ReactOS  0.4.13-dev-249-gcba1a2f
normal.c File Reference
#include "gluos.h"
#include "tess.h"
Include dependency graph for normal.c:

Go to the source code of this file.

Macros

#define TRUE   1
 
#define FALSE   0
 
#define Dot(u, v)   (u[0]*v[0] + u[1]*v[1] + u[2]*v[2])
 
#define ABS(x)   ((x) < 0 ? -(x) : (x))
 
#define S_UNIT_X   1.0
 
#define S_UNIT_Y   0.0
 

Functions

static int LongAxis (GLdouble v[3])
 
static void ComputeNormal (GLUtesselator *tess, GLdouble norm[3])
 
static void CheckOrientation (GLUtesselator *tess)
 
void __gl_projectPolygon (GLUtesselator *tess)
 

Macro Definition Documentation

◆ ABS

#define ABS (   x)    ((x) < 0 ? -(x) : (x))

Definition at line 65 of file normal.c.

◆ Dot

#define Dot (   u,
  v 
)    (u[0]*v[0] + u[1]*v[1] + u[2]*v[2])

Definition at line 49 of file normal.c.

◆ FALSE

#define FALSE   0

Definition at line 46 of file normal.c.

◆ S_UNIT_X

#define S_UNIT_X   1.0

Definition at line 190 of file normal.c.

◆ S_UNIT_Y

#define S_UNIT_Y   0.0

Definition at line 191 of file normal.c.

◆ TRUE

#define TRUE   1

Definition at line 43 of file normal.c.

Function Documentation

◆ __gl_projectPolygon()

void __gl_projectPolygon ( GLUtesselator tess)

Definition at line 198 of file normal.c.

199 {
200  GLUvertex *v, *vHead = &tess->mesh->vHead;
201  GLdouble norm[3];
202  GLdouble *sUnit, *tUnit;
203  int i, computedNormal = FALSE;
204 
205  norm[0] = tess->normal[0];
206  norm[1] = tess->normal[1];
207  norm[2] = tess->normal[2];
208  if( norm[0] == 0 && norm[1] == 0 && norm[2] == 0 ) {
209  ComputeNormal( tess, norm );
210  computedNormal = TRUE;
211  }
212  sUnit = tess->sUnit;
213  tUnit = tess->tUnit;
214  i = LongAxis( norm );
215 
216 #if defined(FOR_TRITE_TEST_PROGRAM) || defined(TRUE_PROJECT)
217  /* Choose the initial sUnit vector to be approximately perpendicular
218  * to the normal.
219  */
220  Normalize( norm );
221 
222  sUnit[i] = 0;
223  sUnit[(i+1)%3] = S_UNIT_X;
224  sUnit[(i+2)%3] = S_UNIT_Y;
225 
226  /* Now make it exactly perpendicular */
227  w = Dot( sUnit, norm );
228  sUnit[0] -= w * norm[0];
229  sUnit[1] -= w * norm[1];
230  sUnit[2] -= w * norm[2];
231  Normalize( sUnit );
232 
233  /* Choose tUnit so that (sUnit,tUnit,norm) form a right-handed frame */
234  tUnit[0] = norm[1]*sUnit[2] - norm[2]*sUnit[1];
235  tUnit[1] = norm[2]*sUnit[0] - norm[0]*sUnit[2];
236  tUnit[2] = norm[0]*sUnit[1] - norm[1]*sUnit[0];
237  Normalize( tUnit );
238 #else
239  /* Project perpendicular to a coordinate axis -- better numerically */
240  sUnit[i] = 0;
241  sUnit[(i+1)%3] = S_UNIT_X;
242  sUnit[(i+2)%3] = S_UNIT_Y;
243 
244  tUnit[i] = 0;
245  tUnit[(i+1)%3] = (norm[i] > 0) ? -S_UNIT_Y : S_UNIT_Y;
246  tUnit[(i+2)%3] = (norm[i] > 0) ? S_UNIT_X : -S_UNIT_X;
247 #endif
248 
249  /* Project the vertices onto the sweep plane */
250  for( v = vHead->next; v != vHead; v = v->next ) {
251  v->s = Dot( v->coords, sUnit );
252  v->t = Dot( v->coords, tUnit );
253  }
254  if( computedNormal ) {
255  CheckOrientation( tess );
256  }
257 }
double GLdouble
Definition: gl.h:163
GLubyte GLubyte GLubyte GLubyte w
Definition: glext.h:6102
#define S_UNIT_Y
Definition: normal.c:191
_Tp _STLP_CALL norm(const complex< _Tp > &__z)
Definition: _complex.h:741
static void CheckOrientation(GLUtesselator *tess)
Definition: normal.c:141
GLdouble tUnit[3]
Definition: tess.h:75
static int LongAxis(GLdouble v[3])
Definition: normal.c:67
GLUvertex vHead
Definition: mesh.h:164
GLdouble normal[3]
Definition: tess.h:73
#define Dot(u, v)
Definition: normal.c:49
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
GLdouble sUnit[3]
Definition: tess.h:74
#define TRUE
Definition: normal.c:43
GLUmesh * mesh
Definition: tess.h:66
#define FALSE
Definition: normal.c:46
#define S_UNIT_X
Definition: normal.c:190
const GLdouble * v
Definition: gl.h:2040
GLUvertex * next
Definition: mesh.h:115
static void ComputeNormal(GLUtesselator *tess, GLdouble norm[3])
Definition: normal.c:76

