reactos/lib/glu32/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 ** $Date$ $Revision: 1.1 $
  35 ** $Header: /cygdrive/c/RCVS/CVS/ReactOS/reactos/lib/glu32/libutil/project.c,v 1.1 2004/02/02 16:39:16 navaraf Exp $
  36 */
  37
  38 #include "gluos.h"
  39 #include <math.h>
  40 #include <GL/gl.h>
  41 #include <GL/glu.h>
  42 #include "gluint.h"
  43
  44 /*
  45 ** Make m an identity matrix
  46 */
  47 static void __gluMakeIdentityd(GLdouble m[16])
  48 {
  49     m[0+4*0] = 1; m[0+4*1] = 0; m[0+4*2] = 0; m[0+4*3] = 0;
  50     m[1+4*0] = 0; m[1+4*1] = 1; m[1+4*2] = 0; m[1+4*3] = 0;
  51     m[2+4*0] = 0; m[2+4*1] = 0; m[2+4*2] = 1; m[2+4*3] = 0;
  52     m[3+4*0] = 0; m[3+4*1] = 0; m[3+4*2] = 0; m[3+4*3] = 1;
  53 }
  54
  55 static void __gluMakeIdentityf(GLfloat m[16])
  56 {
  57     m[0+4*0] = 1; m[0+4*1] = 0; m[0+4*2] = 0; m[0+4*3] = 0;
  58     m[1+4*0] = 0; m[1+4*1] = 1; m[1+4*2] = 0; m[1+4*3] = 0;
  59     m[2+4*0] = 0; m[2+4*1] = 0; m[2+4*2] = 1; m[2+4*3] = 0;
  60     m[3+4*0] = 0; m[3+4*1] = 0; m[3+4*2] = 0; m[3+4*3] = 1;
  61 }
  62
  63 void GLAPIENTRY
  64 gluOrtho2D(GLdouble left, GLdouble right, GLdouble bottom, GLdouble top)
  65 {
  66     glOrtho(left, right, bottom, top, -1, 1);
  67 }
  68
  69 #define __glPi 3.14159265358979323846
  70
  71 void GLAPIENTRY
  72 gluPerspective(GLdouble fovy, GLdouble aspect, GLdouble zNear, GLdouble zFar)
  73 {
  74     GLdouble m[4][4];
  75     double sine, cotangent, deltaZ;
  76     double radians = fovy / 2 * __glPi / 180;
  77
  78     deltaZ = zFar - zNear;
  79     sine = sin(radians);
  80     if ((deltaZ == 0) || (sine == 0) || (aspect == 0)) {
  81         return;
  82     }
  83     cotangent = COS(radians) / sine;
  84
  85     __gluMakeIdentityd(&m[0][0]);
  86     m[0][0] = cotangent / aspect;
  87     m[1][1] = cotangent;
  88     m[2][2] = -(zFar + zNear) / deltaZ;
  89     m[2][3] = -1;
  90     m[3][2] = -2 * zNear * zFar / deltaZ;
  91     m[3][3] = 0;
  92     glMultMatrixd(&m[0][0]);
  93 }
  94
  95 static void normalize(float v[3])
  96 {
  97     float r;
  98
  99     r = sqrt( v[0]*v[0] + v[1]*v[1] + v[2]*v[2] );
 100     if (r == 0.0) return;
 101
 102     v[0] /= r;
 103     v[1] /= r;
 104     v[2] /= r;
 105 }
 106
 107 static void cross(float v1[3], float v2[3], float result[3])
 108 {
 109     result[0] = v1[1]*v2[2] - v1[2]*v2[1];
 110     result[1] = v1[2]*v2[0] - v1[0]*v2[2];
 111     result[2] = v1[0]*v2[1] - v1[1]*v2[0];
 112 }
 113
 114 void GLAPIENTRY
 115 gluLookAt(GLdouble eyex, GLdouble eyey, GLdouble eyez, GLdouble centerx,
 116           GLdouble centery, GLdouble centerz, GLdouble upx, GLdouble upy,
 117           GLdouble upz)
 118 {
 119     float forward[3], side[3], up[3];
 120     GLfloat m[4][4];
 121
 122     forward[0] = centerx - eyex;
 123     forward[1] = centery - eyey;
 124     forward[2] = centerz - eyez;
 125
 126     up[0] = upx;
 127     up[1] = upy;
 128     up[2] = upz;
 129
 130     normalize(forward);
 131
 132     /* Side = forward x up */
 133     cross(forward, up, side);
 134     normalize(side);
 135
 136     /* Recompute up as: up = side x forward */
 137     cross(side, forward, up);
 138
 139     __gluMakeIdentityf(&m[0][0]);
 140     m[0][0] = side[0];
 141     m[1][0] = side[1];
 142     m[2][0] = side[2];
