Home | History | Annotate | Download | only in agg23
      1 
      2 //----------------------------------------------------------------------------
      3 // Anti-Grain Geometry - Version 2.3
      4 // Copyright (C) 2002-2005 Maxim Shemanarev (http://www.antigrain.com)
      5 //
      6 // Permission to copy, use, modify, sell and distribute this software
      7 // is granted provided this copyright notice appears in all copies.
      8 // This software is provided "as is" without express or implied
      9 // warranty, and with no claim as to its suitability for any purpose.
     10 //
     11 //----------------------------------------------------------------------------
     12 // Contact: mcseem (at) antigrain.com
     13 //          mcseemagg (at) yahoo.com
     14 //          http://www.antigrain.com
     15 //----------------------------------------------------------------------------
     16 //
     17 // Line dash generator
     18 //
     19 //----------------------------------------------------------------------------
     20 
     21 #include "agg_shorten_path.h"
     22 #include "agg_vcgen_dash.h"
     23 #include "core/include/fxcrt/fx_basic.h"
     24 
     25 namespace agg
     26 {
     27 vcgen_dash::vcgen_dash() :
     28     m_total_dash_len(0),
     29     m_num_dashes(0),
     30     m_dash_start(0),
     31     m_shorten(0),
     32     m_curr_dash_start(0),
     33     m_curr_dash(0),
     34     m_src_vertices(),
     35     m_closed(0),
     36     m_status(initial),
     37     m_src_vertex(0)
     38 {
     39 }
     40 void vcgen_dash::remove_all_dashes()
     41 {
     42     m_total_dash_len = 0;
     43     m_num_dashes = 0;
     44     m_curr_dash_start = 0;
     45     m_curr_dash = 0;
     46 }
     47 void vcgen_dash::add_dash(FX_FLOAT dash_len, FX_FLOAT gap_len)
     48 {
     49     if(m_num_dashes < max_dashes) {
     50         m_total_dash_len += dash_len + gap_len;
     51         m_dashes[m_num_dashes++] = dash_len;
     52         m_dashes[m_num_dashes++] = gap_len;
     53     }
     54 }
     55 void vcgen_dash::dash_start(FX_FLOAT ds)
     56 {
     57     m_dash_start = ds;
     58     calc_dash_start(FXSYS_fabs(ds));
     59 }
     60 void vcgen_dash::calc_dash_start(FX_FLOAT ds)
     61 {
     62     m_curr_dash = 0;
     63     m_curr_dash_start = 0;
     64     while(ds > 0) {
     65         if(ds > m_dashes[m_curr_dash]) {
     66             ds -= m_dashes[m_curr_dash];
     67             ++m_curr_dash;
     68             m_curr_dash_start = 0;
     69             if(m_curr_dash >= m_num_dashes) {
     70                 m_curr_dash = 0;
     71             }
     72         } else {
     73             m_curr_dash_start = ds;
     74             ds = 0;
     75         }
     76     }
     77 }
     78 void vcgen_dash::remove_all()
     79 {
     80     m_status = initial;
     81     m_src_vertices.remove_all();
     82     m_closed = 0;
     83 }
     84 void vcgen_dash::add_vertex(FX_FLOAT x, FX_FLOAT y, unsigned cmd)
     85 {
     86     m_status = initial;
     87     if(is_move_to(cmd)) {
     88         m_src_vertices.modify_last(vertex_dist(x, y));
     89     } else {
     90         if(is_vertex(cmd)) {
     91             m_src_vertices.add(vertex_dist(x, y));
     92         } else {
     93             m_closed = get_close_flag(cmd);
     94         }
     95     }
     96 }
     97 void vcgen_dash::rewind(unsigned)
     98 {
     99     if(m_status == initial) {
    100         m_src_vertices.close(m_closed != 0);
    101         shorten_path(m_src_vertices, m_shorten, m_closed);
    102     }
    103     m_status = ready;
    104     m_src_vertex = 0;
    105 }
    106 unsigned vcgen_dash::vertex(FX_FLOAT* x, FX_FLOAT* y)
    107 {
    108     unsigned cmd = path_cmd_move_to;
    109     while(!is_stop(cmd)) {
    110         switch(m_status) {
    111             case initial:
    112                 rewind(0);
    113             case ready:
    114                 if(m_num_dashes < 2 || m_src_vertices.size() < 2) {
    115                     cmd = path_cmd_stop;
    116                     break;
    117                 }
    118                 m_status = polyline;
    119                 m_src_vertex = 1;
    120                 m_v1 = &m_src_vertices[0];
    121                 m_v2 = &m_src_vertices[1];
    122                 m_curr_rest = m_v1->dist;
    123                 *x = m_v1->x;
    124                 *y = m_v1->y;
    125                 if(m_dash_start >= 0) {
    126                     calc_dash_start(m_dash_start);
    127                 }
    128                 return path_cmd_move_to;
    129             case polyline: {
    130                     FX_FLOAT dash_rest = m_dashes[m_curr_dash] - m_curr_dash_start;
    131                     unsigned cmd = (m_curr_dash & 1) ?
    132                                    path_cmd_move_to :
    133                                    path_cmd_line_to;
    134                     if(m_curr_rest > dash_rest) {
    135                         m_curr_rest -= dash_rest;
    136                         ++m_curr_dash;
    137                         if(m_curr_dash >= m_num_dashes) {
    138                             m_curr_dash = 0;
    139                         }
    140                         m_curr_dash_start = 0;
    141                         *x = m_v2->x - (m_v2->x - m_v1->x) * m_curr_rest / m_v1->dist;
    142                         *y = m_v2->y - (m_v2->y - m_v1->y) * m_curr_rest / m_v1->dist;
    143                     } else {
    144                         m_curr_dash_start += m_curr_rest;
    145                         *x = m_v2->x;
    146                         *y = m_v2->y;
    147                         ++m_src_vertex;
    148                         m_v1 = m_v2;
    149                         m_curr_rest = m_v1->dist;
    150                         if(m_closed) {
    151                             if(m_src_vertex > m_src_vertices.size()) {
    152                                 m_status = stop;
    153                             } else {
    154                                 m_v2 = &m_src_vertices
    155                                        [
    156                                            (m_src_vertex >= m_src_vertices.size()) ? 0 :
    157                                            m_src_vertex
    158                                        ];
    159                             }
    160                         } else {
    161                             if(m_src_vertex >= m_src_vertices.size()) {
    162                                 m_status = stop;
    163                             } else {
    164                                 m_v2 = &m_src_vertices[m_src_vertex];
    165                             }
    166                         }
    167                     }
    168                     return cmd;
    169                 }
    170                 break;
    171             case stop:
    172                 cmd = path_cmd_stop;
    173                 break;
    174         }
    175     }
    176     return path_cmd_stop;
    177 }
    178 }
    179