agg/source/agg_rounded_rect.cpp

   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 // Rounded rectangle vertex generator
  17 //
  18 //----------------------------------------------------------------------------
  19
  20 #include <math.h>
  21 #include "agg_rounded_rect.h"
  22
  23
  24 namespace agg
  25 {
  26     //------------------------------------------------------------------------
  27     rounded_rect::rounded_rect(double x1, double y1, double x2, double y2, double r) :
  28         m_x1(x1), m_y1(y1), m_x2(x2), m_y2(y2),
  29         m_rx1(r), m_ry1(r), m_rx2(r), m_ry2(r),
  30         m_rx3(r), m_ry3(r), m_rx4(r), m_ry4(r)
  31     {
  32         if(x1 > x2) { m_x1 = x2; m_x2 = x1; }
  33         if(y1 > y2) { m_y1 = y2; m_y2 = y1; }
  34     }
  35
  36     //--------------------------------------------------------------------
  37     void rounded_rect::rect(double x1, double y1, double x2, double y2)
  38     {
  39         m_x1 = x1;
  40         m_y1 = y1;
  41         m_x2 = x2;
  42         m_y2 = y2;
  43         if(x1 > x2) { m_x1 = x2; m_x2 = x1; }
  44         if(y1 > y2) { m_y1 = y2; m_y2 = y1; }
  45     }
  46
  47     //--------------------------------------------------------------------
  48     void rounded_rect::radius(double r)
  49     {
  50         m_rx1 = m_ry1 = m_rx2 = m_ry2 = m_rx3 = m_ry3 = m_rx4 = m_ry4 = r;
  51     }
  52
  53     //--------------------------------------------------------------------
  54     void rounded_rect::radius(double rx, double ry)
  55     {
  56         m_rx1 = m_rx2 = m_rx3 = m_rx4 = rx;
  57         m_ry1 = m_ry2 = m_ry3 = m_ry4 = ry;
  58     }
  59
  60     //--------------------------------------------------------------------
  61     void rounded_rect::radius(double rx_bottom, double ry_bottom,
  62                               double rx_top,    double ry_top)
  63     {
  64         m_rx1 = m_rx2 = rx_bottom;
  65         m_rx3 = m_rx4 = rx_top;
  66         m_ry1 = m_ry2 = ry_bottom;
  67         m_ry3 = m_ry4 = ry_top;
  68     }
  69
  70     //--------------------------------------------------------------------
  71     void rounded_rect::radius(double rx1, double ry1, double rx2, double ry2,
  72                               double rx3, double ry3, double rx4, double ry4)
  73     {
  74         m_rx1 = rx1; m_ry1 = ry1; m_rx2 = rx2; m_ry2 = ry2;
  75         m_rx3 = rx3; m_ry3 = ry3; m_rx4 = rx4; m_ry4 = ry4;
  76     }
  77
  78     //--------------------------------------------------------------------
  79     void rounded_rect::normalize_radius()
  80     {
  81         double dx = fabs(m_y2 - m_y1);
  82         double dy = fabs(m_x2 - m_x1);
  83
  84         double k = 1.0;
  85         double t;
  86         t = dx / (m_rx1 + m_rx2); if(t < k) k = t;
  87         t = dx / (m_rx3 + m_rx4); if(t < k) k = t;
  88         t = dy / (m_ry1 + m_ry2); if(t < k) k = t;
  89         t = dy / (m_ry3 + m_ry4); if(t < k) k = t;
  90
  91         if(k < 1.0)
  92         {
  93             m_rx1 *= k; m_ry1 *= k; m_rx2 *= k; m_ry2 *= k;
  94             m_rx3 *= k; m_ry3 *= k; m_rx4 *= k; m_ry4 *= k;
  95         }
  96     }
  97
  98     //--------------------------------------------------------------------
  99     void rounded_rect::rewind(unsigned)
 100     {
 101         m_status = 0;
 102     }
 103
 104     //--------------------------------------------------------------------
 105     unsigned rounded_rect::vertex(double* x, double* y)
 106     {
 107         unsigned cmd = path_cmd_stop;
 108         switch(m_status)
 109         {
 110         case 0:
 111             m_arc.init(m_x1 + m_rx1, m_y1 + m_ry1, m_rx1, m_ry1,
 112                        pi, pi+pi*0.5);
 113             m_arc.rewind(0);
 114             m_status++;
 115
 116         case 1:
 117             cmd = m_arc.vertex(x, y);
 118             if(is_stop(cmd)) m_status++;
 119             else return cmd;
 120
 121         case 2:
 122             m_arc.init(m_x2 - m_rx2, m_y1 + m_ry2, m_rx2, m_ry2,
 123                        pi+pi*0.5, 0.0);
 124             m_arc.rewind(0);
 125             m_status++;
 126
 127         case 3:
 128             cmd = m_arc.vertex(x, y);
 129             if(is_stop(cmd)) m_status++;
 130             else return path_cmd_line_to;
 131
 132         case 4:
 133             m_arc.init(m_x2 - m_rx3, m_y2 - m_ry3, m_rx3, m_ry3,
 134                        0.0, pi*0.5);
 135             m_arc.rewind(0);
 136             m_status++;
 137
 138         case 5:
 139             cmd = m_arc.vertex(x, y);
 140             if(is_stop(cmd)) m_status++;
 141             else return path_cmd_line_to;
 142
 143         case 6:
 144             m_arc.init(m_x1 + m_rx4, m_y2 - m_ry4, m_rx4, m_ry4,
 145                        pi*0.5, pi);
 146             m_arc.rewind(0);
 147             m_status++;
 148
 149         case 7:
 150             cmd = m_arc.vertex(x, y);
 151             if(is_stop(cmd)) m_status++;
 152             else return path_cmd_line_to;
 153
 154         case 8:
 155             cmd = (unsigned)path_cmd_end_poly | (unsigned)path_flags_close | (unsigned)path_flags_ccw;
 156             m_status++;
 157             break;
 158         }
 159         return cmd;
 160     }
 161
 162
 163 }
 164