src/glu/sgi/libutil/project.c

   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 #include "gluos.h"
  37 #include <math.h>
  38 #include <GL/gl.h>
  39 #include <GL/glu.h>
  40 #include "gluint.h"
  41
  42 /*
  43 ** Make m an identity matrix
  44 */
  45 static void __gluMakeIdentityd(GLdouble m[16])
  46 {
  47     m[0+4*0] = 1; m[0+4*1] = 0; m[0+4*2] = 0; m[0+4*3] = 0;
  48     m[1+4*0] = 0; m[1+4*1] = 1; m[1+4*2] = 0; m[1+4*3] = 0;
  49     m[2+4*0] = 0; m[2+4*1] = 0; m[2+4*2] = 1; m[2+4*3] = 0;
  50     m[3+4*0] = 0; m[3+4*1] = 0; m[3+4*2] = 0; m[3+4*3] = 1;
  51 }
  52
  53 static void __gluMakeIdentityf(GLfloat m[16])
  54 {
  55     m[0+4*0] = 1; m[0+4*1] = 0; m[0+4*2] = 0; m[0+4*3] = 0;
  56     m[1+4*0] = 0; m[1+4*1] = 1; m[1+4*2] = 0; m[1+4*3] = 0;
  57     m[2+4*0] = 0; m[2+4*1] = 0; m[2+4*2] = 1; m[2+4*3] = 0;
  58     m[3+4*0] = 0; m[3+4*1] = 0; m[3+4*2] = 0; m[3+4*3] = 1;
  59 }
  60
  61 void GLAPIENTRY
  62 gluOrtho2D(GLdouble left, GLdouble right, GLdouble bottom, GLdouble top)
  63 {
  64     glOrtho(left, right, bottom, top, -1, 1);
  65 }
  66
  67 #define __glPi 3.14159265358979323846
  68
  69 void GLAPIENTRY
  70 gluPerspective(GLdouble fovy, GLdouble aspect, GLdouble zNear, GLdouble zFar)
  71 {
  72     GLdouble m[4][4];
  73     double sine, cotangent, deltaZ;
  74     double radians = fovy / 2 * __glPi / 180;
  75
  76     deltaZ = zFar - zNear;
  77     sine = sin(radians);
  78     if ((deltaZ == 0) || (sine == 0) || (aspect == 0)) {
  79         return;
  80     }
  81     cotangent = COS(radians) / sine;
  82
  83     __gluMakeIdentityd(&m[0][0]);
  84     m[0][0] = cotangent / aspect;
  85     m[1][1] = cotangent;
  86     m[2][2] = -(zFar + zNear) / deltaZ;
  87     m[2][3] = -1;
  88     m[3][2] = -2 * zNear * zFar / deltaZ;
  89     m[3][3] = 0;
  90     glMultMatrixd(&m[0][0]);
  91 }
  92
  93 static void normalize(float v[3])
  94 {
  95     float r;
  96
  97     r = sqrt( v[0]*v[0] + v[1]*v[1] + v[2]*v[2] );
  98     if (r == 0.0) return;
  99
 100     v[0] /= r;
 101     v[1] /= r;
 102     v[2] /= r;
 103 }
 104
 105 static void cross(float v1[3], float v2[3], float result[3])
 106 {
 107     result[0] = v1[1]*v2[2] - v1[2]*v2[1];
 108     result[1] = v1[2]*v2[0] - v1[0]*v2[2];
 109     result[2] = v1[0]*v2[1] - v1[1]*v2[0];
 110 }
 111
 112 void GLAPIENTRY
 113 gluLookAt(GLdouble eyex, GLdouble eyey, GLdouble eyez, GLdouble centerx,
 114           GLdouble centery, GLdouble centerz, GLdouble upx, GLdouble upy,
 115           GLdouble upz)
 116 {
 117     float forward[3], side[3], up[3];
 118     GLfloat m[4][4];
 119
 120     forward[0] = centerx - eyex;
 121     forward[1] = centery - eyey;
 122     forward[2] = centerz - eyez;
 123
 124     up[0] = upx;
 125     up[1] = upy;
 126     up[2] = upz;
 127
 128     normalize(forward);
 129
 130     /* Side = forward x up */
 131     cross(forward, up, side);
 132     normalize(side);
 133
 134     /* Recompute up as: up = side x forward */
 135     cross(side, forward, up);
 136
 137     __gluMakeIdentityf(&m[0][0]);
 138     m[0][0] = side[0];
 139     m[1][0] = side[1];
 140     m[2][0] = side[2];
 141
 142     m[0][1] = up[0];
 143     m[1][1] = up[1];
 144     m[2][1] = up[2];
 145
 146     m[0][2] = -forward[0];
 147     m[1][2] = -forward[1];
 148     m[2][2] = -forward[2];
 149
 150     glMultMatrixf(&m[0][0]);
 151     glTranslated(-eyex, -eyey, -eyez);
 152 }
 153
 154 static void __gluMultMatrixVecd(const GLdouble matrix[16], const GLdouble in[4],
 155                       GLdouble out[4])
 156 {
 157     int i;
 158
 159     for (i=0; i<4; i++) {
 160         out[i] =
 161             in[0] * matrix[0*4+i] +
 162             in[1] * matrix[1*4+i] +
 163             in[2] * matrix[2*4+i] +
 164             in[3] * matrix[3*4+i];
 165     }
 166 }
 167
 168 /*
 169 ** inverse = invert(src)
 170 ** New, faster implementation by Shan Hao Bo, April 2006.