Referenced by gluTessEndPolygon().

◆ CheckOrientation()

static void CheckOrientation ( GLUtesselator tess)
static

Definition at line 141 of file normal.c.

142 {
143  GLdouble area;
144  GLUface *f, *fHead = &tess->mesh->fHead;
145  GLUvertex *v, *vHead = &tess->mesh->vHead;
146  GLUhalfEdge *e;
147 
148  /* When we compute the normal automatically, we choose the orientation
149  * so that the sum of the signed areas of all contours is non-negative.
150  */
151  area = 0;
152  for( f = fHead->next; f != fHead; f = f->next ) {
153  e = f->anEdge;
154  if( e->winding <= 0 ) continue;
155  do {
156  area += (e->Org->s - e->Dst->s) * (e->Org->t + e->Dst->t);
157  e = e->Lnext;
158  } while( e != f->anEdge );
159  }
160  if( area < 0 ) {
161  /* Reverse the orientation by flipping all the t-coordinates */
162  for( v = vHead->next; v != vHead; v = v->next ) {
163  v->t = - v->t;
164  }
165  tess->tUnit[0] = - tess->tUnit[0];
166  tess->tUnit[1] = - tess->tUnit[1];
167  tess->tUnit[2] = - tess->tUnit[2];
168  }
169 }
double GLdouble
Definition: gl.h:163
GLdouble tUnit[3]
Definition: tess.h:75
GLUface * next
Definition: mesh.h:127
GLUvertex vHead
Definition: mesh.h:164
Definition: mesh.h:126
#define e
Definition: ke_i.h:82
GLUface fHead
Definition: mesh.h:165
GLfloat f
Definition: glext.h:7540
GLUmesh * mesh
Definition: tess.h:66
const GLdouble * v
Definition: gl.h:2040
GLUvertex * next
Definition: mesh.h:115
#define f
Definition: ke_i.h:83
static Real area(Real A[2], Real B[2], Real C[2])
Definition: polyDBG.cc:50

Referenced by __gl_projectPolygon().

◆ ComputeNormal()

static void ComputeNormal ( GLUtesselator tess,
GLdouble  norm[3] 
)
static

Definition at line 76 of file normal.c.

