question on CGAL::create_exterior_skeleton_and_offset_polygons_2, Sebastien Loriot (GeometryFactory), 04/15/2016
  - Re: [cgal-discuss] question on CGAL::create_exterior_skeleton_and_offset_polygons_2, Hoang Giang Bui, 04/16/2016