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//----------------------------------------------------------------------------
// 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
//----------------------------------------------------------------------------
#include "agg_vcgen_bspline.h"
namespace agg
{
//------------------------------------------------------------------------
vcgen_bspline::vcgen_bspline() :
m_src_vertices(),
m_spline_x(),
m_spline_y(),
m_interpolation_step(1.0/50.0),
m_closed(0),
m_status(initial),
m_src_vertex(0)
{
}
//------------------------------------------------------------------------
void vcgen_bspline::remove_all()
{
m_src_vertices.remove_all();
m_closed = 0;
m_status = initial;
m_src_vertex = 0;
}
//------------------------------------------------------------------------
void vcgen_bspline::add_vertex(double x, double y, unsigned cmd)
{
m_status = initial;
if(is_move_to(cmd))
{
m_src_vertices.modify_last(point_d(x, y));
}
else
{
if(is_vertex(cmd))
{
m_src_vertices.add(point_d(x, y));
}
else
{
m_closed = get_close_flag(cmd);
}
}
}
//------------------------------------------------------------------------
void vcgen_bspline::rewind(unsigned)
{
m_cur_abscissa = 0.0;
m_max_abscissa = 0.0;
m_src_vertex = 0;
if(m_status == initial && m_src_vertices.size() > 2)
{
if(m_closed)
{
m_spline_x.init(m_src_vertices.size() + 8);
m_spline_y.init(m_src_vertices.size() + 8);
m_spline_x.add_point(0.0, m_src_vertices.prev(m_src_vertices.size() - 3).x);
m_spline_y.add_point(0.0, m_src_vertices.prev(m_src_vertices.size() - 3).y);
m_spline_x.add_point(1.0, m_src_vertices[m_src_vertices.size() - 3].x);
m_spline_y.add_point(1.0, m_src_vertices[m_src_vertices.size() - 3].y);
m_spline_x.add_point(2.0, m_src_vertices[m_src_vertices.size() - 2].x);
m_spline_y.add_point(2.0, m_src_vertices[m_src_vertices.size() - 2].y);
m_spline_x.add_point(3.0, m_src_vertices[m_src_vertices.size() - 1].x);
m_spline_y.add_point(3.0, m_src_vertices[m_src_vertices.size() - 1].y);
}
else
{
m_spline_x.init(m_src_vertices.size());
m_spline_y.init(m_src_vertices.size());
}
unsigned i;
for(i = 0; i < m_src_vertices.size(); i++)
{
double x = m_closed ? i + 4 : i;
m_spline_x.add_point(x, m_src_vertices[i].x);
m_spline_y.add_point(x, m_src_vertices[i].y);
}
m_cur_abscissa = 0.0;
m_max_abscissa = m_src_vertices.size() - 1;
if(m_closed)
{
m_cur_abscissa = 4.0;
m_max_abscissa += 5.0;
m_spline_x.add_point(m_src_vertices.size() + 4, m_src_vertices[0].x);
m_spline_y.add_point(m_src_vertices.size() + 4, m_src_vertices[0].y);
m_spline_x.add_point(m_src_vertices.size() + 5, m_src_vertices[1].x);
m_spline_y.add_point(m_src_vertices.size() + 5, m_src_vertices[1].y);
m_spline_x.add_point(m_src_vertices.size() + 6, m_src_vertices[2].x);
m_spline_y.add_point(m_src_vertices.size() + 6, m_src_vertices[2].y);
m_spline_x.add_point(m_src_vertices.size() + 7, m_src_vertices.next(2).x);
m_spline_y.add_point(m_src_vertices.size() + 7, m_src_vertices.next(2).y);
}
m_spline_x.prepare();
m_spline_y.prepare();
}
m_status = ready;
}
//------------------------------------------------------------------------
unsigned vcgen_bspline::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)
{
cmd = path_cmd_stop;
break;
}
if(m_src_vertices.size() == 2)
{
*x = m_src_vertices[m_src_vertex].x;
*y = m_src_vertices[m_src_vertex].y;
m_src_vertex++;
if(m_src_vertex == 1) return path_cmd_move_to;
if(m_src_vertex == 2) return path_cmd_line_to;
cmd = path_cmd_stop;
break;
}
cmd = path_cmd_move_to;
m_status = polygon;
m_src_vertex = 0;
case polygon:
if(m_cur_abscissa >= m_max_abscissa)
{
if(m_closed)
{
m_status = end_poly;
break;
}
else
{
*x = m_src_vertices[m_src_vertices.size() - 1].x;
*y = m_src_vertices[m_src_vertices.size() - 1].y;
m_status = end_poly;
return path_cmd_line_to;
}
}
*x = m_spline_x.get_stateful(m_cur_abscissa);
*y = m_spline_y.get_stateful(m_cur_abscissa);
m_src_vertex++;
m_cur_abscissa += m_interpolation_step;
return (m_src_vertex == 1) ? path_cmd_move_to : path_cmd_line_to;
case end_poly:
m_status = stop;
return path_cmd_end_poly | m_closed;
case stop:
return path_cmd_stop;
}
}
return cmd;
}
}