ultimatepp/uppdev/aggdraw/agg_vpgen_clip_polyline.cpp

86 lines
2.8 KiB
C++

//----------------------------------------------------------------------------
// Anti-Grain Geometry (AGG) - Version 2.5
// A high quality rendering engine for C++
// Copyright (C) 2002-2006 Maxim Shemanarev
// Contact: mcseem@antigrain.com
// mcseemagg@yahoo.com
// http://antigrain.com
//
// AGG is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// AGG is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with AGG; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
// MA 02110-1301, USA.
//----------------------------------------------------------------------------
#include "agg_vpgen_clip_polyline.h"
#include "agg_clip_liang_barsky.h"
namespace agg
{
//----------------------------------------------------------------------------
void vpgen_clip_polyline::reset()
{
m_vertex = 0;
m_num_vertices = 0;
m_move_to = false;
}
//----------------------------------------------------------------------------
void vpgen_clip_polyline::move_to(double x, double y)
{
m_vertex = 0;
m_num_vertices = 0;
m_x1 = x;
m_y1 = y;
m_move_to = true;
}
//----------------------------------------------------------------------------
void vpgen_clip_polyline::line_to(double x, double y)
{
double x2 = x;
double y2 = y;
unsigned flags = clip_line_segment(&m_x1, &m_y1, &x2, &y2, m_clip_box);
m_vertex = 0;
m_num_vertices = 0;
if((flags & 4) == 0)
{
if((flags & 1) != 0 || m_move_to)
{
m_x[0] = m_x1;
m_y[0] = m_y1;
m_cmd[0] = path_cmd_move_to;
m_num_vertices = 1;
}
m_x[m_num_vertices] = x2;
m_y[m_num_vertices] = y2;
m_cmd[m_num_vertices++] = path_cmd_line_to;
m_move_to = (flags & 2) != 0;
}
m_x1 = x;
m_y1 = y;
}
//----------------------------------------------------------------------------
unsigned vpgen_clip_polyline::vertex(double* x, double* y)
{
if(m_vertex < m_num_vertices)
{
*x = m_x[m_vertex];
*y = m_y[m_vertex];
return m_cmd[m_vertex++];
}
return path_cmd_stop;
}
}