 171 */
 172 static int __gluInvertMatrixd(const GLdouble src[16], GLdouble inverse[16])
 173 {
 174         int i, j, k;
 175         double t;
 176         GLdouble temp[4][4];
 177
 178         for (i=0; i<4; i++) {
 179                 for (j=0; j<4; j++) {
 180                     temp[i][j] = src[i*4+j];
 181                 }
 182         }
 183         __gluMakeIdentityd(inverse);
 184
 185         for (i = 0; i < 4; i++) {
 186                 if (temp[i][i] == 0.0f) {
 187                     /*
 188                     ** Look for non-zero element in column
 189                     */
 190                     for (j = i + 1; j < 4; j++) {
 191                                 if (temp[j][i] != 0.0f) {
 192                                     break;
 193                                 }
 194                     }
 195
 196                     if (j != 4) {
 197                                 /*
 198                                  ** Swap rows.
 199                                  */
 200                                 for (k = 0; k < 4; k++) {
 201                                     t = temp[i][k];
 202                                     temp[i][k] = temp[j][k];
 203                                     temp[j][k] = t;
 204
 205                                     t = inverse[i*4+k];
 206                                     inverse[i*4+k] = inverse[j*4+k];
 207                                     inverse[j*4+k] = t;
 208                                 }
 209                     }
 210                     else {
 211                                 /*
 212                                 ** No non-zero pivot.  The matrix is singular,
 213 which shouldn't
 214                                 ** happen.  This means the user gave us a bad
 215 matrix.
 216                                 */
 217                                 return GL_FALSE;
 218                     }
 219                 }
 220
 221                 t = 1.0f / temp[i][i];
 222                 for (k = 0; k < 4; k++) {
 223                     temp[i][k] *= t;
 224                     inverse[i*4+k] *= t;
 225                 }
 226                 for (j = 0; j < 4; j++) {
 227                     if (j != i) {
 228                                 t = temp[j][i];
 229                                 for (k = 0; k < 4; k++) {
 230                                             temp[j][k] -= temp[i][k]*t;
 231                                             inverse[j*4+k] -= inverse[i*4+k]*t;
 232                                 }
 233                     }
 234                 }
 235         }
 236         return GL_TRUE;
 237 }
 238
 239 static void __gluMultMatricesd(const GLdouble a[16], const GLdouble b[16],
 240                                 GLdouble r[16])
 241 {
 242     int i, j;
 243
 244     for (i = 0; i < 4; i++) {
 245         for (j = 0; j < 4; j++) {
 246             r[i*4+j] =
 247                 a[i*4+0]*b[0*4+j] +
 248                 a[i*4+1]*b[1*4+j] +
 249                 a[i*4+2]*b[2*4+j] +
 250                 a[i*4+3]*b[3*4+j];
 251         }
 252     }
 253 }
 254
 255 GLint GLAPIENTRY
 256 gluProject(GLdouble objx, GLdouble objy, GLdouble objz,
 257               const GLdouble modelMatrix[16],
 258               const GLdouble projMatrix[16],
 259               const GLint viewport[4],
 260               GLdouble *winx, GLdouble *winy, GLdouble *winz)
 261 {
 262     double in[4];
 263     double out[4];
 264
 265     in[0]=objx;
 266     in[1]=objy;
 267     in[2]=objz;
 268     in[3]=1.0;
 269     __gluMultMatrixVecd(modelMatrix, in, out);
