67 lines
2 KiB
C
67 lines
2 KiB
C
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//----------------------------------------------------------------------------
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// Anti-Grain Geometry - Version 2.4
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// Copyright (C) 2002-2005 Maxim Shemanarev (http://www.antigrain.com)
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//
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// Permission to copy, use, modify, sell and distribute this software
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// is granted provided this copyright notice appears in all copies.
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// This software is provided "as is" without express or implied
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// warranty, and with no claim as to its suitability for any purpose.
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//
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//----------------------------------------------------------------------------
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// Contact: mcseem@antigrain.com
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// mcseemagg@yahoo.com
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// http://www.antigrain.com
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//----------------------------------------------------------------------------
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#ifndef AGG_SHORTEN_PATH_INCLUDED
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#define AGG_SHORTEN_PATH_INCLUDED
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#include "agg_basics.h"
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#include "agg_vertex_sequence.h"
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namespace agg
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{
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//===========================================================shorten_path
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template<class VertexSequence>
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void shorten_path(VertexSequence& vs, double s, unsigned closed = 0)
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{
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typedef typename VertexSequence::value_type vertex_type;
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if(s > 0.0 && vs.size() > 1)
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{
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double d;
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int n = int(vs.size() - 2);
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while(n)
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{
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d = vs[n].dist;
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if(d > s) break;
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vs.remove_last();
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s -= d;
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--n;
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}
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if(vs.size() < 2)
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{
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vs.remove_all();
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}
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else
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{
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n = vs.size() - 1;
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vertex_type& prev = vs[n-1];
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vertex_type& last = vs[n];
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d = (prev.dist - s) / prev.dist;
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double x = prev.x + (last.x - prev.x) * d;
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double y = prev.y + (last.y - prev.y) * d;
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last.x = x;
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last.y = y;
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if(!prev(last)) vs.remove_last();
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vs.close(closed != 0);
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}
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}
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}
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}
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#endif
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