agg/inc/agg_conv_adaptor_vcgen.h

   1 //----------------------------------------------------------------------------
   2 // Anti-Grain Geometry - Version 2.3
   3 // Copyright (C) 2002-2005 Maxim Shemanarev (http://www.antigrain.com)
   4 //
   5 // Permission to copy, use, modify, sell and distribute this software
   6 // is granted provided this copyright notice appears in all copies.
   7 // This software is provided "as is" without express or implied
   8 // warranty, and with no claim as to its suitability for any purpose.
   9 //
  10 //----------------------------------------------------------------------------
  11 // Contact: mcseem@antigrain.com
  12 //          mcseemagg@yahoo.com
  13 //          http://www.antigrain.com
  14 //----------------------------------------------------------------------------
  15
  16 #ifndef AGG_CONV_ADAPTOR_VCGEN_INCLUDED
  17 #define AGG_CONV_ADAPTOR_VCGEN_INCLUDED
  18
  19 #include "agg_basics.h"
  20 #include "agg_vertex_iterator.h"
  21
  22 namespace agg
  23 {
  24     //------------------------------------------------------------null_markers
  25     struct null_markers
  26     {
  27         void remove_all() {}
  28         void add_vertex(double, double, unsigned) {}
  29         void prepare_src() {}
  30
  31         void rewind(unsigned) {}
  32         unsigned vertex(double*, double*) { return path_cmd_stop; }
  33
  34         typedef null_markers source_type;
  35         typedef vertex_iterator<source_type> iterator;
  36         iterator begin(unsigned id) { return iterator(*this, id); }
  37         iterator end() { return iterator(path_cmd_stop); }
  38     };
  39
  40
  41     //------------------------------------------------------conv_adaptor_vcgen
  42     template<class VertexSource,
  43              class Generator,
  44              class Markers=null_markers> class conv_adaptor_vcgen
  45     {
  46         enum status
  47         {
  48             initial,
  49             accumulate,
  50             generate
  51         };
  52
  53     public:
  54         conv_adaptor_vcgen(VertexSource& source) :
  55             m_source(&source),
  56             m_status(initial)
  57         {}
  58
  59         void set_source(VertexSource& source) { m_source = &source; }
  60
  61         Generator& generator() { return m_generator; }
  62         const Generator& generator() const { return m_generator; }
  63
  64         Markers& markers() { return m_markers; }
  65         const Markers& markers() const { return m_markers; }
  66
  67         void rewind(unsigned id)
  68         {
  69             m_source->rewind(id);
  70             m_status = initial;
  71         }
  72
  73         unsigned vertex(double* x, double* y);
  74
  75         typedef conv_adaptor_vcgen<VertexSource, Generator, Markers> source_type;
  76         typedef vertex_iterator<source_type> iterator;
  77         iterator begin(unsigned id) { return iterator(*this, id); }
  78         iterator end() { return iterator(path_cmd_stop); }
  79
  80     private:
  81         // Prohibit copying
  82         conv_adaptor_vcgen(const conv_adaptor_vcgen<VertexSource, Generator, Markers>&);
  83         const conv_adaptor_vcgen<VertexSource, Generator, Markers>&
  84             operator = (const conv_adaptor_vcgen<VertexSource, Generator, Markers>&);
  85
  86         VertexSource* m_source;
  87         Generator     m_generator;
  88         Markers       m_markers;
  89         status        m_status;
  90         unsigned      m_last_cmd;
  91         double        m_start_x;
  92         double        m_start_y;
  93     };
  94
  95
  96
  97
  98
  99     //------------------------------------------------------------------------
 100     template<class VertexSource, class Generator, class Markers>
 101     unsigned conv_adaptor_vcgen<VertexSource, Generator, Markers>::vertex(double* x, double* y)
 102     {
 103         unsigned cmd = path_cmd_stop;
 104         bool done = false;
 105         while(!done)
 106         {
 107             switch(m_status)
 108             {
 109             case initial:
 110                 m_markers.remove_all();
 111                 m_last_cmd = m_source->vertex(&m_start_x, &m_start_y);
 112                 m_status = accumulate;
 113
 114             case accumulate:
 115                 if(is_stop(m_last_cmd)) return path_cmd_stop;
 116
 117                 m_generator.remove_all();
 118                 m_generator.add_vertex(m_start_x, m_start_y, path_cmd_move_to);
 119                 m_markers.add_vertex(m_start_x, m_start_y, path_cmd_move_to);
 120
 121                 for(;;)
 122                 {
 123                     cmd = m_source->vertex(x, y);
 124                     if(is_vertex(cmd))
 125                     {
 126                         m_last_cmd = cmd;
 127                         if(is_move_to(cmd))
 128                         {
 129                             m_start_x = *x;
 130                             m_start_y = *y;
 131                             break;
 132                         }
 133                         m_generator.add_vertex(*x, *y, cmd);
 134                         m_markers.add_vertex(*x, *y, path_cmd_line_to);
 135                     }
 136                     else
 137                     {
 138                         if(is_stop(cmd))
 139                         {
 140                             m_last_cmd = path_cmd_stop;
 141                             break;
 142                         }
 143                         if(is_end_poly(cmd))
 144                         {
 145                             m_generator.add_vertex(*x, *y, cmd);
 146                             break;
 147                         }
 148                     }
 149                 }
 150                 m_generator.rewind(0);
 151                 m_status = generate;
 152
 153             case generate:
 154                 cmd = m_generator.vertex(x, y);
 155                 if(is_stop(cmd))
 156                 {
 157                     m_status = accumulate;
 158                     break;
 159                 }
 160                 done = true;
 161                 break;
 162             }
 163         }
 164         return cmd;
 165     }
 166
 167 }
 168
 169 #endif