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Re: ANNOUNCE: gpc general polygon clipping library available
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maheshna...@gmail.com
Oct 7, 2016, 4:45:59 AM10/7/16
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On Sunday, November 12, 2000 at 1:30:00 PM UTC+5:30, Toby Howard wrote:
> The gpc polygon clipping library (v2.31) is available from:
>
> http://www.cs.man.ac.uk/aig/staff/alan/software/index.html
>
> It is written in C, and has the following features:
>
> * Difference, intersection, exclusive-or and union clip
> operations are supported.
>
> * Polygons may be comprised of multiple disjoint contours.
>
> * Contour vertices may be given in any order - clockwise or
> anticlockwise.
>
> * Contours may be convex, concave or self-intersecting.
>
> * Contours may be nested (i.e. polygons may have holes).
>
> * Output may take the form of either polygon contours or
> tristrips.
>
> * Hole and external contours are differentiated in the
> result.
>
> * Coincident edges and degenerate regions are handled
> correctly.
>
> Even if you don't require a polygon clipper you may find
> gpc useful for:
>
> * Triangulating (with tristrips) an arbitrary set of
> polygon contours (self-intersecting, holes etc).
>
> * Converting self-intersecting polygon contours to a
> set of non-intersecting contours.
>
> * Seamlessly merging polygons which share common edges.
>
> * Performing a polygon-in-polygon test.
>
>
> This software is free for non-commercial use. Anyone wishing to use the gpc
> library in support of a commercial product please email g...@cs.man.ac.uk.
>
> Alan Murta
>
> -------------------------------------------------------------------
> Alan Murta Computer Science Department, University of Manchester,
> Lecturer Manchester, M13 9PL, UK. Tel: +44 (0)161-275-6259
> E-mail: amu...@cs.man.ac.uk Fax: +44 (0)161-275-6236
> World Wide Web: http://www.cs.man.ac.uk/aig/staff/alan
> -------------------------------------------------------------------
The version at the University has serious faults .the triangulation output is wrong at the last step if the left and right arms of the strip are of unequal length. The Code for EMX is also wrong in rare cases.
> The gpc polygon clipping library (v2.31) is available from:
>
> http://www.cs.man.ac.uk/aig/staff/alan/software/index.html
>
> It is written in C, and has the following features:
>
> * Difference, intersection, exclusive-or and union clip
> operations are supported.
>
> * Polygons may be comprised of multiple disjoint contours.
>
> * Contour vertices may be given in any order - clockwise or
> anticlockwise.
>
> * Contours may be convex, concave or self-intersecting.
>
> * Contours may be nested (i.e. polygons may have holes).
>
> * Output may take the form of either polygon contours or
> tristrips.
>
> * Hole and external contours are differentiated in the
> result.
>
> * Coincident edges and degenerate regions are handled
> correctly.
>
> Even if you don't require a polygon clipper you may find
> gpc useful for:
>
> * Triangulating (with tristrips) an arbitrary set of
> polygon contours (self-intersecting, holes etc).
>
> * Converting self-intersecting polygon contours to a
> set of non-intersecting contours.
>
> * Seamlessly merging polygons which share common edges.
>
> * Performing a polygon-in-polygon test.
>
>
> This software is free for non-commercial use. Anyone wishing to use the gpc
> library in support of a commercial product please email g...@cs.man.ac.uk.
>
> Alan Murta
>
> -------------------------------------------------------------------
> Alan Murta Computer Science Department, University of Manchester,
> Lecturer Manchester, M13 9PL, UK. Tel: +44 (0)161-275-6259
> E-mail: amu...@cs.man.ac.uk Fax: +44 (0)161-275-6236
> World Wide Web: http://www.cs.man.ac.uk/aig/staff/alan
> -------------------------------------------------------------------
The version at the University has serious faults .the triangulation output is wrong at the last step if the left and right arms of the strip are of unequal length. The Code for EMX is also wrong in rare cases.
Leclerc
Oct 7, 2016, 5:01:31 AM10/7/16
to maheshna...@gmail.com
You are aware that you are responding to almost 16 years old post?
Mahesh Naik
Oct 25, 2020, 4:22:10 PM10/25/20
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