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Re: [cgal-discuss] CGAL::Polygon_mesh_processing::clip returns self itersecting mesh

From: "Sebastien Loriot (GeometryFactory)" <>
To:
Subject: Re: [cgal-discuss] CGAL::Polygon_mesh_processing::clip returns self itersecting mesh
Date: Fri, 24 Jan 2020 16:39:26 +0100
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For the clipping there is a double rounding issue:
It first cut the extended bbox of the mesh with the plane (first rounding) and then do the operation (second rounding).

Sebastien.

On 1/24/20 4:37 PM, slidertom wrote:

I miss typed:
//K::Point_3 plane_pt(0., 2., 0.);
it must be:
//K::Point_3 plane_pt(0., 0.2, 0.);
as:
K::Point_3 plane_pt(0., 0.19999999999999987, 0.);

Just realized, this is probably "edge/rounding" issue:
(0., 2., 0.) generates plane which touch edge
and
(0., 0.19999999999999987, 0.) generates plane which is inside mesh.

CGAL does very precise calculations and result is self intersecting mesh.

--
Sent from: http://cgal-discuss.949826.n4.nabble.com/

[cgal-discuss] CGAL::Polygon_mesh_processing::clip returns self itersecting mesh, slidertom, 01/23/2020
- Re: [cgal-discuss] CGAL::Polygon_mesh_processing::clip returns self itersecting mesh, Sebastien Loriot (GeometryFactory), 01/24/2020
  - Re: [cgal-discuss] CGAL::Polygon_mesh_processing::clip returns self itersecting mesh, slidertom, 01/24/2020
    - Re: [cgal-discuss] CGAL::Polygon_mesh_processing::clip returns self itersecting mesh, slidertom, 01/24/2020
      - Re: [cgal-discuss] CGAL::Polygon_mesh_processing::clip returns self itersecting mesh, Sebastien Loriot (GeometryFactory), 01/24/2020

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Re: [cgal-discuss] CGAL::Polygon_mesh_processing::clip returns self itersecting mesh