Anti-Grain Geometry Tutorial
agg_rounded_rect.cpp
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 // Rounded rectangle vertex generator
17 //
18 //----------------------------------------------------------------------------
19 
20 #include <cmath>
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 = std::fabs(m_y2 - m_y1);
82  double dy = std::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 = path_cmd_end_poly | path_flags_close | path_flags_ccw;
156  m_status++;
157  break;
158  }
159  return cmd;
160  }
161 
162 
163 }
164 
agg
Definition: agg_arc.cpp:24