 143
 144     m[0][1] = up[0];
 145     m[1][1] = up[1];
 146     m[2][1] = up[2];
 147
 148     m[0][2] = -forward[0];
 149     m[1][2] = -forward[1];
 150     m[2][2] = -forward[2];
 151
 152     glMultMatrixf(&m[0][0]);
 153     glTranslated(-eyex, -eyey, -eyez);
 154 }
 155
 156 static void __gluMultMatrixVecd(const GLdouble matrix[16], const GLdouble in[4],
 157                       GLdouble out[4])
 158 {
 159     int i;
 160
 161     for (i=0; i<4; i++) {
 162         out[i] =
 163             in[0] * matrix[0*4+i] +
 164             in[1] * matrix[1*4+i] +
 165             in[2] * matrix[2*4+i] +
 166             in[3] * matrix[3*4+i];
 167     }
 168 }
 169
 170 /*
 171 ** inverse = invert(src)
 172 */
 173 static int __gluInvertMatrixd(const GLdouble src[16], GLdouble inverse[16])
 174 {
 175     int i, j, k, swap;
 176     double t;
 177     GLdouble temp[4][4];
 178
 179     for (i=0; i<4; i++) {
 180         for (j=0; j<4; j++) {
 181             temp[i][j] = src[i*4+j];
 182         }
 183     }
 184     __gluMakeIdentityd(inverse);
 185
 186     for (i = 0; i < 4; i++) {
 187         /*
 188         ** Look for largest element in column
 189         */
 190         swap = i;
 191         for (j = i + 1; j < 4; j++) {
 192             if (fabs(temp[j][i]) > fabs(temp[i][i])) {
 193                 swap = j;
 194             }
 195         }
 196
 197         if (swap != i) {
 198             /*
 199             ** Swap rows.
 200             */
 201             for (k = 0; k < 4; k++) {
 202                 t = temp[i][k];
 203                 temp[i][k] = temp[swap][k];
 204                 temp[swap][k] = t;
 205
 206                 t = inverse[i*4+k];
 207                 inverse[i*4+k] = inverse[swap*4+k];
 208                 inverse[swap*4+k] = t;
 209             }
 210         }
 211
 212         if (temp[i][i] == 0) {
 213             /*
 214             ** No non-zero pivot.  The matrix is singular, which shouldn't
 215             ** happen.  This means the user gave us a bad matrix.
 216             */
 217             return GL_FALSE;
 218         }
 219
 220         t = temp[i][i];
 221         for (k = 0; k < 4; k++) {
 222             temp[i][k] /= t;
 223             inverse[i*4+k] /= t;
 224         }
 225         for (j = 0; j < 4; j++) {
 226             if (j != i) {
 227                 t = temp[j][i];
 228                 for (k = 0; k < 4; k++) {
 229                     temp[j][k] -= temp[i][k]*t;
 230                     inverse[j*4+k] -= inverse[i*4+k]*t;
 231                 }
 232             }
 233         }
 234     }
 235     return GL_TRUE;
 236 }
 237
 238 static void __gluMultMatricesd(const GLdouble a[16], const GLdouble b[16],
 239                                 GLdouble r[16])
 240 {
 241     int i, j;
 242
 243     for (i = 0; i < 4; i++) {
 244         for (j = 0; j < 4; j++) {
 245             r[i*4+j] =
 246                 a[i*4+0]*b[0*4+j] +
 247                 a[i*4+1]*b[1*4+j] +
 248                 a[i*4+2]*b[2*4+j] +
 249                 a[i*4+3]*b[3*4+j];
 250         }
 251     }
 252 }
 253
 254 GLint GLAPIENTRY
 255 gluProject(GLdouble objx, GLdouble objy, GLdouble objz,
 256               const GLdouble modelMatrix[16],
 257               const GLdouble projMatrix[16],
