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//----------------------------------------------------------------------------
// XYQ: 2006-01-22 Copied from AGG project.
// TODO: This file uses intensive floating point operations, so it's NOT suitable
// for platforms like Symbian OS. We need to change to FIX format.
//----------------------------------------------------------------------------
//----------------------------------------------------------------------------
// 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
//----------------------------------------------------------------------------
//
// Stroke generator
//
//----------------------------------------------------------------------------
#include "agg_vcgen_stroke.h"
namespace agg
{
vcgen_stroke::vcgen_stroke() :
m_src_vertices(),
m_out_vertices(),
m_width(0.5f),
m_miter_limit(4 * 1.0f),
m_inner_miter_limit(1.0f + 1.0f / 100),
m_approx_scale(1.0f),
m_line_cap(butt_cap),
m_line_join(miter_join),
m_inner_join(inner_miter),
m_closed(0),
m_status(initial),
m_src_vertex(0),
m_out_vertex(0)
{
}
void vcgen_stroke::remove_all()
{
m_src_vertices.remove_all();
m_closed = 0;
m_status = initial;
}
void vcgen_stroke::add_vertex(float x, float y, unsigned cmd)
{
m_status = initial;
if(is_move_to(cmd)) {
m_src_vertices.modify_last(vertex_dist_cmd(x, y, cmd));
} else {
if(is_vertex(cmd)) {
m_src_vertices.add(vertex_dist_cmd(x, y, cmd));
} else {
m_closed = get_close_flag(cmd);
}
}
}
static inline void calc_butt_cap(float* cap,
const vertex_dist& v0,
const vertex_dist& v1,
float len,
float width) {
float dx = (v1.y - v0.y) * width / len;
float dy = (v1.x - v0.x) * width / len;
cap[0] = v0.x - dx;
cap[1] = v0.y + dy;
cap[2] = v0.x + dx;
cap[3] = v0.y - dy;
}
void vcgen_stroke::rewind(unsigned)
{
if(m_status == initial) {
m_src_vertices.close(m_closed != 0);
if(m_src_vertices.size() < 3) {
m_closed = 0;
}
}
m_status = ready;
m_src_vertex = 0;
m_out_vertex = 0;
}
unsigned vcgen_stroke::vertex(float* x, float* y)
{
unsigned cmd = path_cmd_line_to;
line_join_e curj;
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 = m_closed ? outline1 : cap1;
cmd = path_cmd_move_to;
m_src_vertex = 0;
m_out_vertex = 0;
break;
case cap1:
stroke_calc_cap(m_out_vertices,
m_src_vertices[0],
m_src_vertices[1],
m_src_vertices[0].dist,
m_line_cap,
m_width,
m_approx_scale);
m_src_vertex = 1;
m_prev_status = outline1;
m_status = out_vertices;
m_out_vertex = 0;
break;
case cap2:
stroke_calc_cap(m_out_vertices,
m_src_vertices[m_src_vertices.size() - 1],
m_src_vertices[m_src_vertices.size() - 2],
m_src_vertices[m_src_vertices.size() - 2].dist,
m_line_cap,
m_width,
m_approx_scale);
m_prev_status = outline2;
m_status = out_vertices;
m_out_vertex = 0;
break;
case outline1:
if(m_closed) {
if(m_src_vertex >= m_src_vertices.size()) {
m_prev_status = close_first;
m_status = end_poly1;
break;
}
} else {
if(m_src_vertex >= m_src_vertices.size() - 1) {
m_status = cap2;
break;
}
}
curj = m_src_vertices[m_src_vertex].cmd & path_flags_jr ? miter_join_round : m_line_join;
stroke_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_width,
curj,
m_inner_join,
m_miter_limit,
m_inner_miter_limit,
m_approx_scale);
++m_src_vertex;
m_prev_status = m_status;
m_status = out_vertices;
m_out_vertex = 0;
break;
case close_first:
m_status = outline2;
cmd = path_cmd_move_to;
case outline2:
if(m_src_vertex <= unsigned(m_closed == 0)) {
m_status = end_poly2;
m_prev_status = stop;
break;
}
--m_src_vertex;
curj = m_src_vertices[m_src_vertex].cmd & path_flags_jr ? miter_join_round : m_line_join;
stroke_calc_join(m_out_vertices,
m_src_vertices.next(m_src_vertex),
m_src_vertices.curr(m_src_vertex),
m_src_vertices.prev(m_src_vertex),
m_src_vertices.curr(m_src_vertex).dist,
m_src_vertices.prev(m_src_vertex).dist,
m_width,
curj,
m_inner_join,
m_miter_limit,
m_inner_miter_limit,
m_approx_scale);
m_prev_status = m_status;
m_status = out_vertices;
m_out_vertex = 0;
break;
case out_vertices:
if(m_out_vertex >= m_out_vertices.size()) {
m_status = m_prev_status;
} else {
const point_type& c = m_out_vertices[m_out_vertex++];
*x = c.x;
*y = c.y;
return cmd;
}
break;
case end_poly1:
m_status = m_prev_status;
return path_cmd_end_poly | path_flags_close | path_flags_ccw;
case end_poly2:
m_status = m_prev_status;
return path_cmd_end_poly | path_flags_close | path_flags_cw;
case stop:
cmd = path_cmd_stop;
break;
}
}
return cmd;
}
}