ReactOS  0.4.14-dev-1276-g8aa58c1
knotvector.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  * knotvector.c++
37  *
38  */
39 
40 //#include "glimports.h"
41 //#include "mystdio.h"
42 #include "myassert.h"
43 #include "knotvector.h"
44 #include "defines.h"
45 
46 #ifdef __WATCOMC__
47 #pragma warning 726 10
48 #endif
49 
50 void Knotvector::init( long _knotcount, long _stride, long _order, INREAL *_knotlist )
51 {
52  knotcount = _knotcount;
53  stride = _stride;
54  order = _order;
55  knotlist = new Knot[_knotcount];
56  assert( knotlist != 0 );
57 
58  for( int i = 0; i != _knotcount; i++ )
59  knotlist[i] = (Knot) _knotlist[i];
60 }
61 
63 {
64  knotcount = 0;
65  stride = 0;
66  order = 0;
67  knotlist = 0;
68 }
69 
71 {
72  if( knotlist ) delete[] knotlist;
73 }
74 
76 {
77  /* kindex is used as an array index so subtract one first,
78  * this propagates throughout the code so study carefully */
79  long kindex = knotcount-1;
80 
82  // spline order un-supported
83  return( 1 );
84  }
85 
86  if( knotcount < (2 * order) ) {
87  // too few knots
88  return( 2 );
89  }
90 
91  if( identical( knotlist[kindex-(order-1)], knotlist[order-1]) ) {
92  // valid knot range is empty
93  return( 3 );
94  }
95 
96  for( long i = 0; i < kindex; i++)
97  if( knotlist[i] > knotlist[i+1] ) {
98  // decreasing knot sequence
99  return( 4 );
100  }
101 
102  /* check for valid multiplicity */
103 
104  /* kindex is currently the index of the last knot.
105  * In the next loop it is decremented to ignore the last knot
106  * and the loop stops when kindex is 2 so as to ignore the first
107  * knot as well. These knots are not used in computing
108  * knot multiplicities.
109  */
110 
111  long multi = 1;
112  for( ; kindex >= 1; kindex-- ) {
113  if( knotlist[kindex] - knotlist[kindex-1] < TOLERANCE ) {
114  multi++;
115  continue;
116  }
117  if ( multi > order ) {
118  // knot multiplicity greater than order of spline
119  return( 5 );
120  }
121  multi = 1;
122  }
123 
124  if ( multi > order ) {
125  // knot multiplicity greater than order of spline
126  return( 5 );
127  }
128 
129  return 0;
130 }
131 
132 void Knotvector::show( const char *msg )
133 {
134 #ifndef NDEBUG
135  _glu_dprintf( "%s\n", msg );
136  _glu_dprintf( "order = %ld, count = %ld\n", order, knotcount );
137 
138  for( int i=0; i<knotcount; i++ )
139  _glu_dprintf( "knot[%d] = %g\n", i, knotlist[i] );
140 #endif
141 }
142 
GLuint GLdouble GLdouble GLint GLint order
Definition: glext.h:11194
void init(long, long, long, INREAL *)
Definition: knotvector.cc:50
Knot * knotlist
Definition: knotvector.h:51
REAL Knot
Definition: types.h:45
#define assert(x)
Definition: debug.h:53
void show(const char *)
Definition: knotvector.cc:132
GLsizei GLenum const GLvoid GLsizei GLenum GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLint GLint GLint GLshort GLshort GLshort GLubyte GLubyte GLubyte GLuint GLuint GLuint GLushort GLushort GLushort GLbyte GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLfloat GLint GLint GLint GLint GLshort GLshort GLshort GLshort GLubyte GLubyte GLubyte GLubyte GLuint GLuint GLuint GLuint GLushort GLushort GLushort GLushort GLboolean const GLdouble const GLfloat const GLint const GLshort const GLbyte const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLdouble const GLfloat const GLfloat const GLint const GLint const GLshort const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort GLenum GLenum GLenum GLfloat GLenum GLint GLenum GLenum GLenum GLfloat GLenum GLenum GLint GLenum GLfloat GLenum GLint GLint GLushort GLenum GLenum GLfloat GLenum GLenum GLint GLfloat const GLubyte GLenum GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLint GLint GLsizei GLsizei GLint GLenum GLenum const GLvoid GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLenum const GLdouble GLenum GLenum const GLfloat GLenum GLenum const GLint GLsizei GLuint GLfloat GLuint GLbitfield GLfloat GLint GLuint GLboolean GLenum GLfloat GLenum GLbitfield GLenum GLfloat GLfloat GLint GLint const GLfloat GLenum GLfloat GLfloat GLint GLint GLfloat GLfloat GLint GLint const GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat const GLdouble const GLfloat const GLdouble const GLfloat GLint i
Definition: glfuncs.h:248
#define MAXORDER
Definition: defines.h:45
GLsizei stride
Definition: glext.h:5848
#define INREAL
Definition: types.h:40
int identical(Knot x, Knot y)
Definition: knotvector.h:58
~Knotvector(void)
Definition: knotvector.cc:70
#define TOLERANCE
Definition: bezierEval.cc:48
long knotcount
Definition: knotvector.h:49
#define msg(x)
Definition: auth_time.c:54
int validate(void)
Definition: knotvector.cc:75
Knotvector(void)
Definition: knotvector.cc:62