Blame view

ios/cocos2d/external/poly2tri/common/utils.h 3.5 KB
520389e3   xiaoyu   接入cocos源码,编译未通过,继续修改
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
  /*
   * Poly2Tri Copyright (c) 2009-2010, Poly2Tri Contributors
   * http://code.google.com/p/poly2tri/
   *
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without modification,
   * are permitted provided that the following conditions are met:
   *
   * * Redistributions of source code must retain the above copyright notice,
   *   this list of conditions and the following disclaimer.
   * * Redistributions in binary form must reproduce the above copyright notice,
   *   this list of conditions and the following disclaimer in the documentation
   *   and/or other materials provided with the distribution.
   * * Neither the name of Poly2Tri nor the names of its contributors may be
   *   used to endorse or promote products derived from this software without specific
   *   prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
   * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
   * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
   * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  #ifndef UTILS_H
  #define UTILS_H
  
  // Otherwise #defines like M_PI are undeclared under Visual Studio
  #define _USE_MATH_DEFINES
  
  #include <exception>
  #include <math.h>
  
  // C99 removes M_PI from math.h
  #ifndef M_PI
  #define M_PI 3.14159265358979323846264338327
  #endif
  
  namespace p2t {
  
  const double PI_3div4 = 3 * M_PI / 4;
  const double PI_div2 = 1.57079632679489661923;
  const double EPSILON = 1e-12;
  
  enum Orientation { CW, CCW, COLLINEAR };
  
  /**
   * Forumla to calculate signed area<br>
   * Positive if CCW<br>
   * Negative if CW<br>
   * 0 if collinear<br>
   * <pre>
   * A[P1,P2,P3]  =  (x1*y2 - y1*x2) + (x2*y3 - y2*x3) + (x3*y1 - y3*x1)
   *              =  (x1-x3)*(y2-y3) - (y1-y3)*(x2-x3)
   * </pre>
   */
  Orientation Orient2d(const Point& pa, const Point& pb, const Point& pc)
  {
    double detleft = (pa.x - pc.x) * (pb.y - pc.y);
    double detright = (pa.y - pc.y) * (pb.x - pc.x);
    double val = detleft - detright;
    if (val > -EPSILON && val < EPSILON) {
      return COLLINEAR;
    } else if (val > 0) {
      return CCW;
    }
    return CW;
  }
  
  /*
  bool InScanArea(Point& pa, Point& pb, Point& pc, Point& pd)
  {
    double pdx = pd.x;
    double pdy = pd.y;
    double adx = pa.x - pdx;
    double ady = pa.y - pdy;
    double bdx = pb.x - pdx;
    double bdy = pb.y - pdy;
  
    double adxbdy = adx * bdy;
    double bdxady = bdx * ady;
    double oabd = adxbdy - bdxady;
  
    if (oabd <= EPSILON) {
      return false;
    }
  
    double cdx = pc.x - pdx;
    double cdy = pc.y - pdy;
  
    double cdxady = cdx * ady;
    double adxcdy = adx * cdy;
    double ocad = cdxady - adxcdy;
  
    if (ocad <= EPSILON) {
      return false;
    }
  
    return true;
  }
  
  */
  
  bool InScanArea(const Point& pa, const Point& pb, const Point& pc, const Point& pd)
  {
    double oadb = (pa.x - pb.x)*(pd.y - pb.y) - (pd.x - pb.x)*(pa.y - pb.y);
    if (oadb >= -EPSILON) {
      return false;
    }
  
    double oadc = (pa.x - pc.x)*(pd.y - pc.y) - (pd.x - pc.x)*(pa.y - pc.y);
    if (oadc <= EPSILON) {
      return false;
    }
    return true;
  }
  
  }
  
  #endif