headers/libs/agg/agg_bounding_rect.h

   1 //----------------------------------------------------------------------------
   2 // Anti-Grain Geometry - Version 2.4
   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 // bounding_rect function template
  17 //
  18 //----------------------------------------------------------------------------
  19 #ifndef AGG_BOUNDING_RECT_INCLUDED
  20 #define AGG_BOUNDING_RECT_INCLUDED
  21
  22 #include "agg_basics.h"
  23
  24 namespace agg
  25 {
  26
  27     //-----------------------------------------------------------bounding_rect
  28     template<class VertexSource, class GetId, class CoordT>
  29     bool bounding_rect(VertexSource& vs, GetId& gi,
  30                        unsigned start, unsigned num,
  31                        CoordT* x1, CoordT* y1, CoordT* x2, CoordT* y2)
  32     {
  33         unsigned i;
  34         double x;
  35         double y;
  36         bool first = true;
  37
  38         *x1 = CoordT(1);
  39         *y1 = CoordT(1);
  40         *x2 = CoordT(0);
  41         *y2 = CoordT(0);
  42
  43         for(i = 0; i < num; i++)
  44         {
  45             vs.rewind(gi[start + i]);
  46             unsigned cmd;
  47             while(!is_stop(cmd = vs.vertex(&x, &y)))
  48             {
  49                 if(is_vertex(cmd))
  50                 {
  51                     if(first)
  52                     {
  53                         *x1 = CoordT(x);
  54                         *y1 = CoordT(y);
  55                         *x2 = CoordT(x);
  56                         *y2 = CoordT(y);
  57                         first = false;
  58                     }
  59                     else
  60                     {
  61                         if(CoordT(x) < *x1) *x1 = CoordT(x);
  62                         if(CoordT(y) < *y1) *y1 = CoordT(y);
  63                         if(CoordT(x) > *x2) *x2 = CoordT(x);
  64                         if(CoordT(y) > *y2) *y2 = CoordT(y);
  65                     }
  66                 }
  67             }
  68         }
  69         return *x1 <= *x2 && *y1 <= *y2;
  70     }
  71
  72
  73     //-----------------------------------------------------bounding_rect_single
  74     template<class VertexSource, class CoordT>
  75     bool bounding_rect_single(VertexSource& vs, unsigned path_id,
  76                               CoordT* x1, CoordT* y1, CoordT* x2, CoordT* y2)
  77     {
  78         double x;
  79         double y;
  80         bool first = true;
  81
  82         *x1 = CoordT(1);
  83         *y1 = CoordT(1);
  84         *x2 = CoordT(0);
  85         *y2 = CoordT(0);
  86
  87         vs.rewind(path_id);
  88         unsigned cmd;
  89         while(!is_stop(cmd = vs.vertex(&x, &y)))
  90         {
  91             if(is_vertex(cmd))
  92             {
  93                 if(first)
  94                 {
  95                     *x1 = CoordT(x);
  96                     *y1 = CoordT(y);
  97                     *x2 = CoordT(x);
  98                     *y2 = CoordT(y);
  99                     first = false;
 100                 }
 101                 else
 102                 {
 103                     if(CoordT(x) < *x1) *x1 = CoordT(x);
 104                     if(CoordT(y) < *y1) *y1 = CoordT(y);
 105                     if(CoordT(x) > *x2) *x2 = CoordT(x);
 106                     if(CoordT(y) > *y2) *y2 = CoordT(y);
 107                 }
 108             }
 109         }
 110         return *x1 <= *x2 && *y1 <= *y2;
 111     }
 112
 113
 114 }
 115
 116 #endif