ReactOS  0.4.12-dev-90-g2e2e63e
partitionX.cc
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1 /*
2 ** License Applicability. Except to the extent portions of this file are
3 ** made subject to an alternative license as permitted in the SGI Free
4 ** Software License B, Version 1.1 (the "License"), the contents of this
5 ** file are subject only to the provisions of the License. You may not use
6 ** this file except in compliance with the License. You may obtain a copy
7 ** of the License at Silicon Graphics, Inc., attn: Legal Services, 1600
8 ** Amphitheatre Parkway, Mountain View, CA 94043-1351, or at:
9 **
10 ** http://oss.sgi.com/projects/FreeB
11 **
12 ** Note that, as provided in the License, the Software is distributed on an
13 ** "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS
14 ** DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND
15 ** CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A
16 ** PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
17 **
18 ** Original Code. The Original Code is: OpenGL Sample Implementation,
19 ** Version 1.2.1, released January 26, 2000, developed by Silicon Graphics,
20 ** Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc.
21 ** Copyright in any portions created by third parties is as indicated
22 ** elsewhere herein. All Rights Reserved.
23 **
24 ** Additional Notice Provisions: The application programming interfaces
25 ** established by SGI in conjunction with the Original Code are The
26 ** OpenGL(R) Graphics System: A Specification (Version 1.2.1), released
27 ** April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version
28 ** 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X
29 ** Window System(R) (Version 1.3), released October 19, 1998. This software
30 ** was created using the OpenGL(R) version 1.2.1 Sample Implementation
31 ** published by SGI, but has not been independently verified as being
32 ** compliant with the OpenGL(R) version 1.2.1 Specification.
33 **
34 */
35 /*
36 */
37 
38 #include <stdlib.h>
39 //#include <stdio.h>
40 
41 #include "partitionX.h"
42 
43 #define CONCAVITY_ZERO 1.0e-6 //this number is used to test whether a vertex is concave (refelx)
44  //or not. The test needs to compute the area of the three adjacent
45  //vertices to see if the are is positive or negative.
46 
48 {
49  //if v->prev <= v && v->next <= v
50  //|| v->prev >= v && v->next >= v
51  Real* T = v->head();
52  Real* P = v->getPrev()->head();
53  Real* N = v->getNext()->head();
54  if(
55  (compV2InX(T,P) != -1 &&
56  compV2InX(T,N) != -1
57  ) ||
58  (compV2InX(T,P) != 1 &&
59  compV2InX(T,N) != 1
60  )
61  )
62  return 1;
63  else
64  return 0;
65 }
66 
68 {
69  Real* A = v->getPrev()->head();
70  Real* B = v->head();
71  Real* C = v->tail();
72  Real Bx,By, Cx, Cy;
73  //scale them in case they are too small
74  Bx = 10*(B[0] - A[0]);
75  By = 10*(B[1] - A[1]);
76  Cx = 10*(C[0] - A[0]);
77  Cy = 10*(C[1] - A[1]);
78 
79  if(Bx*Cy - Cx*By < -CONCAVITY_ZERO) return 1;
80  else return 0;
81 }
82 
83 
84 /*return
85  *0: not-cusp
86  *1: interior cusp
87  *2: exterior cusp
88  */
90 {
91  if(! isCuspX(v)) return 0;
92  else
93  {
94 //printf("isCusp,%f,%f\n", v->head()[0], v->head()[1]);
95  if(isReflexX(v))
96  {
97 // printf("isReflex\n");
98  return 1;
99  }
100  else
101  {
102 // printf("not isReflex\n");
103  return 2;
104  }
105  }
106 }
107 
109 {
111  int ret = 0;
112  if(cuspTypeX(polygon) == 1)
113  ret++;
114  for(temp = polygon->getNext(); temp != polygon; temp = temp->getNext())
115  if(cuspTypeX(temp) == 1)
116  ret++;
117  return ret;
118 }
119 
120 
121 void findInteriorCuspsX(directedLine *polygon, Int& ret_n_interior_cusps,
122  directedLine** ret_interior_cusps)
123 {
125  ret_n_interior_cusps = 0;
126  if(cuspTypeX(polygon) == 1)
127  {
128  ret_interior_cusps[ret_n_interior_cusps++] = polygon;
129  }
130  for(temp = polygon->getNext(); temp != polygon; temp = temp->getNext())
131  if(cuspTypeX(temp) == 1)
132  {
133  ret_interior_cusps[ret_n_interior_cusps++] = temp;
134  }
135 }
136 
138 {
140  Int is_minimal = ((compV2InX(cusp->head(), cusp->tail()) == -1)? 1:0);
141 
142  if(is_minimal)
143  for(temp = cusp->getNext(); temp != cusp; temp = temp->getNext())
144  {
145  if(compV2InX(cusp->head(), temp->head()) == 1)
146  {
147  return temp;
148  }
149  }
150  else //is maxmal
151  for(temp = cusp->getNext(); temp != cusp; temp = temp->getNext())
152  {
153  if(compV2InX(cusp->head(), temp->head()) == -1)
154  {
155  return temp;
156  }
157  }
158  return NULL;
159 }
160 
161 
162 
Real * head()
Int isCuspX(directedLine *v)
Definition: partitionX.cc:47
#define B(row, col)
Definition: m_matrix.c:146
#define T
Definition: mbstring.h:31
directedLine * getPrev()
Definition: directedLine.h:73
directedLine * getNext()
Definition: directedLine.h:74
Definition: bidi.c:97
Int isReflexX(directedLine *v)
Definition: partitionX.cc:67
smooth NULL
Definition: ftsmooth.c:416
Int compV2InX(Real A[2], Real B[2])
void findInteriorCuspsX(directedLine *polygon, Int &ret_n_interior_cusps, directedLine **ret_interior_cusps)
Definition: partitionX.cc:121
Int numInteriorCuspsX(directedLine *polygon)
Definition: partitionX.cc:108
int ret
Definition: ttei1.cpp:12
static stack_node_t temp
Definition: rpn.c:18
Real * tail()
const GLdouble * v
Definition: gl.h:2040
Definition: ttei6.cpp:27
float Real
Definition: definitions.h:36
#define CONCAVITY_ZERO
Definition: partitionX.cc:43
Int cuspTypeX(directedLine *v)
Definition: partitionX.cc:89
directedLine * findDiagonal_singleCuspX(directedLine *cusp)
Definition: partitionX.cc:137
#define P(row, col)
Definition: m_matrix.c:147
int Int
Definition: definitions.h:37