office-gobmx/agg/inc/agg_conv_clip_polygon.h

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2.7 KiB
C++
Executable file

//----------------------------------------------------------------------------
// Anti-Grain Geometry - Version 2.3
// Copyright (C) 2002-2005 Maxim Shemanarev (http://www.antigrain.com)
//
// Permission to copy, use, modify, sell and distribute this software
// is granted provided this copyright notice appears in all copies.
// This software is provided "as is" without express or implied
// warranty, and with no claim as to its suitability for any purpose.
//
//----------------------------------------------------------------------------
// Contact: mcseem@antigrain.com
// mcseemagg@yahoo.com
// http://www.antigrain.com
//----------------------------------------------------------------------------
//
// Polygon clipping converter
// There an optimized Liang-Basky algorithm is used.
// The algorithm doesn't optimize the degenerate edges, i.e. it will never
// break a closed polygon into two or more ones, instead, there will be
// degenerate edges coinciding with the respective clipping boundaries.
// This is a sub-optimal solution, because that optimization would require
// extra, rather expensive math while the rasterizer tolerates it quite well,
// without any considerable overhead.
//
//----------------------------------------------------------------------------
#ifndef AGG_CONV_CLIP_POLYGON_INCLUDED
#define AGG_CONV_CLIP_POLYGON_INCLUDED
#include "agg_basics.h"
#include "agg_conv_adaptor_vpgen.h"
#include "agg_vpgen_clip_polygon.h"
#include "agg_vertex_iterator.h"
namespace agg
{
//=======================================================conv_clip_polygon
template<class VertexSource>
struct conv_clip_polygon : public conv_adaptor_vpgen<VertexSource, vpgen_clip_polygon>
{
typedef conv_adaptor_vpgen<VertexSource, vpgen_clip_polygon> base_type;
conv_clip_polygon(VertexSource& vs) :
conv_adaptor_vpgen<VertexSource, vpgen_clip_polygon>(vs) {}
void clip_box(double x1, double y1, double x2, double y2)
{
base_type::vpgen().clip_box(x1, y1, x2, y2);
}
double x1() const { return base_type::vpgen().x1(); }
double y1() const { return base_type::vpgen().y1(); }
double x2() const { return base_type::vpgen().x2(); }
double y2() const { return base_type::vpgen().y2(); }
typedef conv_clip_polygon<VertexSource> source_type;
typedef vertex_iterator<source_type> iterator;
iterator begin(unsigned id) { return iterator(*this, id); }
iterator end() { return iterator(path_cmd_stop); }
private:
conv_clip_polygon(const conv_clip_polygon<VertexSource>&);
const conv_clip_polygon<VertexSource>&
operator = (const conv_clip_polygon<VertexSource>&);
};
}
#endif