77 {
78  GLUvertex *v, *v1, *v2;
79  GLdouble c, tLen2, maxLen2;
80  GLdouble maxVal[3], minVal[3], d1[3], d2[3], tNorm[3];
81  GLUvertex *maxVert[3], *minVert[3];
82  GLUvertex *vHead = &tess->mesh->vHead;
83  int i;
84 
85  maxVal[0] = maxVal[1] = maxVal[2] = -2 * GLU_TESS_MAX_COORD;
86  minVal[0] = minVal[1] = minVal[2] = 2 * GLU_TESS_MAX_COORD;
87 
88  for( v = vHead->next; v != vHead; v = v->next ) {
89  for( i = 0; i < 3; ++i ) {
90  c = v->coords[i];
91  if( c < minVal[i] ) { minVal[i] = c; minVert[i] = v; }
92  if( c > maxVal[i] ) { maxVal[i] = c; maxVert[i] = v; }
93  }
94  }
95 
96  /* Find two vertices separated by at least 1/sqrt(3) of the maximum
97  * distance between any two vertices
98  */
99  i = 0;
100  if( maxVal[1] - minVal[1] > maxVal[0] - minVal[0] ) { i = 1; }
101  if( maxVal[2] - minVal[2] > maxVal[i] - minVal[i] ) { i = 2; }
102  if( minVal[i] >= maxVal[i] ) {
103  /* All vertices are the same -- normal doesn't matter */
104  norm[0] = 0; norm[1] = 0; norm[2] = 1;
105  return;
106  }
107 
108  /* Look for a third vertex which forms the triangle with maximum area
109  * (Length of normal == twice the triangle area)
110  */
111  maxLen2 = 0;
112  v1 = minVert[i];
113  v2 = maxVert[i];
114  d1[0] = v1->coords[0] - v2->coords[0];
115  d1[1] = v1->coords[1] - v2->coords[1];
116  d1[2] = v1->coords[2] - v2->coords[2];
117  for( v = vHead->next; v != vHead; v = v->next ) {
118  d2[0] = v->coords[0] - v2->coords[0];
119  d2[1] = v->coords[1] - v2->coords[1];
120  d2[2] = v->coords[2] - v2->coords[2];
121  tNorm[0] = d1[1]*d2[2] - d1[2]*d2[1];
122  tNorm[1] = d1[2]*d2[0] - d1[0]*d2[2];
123  tNorm[2] = d1[0]*d2[1] - d1[1]*d2[0];
124  tLen2 = tNorm[0]*tNorm[0] + tNorm[1]*tNorm[1] + tNorm[2]*tNorm[2];
125  if( tLen2 > maxLen2 ) {
126  maxLen2 = tLen2;
127  norm[0] = tNorm[0];
128  norm[1] = tNorm[1];
129  norm[2] = tNorm[2];
130  }
131  }
132 
133  if( maxLen2 <= 0 ) {
134  /* All points lie on a single line -- any decent normal will do */
135  norm[0] = norm[1] = norm[2] = 0;
136  norm[LongAxis(d1)] = 1;
137  }
138 }
double GLdouble
Definition: gl.h:163
_Tp _STLP_CALL norm(const complex< _Tp > &__z)
Definition: _complex.h:741
static int LongAxis(GLdouble v[3])
Definition: normal.c:67
GLUvertex vHead
Definition: mesh.h:164
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
GLdouble coords[3]
Definition: mesh.h:121
const GLubyte * c
Definition: glext.h:8905
GLUmesh * mesh
Definition: tess.h:66
GLfloat GLfloat GLfloat v2
Definition: glext.h:6063
const GLdouble * v
Definition: gl.h:2040
GLUvertex * next
Definition: mesh.h:115
#define c
Definition: ke_i.h:80
#define GLU_TESS_MAX_COORD
Definition: glu.h:284
GLfloat GLfloat v1
Definition: glext.h:6062

Referenced by __gl_projectPolygon().

◆ LongAxis()

static int LongAxis ( GLdouble  v[3])
static

Definition at line 67 of file normal.c.

68 {
69  int i = 0;
70 
71  if( ABS(v[1]) > ABS(v[0]) ) { i = 1; }
72  if( ABS(v[2]) > ABS(v[i]) ) { i = 2; }
73  return i;
74 }
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 ABS(x)
Definition: normal.c:65
const GLdouble * v
Definition: gl.h:2040

Referenced by __gl_projectPolygon(), and ComputeNormal().