1
2 //----------------------------------------------------------------------------
3 // XYQ: 2006-01-22 Copied from AGG project.
4 // TODO: This file uses intensive floating point operations, so it's NOT suitable
5 // for platforms like Symbian OS. We need to change to FIX format.
6 //----------------------------------------------------------------------------
7 //----------------------------------------------------------------------------
8 // Anti-Grain Geometry - Version 2.3
9 // Copyright (C) 2002-2005 Maxim Shemanarev (http://www.antigrain.com)
10 //
11 // Permission to copy, use, modify, sell and distribute this software
12 // is granted provided this copyright notice appears in all copies.
13 // This software is provided "as is" without express or implied
14 // warranty, and with no claim as to its suitability for any purpose.
15 //
16 //----------------------------------------------------------------------------
17 // Contact: mcseem@antigrain.com
18 // mcseemagg@yahoo.com
19 // http://www.antigrain.com
20 //----------------------------------------------------------------------------
21
22 #include "agg_curves.h"
23 #include "agg_math.h"
24 #include "core/fxcrt/fx_basic.h"
25
26 namespace agg
27 {
28 const FX_FLOAT curve_collinearity_epsilon = 1e-30f;
29 enum curve_recursion_limit_e { curve_recursion_limit = 16 };
init(FX_FLOAT x1,FX_FLOAT y1,FX_FLOAT x2,FX_FLOAT y2,FX_FLOAT x3,FX_FLOAT y3,FX_FLOAT x4,FX_FLOAT y4)30 void curve4_div::init(FX_FLOAT x1, FX_FLOAT y1,
31 FX_FLOAT x2, FX_FLOAT y2,
32 FX_FLOAT x3, FX_FLOAT y3,
33 FX_FLOAT x4, FX_FLOAT y4)
34 {
35 m_points.remove_all();
36 m_distance_tolerance_square = 1.0f / 4;
37 m_distance_tolerance_manhattan = 1.0f * 4;
38 bezier(x1, y1, x2, y2, x3, y3, x4, y4);
39 m_count = 0;
40 }
recursive_bezier(FX_FLOAT x1,FX_FLOAT y1,FX_FLOAT x2,FX_FLOAT y2,FX_FLOAT x3,FX_FLOAT y3,FX_FLOAT x4,FX_FLOAT y4,unsigned level)41 void curve4_div::recursive_bezier(FX_FLOAT x1, FX_FLOAT y1,
42 FX_FLOAT x2, FX_FLOAT y2,
43 FX_FLOAT x3, FX_FLOAT y3,
44 FX_FLOAT x4, FX_FLOAT y4,
45 unsigned level)
46 {
47 if(level > curve_recursion_limit) {
48 return;
49 }
50 FX_FLOAT x12 = (x1 + x2) / 2;
51 FX_FLOAT y12 = (y1 + y2) / 2;
52 FX_FLOAT x23 = (x2 + x3) / 2;
53 FX_FLOAT y23 = (y2 + y3) / 2;
54 FX_FLOAT x34 = (x3 + x4) / 2;
55 FX_FLOAT y34 = (y3 + y4) / 2;
56 FX_FLOAT x123 = (x12 + x23) / 2;
57 FX_FLOAT y123 = (y12 + y23) / 2;
58 FX_FLOAT x234 = (x23 + x34) / 2;
59 FX_FLOAT y234 = (y23 + y34) / 2;
60 FX_FLOAT x1234 = (x123 + x234) / 2;
61 FX_FLOAT y1234 = (y123 + y234) / 2;
62 FX_FLOAT dx = x4 - x1;
63 FX_FLOAT dy = y4 - y1;
64 FX_FLOAT d2 = FXSYS_fabs(((x2 - x4) * dy) - ((y2 - y4) * dx));
65 FX_FLOAT d3 = FXSYS_fabs(((x3 - x4) * dy) - ((y3 - y4) * dx));
66 switch((int(d2 > curve_collinearity_epsilon) << 1) +
67 int(d3 > curve_collinearity_epsilon)) {
68 case 0:
69 if(FXSYS_fabs(x1 + x3 - x2 - x2) +
70 FXSYS_fabs(y1 + y3 - y2 - y2) +
71 FXSYS_fabs(x2 + x4 - x3 - x3) +
72 FXSYS_fabs(y2 + y4 - y3 - y3) <= m_distance_tolerance_manhattan) {
73 m_points.add(point_type(x1234, y1234, path_flags_jr));
74 return;
75 }
76 break;
77 case 1:
78 if ((d3 * d3) <=
79 (m_distance_tolerance_square * ((dx * dx) + (dy * dy)))) {
80 m_points.add(point_type(x23, y23, path_flags_jr));
81 return;
82 }
83 break;
84 case 2:
85 if ((d2 * d2) <=
86 (m_distance_tolerance_square * ((dx * dx) + (dy * dy)))) {
87 m_points.add(point_type(x23, y23, path_flags_jr));
88 return;
89 }
90 break;
91 case 3:
92 if (((d2 + d3) * (d2 + d3)) <=
93 (m_distance_tolerance_square * ((dx * dx) + (dy * dy)))) {
94 m_points.add(point_type(x23, y23, path_flags_jr));
95 return;
96 }
97 break;
98 }
99 recursive_bezier(x1, y1, x12, y12, x123, y123, x1234, y1234, level + 1);
100 recursive_bezier(x1234, y1234, x234, y234, x34, y34, x4, y4, level + 1);
101 }
bezier(FX_FLOAT x1,FX_FLOAT y1,FX_FLOAT x2,FX_FLOAT y2,FX_FLOAT x3,FX_FLOAT y3,FX_FLOAT x4,FX_FLOAT y4)102 void curve4_div::bezier(FX_FLOAT x1, FX_FLOAT y1,
103 FX_FLOAT x2, FX_FLOAT y2,
104 FX_FLOAT x3, FX_FLOAT y3,
105 FX_FLOAT x4, FX_FLOAT y4)
106 {
107 m_points.add(point_type(x1, y1));
108 recursive_bezier(x1, y1, x2, y2, x3, y3, x4, y4, 0);
109 m_points.add(point_type(x4, y4));
110 }
111 }
112