mapnik/deps/agg/src/agg_arrowhead.cpp

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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
//----------------------------------------------------------------------------
//
// Simple arrowhead/arrowtail generator
//
//----------------------------------------------------------------------------
#include "agg_arrowhead.h"
namespace agg
{
//------------------------------------------------------------------------
arrowhead::arrowhead() :
m_head_d1(1.0),
m_head_d2(1.0),
m_head_d3(1.0),
m_head_d4(0.0),
m_tail_d1(1.0),
m_tail_d2(1.0),
m_tail_d3(1.0),
m_tail_d4(0.0),
m_head_flag(false),
m_tail_flag(false),
m_curr_id(0),
m_curr_coord(0)
{
}
//------------------------------------------------------------------------
void arrowhead::rewind(unsigned path_id)
{
m_curr_id = path_id;
m_curr_coord = 0;
if(path_id == 0)
{
if(!m_tail_flag)
{
m_cmd[0] = path_cmd_stop;
return;
}
m_coord[0] = m_tail_d1; m_coord[1] = 0.0;
m_coord[2] = m_tail_d1 - m_tail_d4; m_coord[3] = m_tail_d3;
m_coord[4] = -m_tail_d2 - m_tail_d4; m_coord[5] = m_tail_d3;
m_coord[6] = -m_tail_d2; m_coord[7] = 0.0;
m_coord[8] = -m_tail_d2 - m_tail_d4; m_coord[9] = -m_tail_d3;
m_coord[10] = m_tail_d1 - m_tail_d4; m_coord[11] = -m_tail_d3;
m_cmd[0] = path_cmd_move_to;
m_cmd[1] = path_cmd_line_to;
m_cmd[2] = path_cmd_line_to;
m_cmd[3] = path_cmd_line_to;
m_cmd[4] = path_cmd_line_to;
m_cmd[5] = path_cmd_line_to;
m_cmd[7] = path_cmd_end_poly | path_flags_close | path_flags_ccw;
m_cmd[6] = path_cmd_stop;
return;
}
if(path_id == 1)
{
if(!m_head_flag)
{
m_cmd[0] = path_cmd_stop;
return;
}
m_coord[0] = -m_head_d1; m_coord[1] = 0.0;
m_coord[2] = m_head_d2 + m_head_d4; m_coord[3] = -m_head_d3;
m_coord[4] = m_head_d2; m_coord[5] = 0.0;
m_coord[6] = m_head_d2 + m_head_d4; m_coord[7] = m_head_d3;
m_cmd[0] = path_cmd_move_to;
m_cmd[1] = path_cmd_line_to;
m_cmd[2] = path_cmd_line_to;
m_cmd[3] = path_cmd_line_to;
m_cmd[4] = path_cmd_end_poly | path_flags_close | path_flags_ccw;
m_cmd[5] = path_cmd_stop;
return;
}
}
//------------------------------------------------------------------------
unsigned arrowhead::vertex(double* x, double* y)
{
if(m_curr_id < 2)
{
unsigned curr_idx = m_curr_coord * 2;
*x = m_coord[curr_idx];
*y = m_coord[curr_idx + 1];
return m_cmd[m_curr_coord++];
}
return path_cmd_stop;
}
}