agg/src/agg_vcgen_contour.cpp

165 lines
5.0 KiB
C++

//----------------------------------------------------------------------------
// Anti-Grain Geometry - Version 2.4
// 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
//----------------------------------------------------------------------------
//
// Contour generator
//
//----------------------------------------------------------------------------
#include "agg_vcgen_contour.h"
namespace agg
{
//------------------------------------------------------------------------
vcgen_contour::vcgen_contour() :
m_stroker(),
m_width(1),
m_src_vertices(),
m_out_vertices(),
m_status(initial),
m_src_vertex(0),
m_closed(0),
m_orientation(0),
m_auto_detect(false)
{
}
//------------------------------------------------------------------------
void vcgen_contour::remove_all()
{
m_src_vertices.remove_all();
m_closed = 0;
m_orientation = 0;
m_status = initial;
}
//------------------------------------------------------------------------
void vcgen_contour::add_vertex(double x, double y, unsigned cmd)
{
m_status = initial;
if(is_move_to(cmd))
{
m_src_vertices.modify_last(vertex_dist(x, y));
}
else
{
if(is_vertex(cmd))
{
m_src_vertices.add(vertex_dist(x, y));
}
else
{
if(is_end_poly(cmd))
{
m_closed = get_close_flag(cmd);
if(m_orientation == path_flags_none)
{
m_orientation = get_orientation(cmd);
}
}
}
}
}
//------------------------------------------------------------------------
void vcgen_contour::rewind(unsigned)
{
if(m_status == initial)
{
m_src_vertices.close(true);
if(m_auto_detect)
{
if(!is_oriented(m_orientation))
{
m_orientation = (calc_polygon_area(m_src_vertices) > 0.0) ?
path_flags_ccw :
path_flags_cw;
}
}
if(is_oriented(m_orientation))
{
m_stroker.width(is_ccw(m_orientation) ? m_width : -m_width);
}
}
m_status = ready;
m_src_vertex = 0;
}
//------------------------------------------------------------------------
unsigned vcgen_contour::vertex(double* x, double* y)
{
unsigned cmd = path_cmd_line_to;
while(!is_stop(cmd))
{
switch(m_status)
{
case initial:
rewind(0);
case ready:
if(m_src_vertices.size() < 2 + unsigned(m_closed != 0))
{
cmd = path_cmd_stop;
break;
}
m_status = outline;
cmd = path_cmd_move_to;
m_src_vertex = 0;
m_out_vertex = 0;
case outline:
if(m_src_vertex >= m_src_vertices.size())
{
m_status = end_poly;
break;
}
m_stroker.calc_join(m_out_vertices,
m_src_vertices.prev(m_src_vertex),
m_src_vertices.curr(m_src_vertex),
m_src_vertices.next(m_src_vertex),
m_src_vertices.prev(m_src_vertex).dist,
m_src_vertices.curr(m_src_vertex).dist);
++m_src_vertex;
m_status = out_vertices;
m_out_vertex = 0;
case out_vertices:
if(m_out_vertex >= m_out_vertices.size())
{
m_status = outline;
}
else
{
const point_d& c = m_out_vertices[m_out_vertex++];
*x = c.x;
*y = c.y;
return cmd;
}
break;
case end_poly:
if(!m_closed) return path_cmd_stop;
m_status = stop;
return path_cmd_end_poly | path_flags_close | path_flags_ccw;
case stop:
return path_cmd_stop;
}
}
return cmd;
}
}