 270     __gluMultMatrixVecd(projMatrix, out, in);
 271     if (in[3] == 0.0) return(GL_FALSE);
 272     in[0] /= in[3];
 273     in[1] /= in[3];
 274     in[2] /= in[3];
 275     /* Map x, y and z to range 0-1 */
 276     in[0] = in[0] * 0.5 + 0.5;
 277     in[1] = in[1] * 0.5 + 0.5;
 278     in[2] = in[2] * 0.5 + 0.5;
 279
 280     /* Map x,y to viewport */
 281     in[0] = in[0] * viewport[2] + viewport[0];
 282     in[1] = in[1] * viewport[3] + viewport[1];
 283
 284     *winx=in[0];
 285     *winy=in[1];
 286     *winz=in[2];
 287     return(GL_TRUE);
 288 }
 289
 290 GLint GLAPIENTRY
 291 gluUnProject(GLdouble winx, GLdouble winy, GLdouble winz,
 292                 const GLdouble modelMatrix[16],
 293                 const GLdouble projMatrix[16],
 294                 const GLint viewport[4],
 295                 GLdouble *objx, GLdouble *objy, GLdouble *objz)
 296 {
 297     double finalMatrix[16];
 298     double in[4];
 299     double out[4];
 300
 301     __gluMultMatricesd(modelMatrix, projMatrix, finalMatrix);
 302     if (!__gluInvertMatrixd(finalMatrix, finalMatrix)) return(GL_FALSE);
 303
 304     in[0]=winx;
 305     in[1]=winy;
 306     in[2]=winz;
 307     in[3]=1.0;
 308
 309     /* Map x and y from window coordinates */
 310     in[0] = (in[0] - viewport[0]) / viewport[2];
 311     in[1] = (in[1] - viewport[1]) / viewport[3];
 312
 313     /* Map to range -1 to 1 */
 314     in[0] = in[0] * 2 - 1;
 315     in[1] = in[1] * 2 - 1;
 316     in[2] = in[2] * 2 - 1;
 317
 318     __gluMultMatrixVecd(finalMatrix, in, out);
 319     if (out[3] == 0.0) return(GL_FALSE);
 320     out[0] /= out[3];
 321     out[1] /= out[3];
 322     out[2] /= out[3];
 323     *objx = out[0];
 324     *objy = out[1];
 325     *objz = out[2];
 326     return(GL_TRUE);
 327 }
 328
 329 GLint GLAPIENTRY
 330 gluUnProject4(GLdouble winx, GLdouble winy, GLdouble winz, GLdouble clipw,
 331               const GLdouble modelMatrix[16],
 332               const GLdouble projMatrix[16],
 333               const GLint viewport[4],
 334               GLclampd nearVal, GLclampd farVal,
 335               GLdouble *objx, GLdouble *objy, GLdouble *objz,
 336               GLdouble *objw)
 337 {
 338     double finalMatrix[16];
 339     double in[4];
 340     double out[4];
 341
 342     __gluMultMatricesd(modelMatrix, projMatrix, finalMatrix);
 343     if (!__gluInvertMatrixd(finalMatrix, finalMatrix)) return(GL_FALSE);
 344
 345     in[0]=winx;
 346     in[1]=winy;
 347     in[2]=winz;
 348     in[3]=clipw;
 349
 350     /* Map x and y from window coordinates */
 351     in[0] = (in[0] - viewport[0]) / viewport[2];
 352     in[1] = (in[1] - viewport[1]) / viewport[3];
 353     in[2] = (in[2] - nearVal) / (farVal - nearVal);
 354
 355     /* Map to range -1 to 1 */
 356     in[0] = in[0] * 2 - 1;
 357     in[1] = in[1] * 2 - 1;
 358     in[2] = in[2] * 2 - 1;
 359
 360     __gluMultMatrixVecd(finalMatrix, in, out);
 361     if (out[3] == 0.0) return(GL_FALSE);
 362     *objx = out[0];
 363     *objy = out[1];
 364     *objz = out[2];
 365     *objw = out[3];
 366     return(GL_TRUE);
 367 }
 368
 369 void GLAPIENTRY
 370 gluPickMatrix(GLdouble x, GLdouble y, GLdouble deltax, GLdouble deltay,
 371                   GLint viewport[4])
 372 {
 373     if (deltax <= 0 || deltay <= 0) {
 374         return;
 375     }
 376
 377     /* Translate and scale the picked region to the entire window */
 378     glTranslatef((viewport[2] - 2 * (x - viewport[0])) / deltax,
 379             (viewport[3] - 2 * (y - viewport[1])) / deltay, 0);
 380     glScalef(viewport[2] / deltax, viewport[3] / deltay, 1.0);
 381 }