 258               const GLint viewport[4],
 259               GLdouble *winx, GLdouble *winy, GLdouble *winz)
 260 {
 261     double in[4];
 262     double out[4];
 263
 264     in[0]=objx;
 265     in[1]=objy;
 266     in[2]=objz;
 267     in[3]=1.0;
 268     __gluMultMatrixVecd(modelMatrix, in, out);
 269     __gluMultMatrixVecd(projMatrix, out, in);
 270     if (in[3] == 0.0) return(GL_FALSE);
 271     in[0] /= in[3];
 272     in[1] /= in[3];
 273     in[2] /= in[3];
 274     /* Map x, y and z to range 0-1 */
 275     in[0] = in[0] * 0.5 + 0.5;
 276     in[1] = in[1] * 0.5 + 0.5;
 277     in[2] = in[2] * 0.5 + 0.5;
 278
 279     /* Map x,y to viewport */
 280     in[0] = in[0] * viewport[2] + viewport[0];
 281     in[1] = in[1] * viewport[3] + viewport[1];
 282
 283     *winx=in[0];
 284     *winy=in[1];
 285     *winz=in[2];
 286     return(GL_TRUE);
 287 }
 288
 289 GLint GLAPIENTRY
 290 gluUnProject(GLdouble winx, GLdouble winy, GLdouble winz,
 291                 const GLdouble modelMatrix[16],
 292                 const GLdouble projMatrix[16],
 293                 const GLint viewport[4],
 294                 GLdouble *objx, GLdouble *objy, GLdouble *objz)
 295 {
 296     double finalMatrix[16];
 297     double in[4];
 298     double out[4];
 299
 300     __gluMultMatricesd(modelMatrix, projMatrix, finalMatrix);
 301     if (!__gluInvertMatrixd(finalMatrix, finalMatrix)) return(GL_FALSE);
 302
 303     in[0]=winx;
 304     in[1]=winy;
 305     in[2]=winz;
 306     in[3]=1.0;
 307
 308     /* Map x and y from window coordinates */
 309     in[0] = (in[0] - viewport[0]) / viewport[2];
 310     in[1] = (in[1] - viewport[1]) / viewport[3];
 311
 312     /* Map to range -1 to 1 */
 313     in[0] = in[0] * 2 - 1;
 314     in[1] = in[1] * 2 - 1;
 315     in[2] = in[2] * 2 - 1;
 316
 317     __gluMultMatrixVecd(finalMatrix, in, out);
 318     if (out[3] == 0.0) return(GL_FALSE);
 319     out[0] /= out[3];
 320     out[1] /= out[3];
 321     out[2] /= out[3];
 322     *objx = out[0];
 323     *objy = out[1];
 324     *objz = out[2];
 325     return(GL_TRUE);
 326 }
 327
 328 GLint GLAPIENTRY
 329 gluUnProject4(GLdouble winx, GLdouble winy, GLdouble winz, GLdouble clipw,
 330               const GLdouble modelMatrix[16],
 331               const GLdouble projMatrix[16],
 332               const GLint viewport[4],
 333               GLclampd nearVal, GLclampd farVal,
 334               GLdouble *objx, GLdouble *objy, GLdouble *objz,
 335               GLdouble *objw)
 336 {
 337     double finalMatrix[16];
 338     double in[4];
 339     double out[4];
 340
 341     __gluMultMatricesd(modelMatrix, projMatrix, finalMatrix);
 342     if (!__gluInvertMatrixd(finalMatrix, finalMatrix)) return(GL_FALSE);
 343
 344     in[0]=winx;
 345     in[1]=winy;
 346     in[2]=winz;
 347     in[3]=clipw;
 348
 349     /* Map x and y from window coordinates */
 350     in[0] = (in[0] - viewport[0]) / viewport[2];
 351     in[1] = (in[1] - viewport[1]) / viewport[3];
 352     in[2] = (in[2] - nearVal) / (farVal - nearVal);
 353
 354     /* Map to range -1 to 1 */
 355     in[0] = in[0] * 2 - 1;
 356     in[1] = in[1] * 2 - 1;
 357     in[2] = in[2] * 2 - 1;
 358
 359     __gluMultMatrixVecd(finalMatrix, in, out);
 360     if (out[3] == 0.0) return(GL_FALSE);
 361     *objx = out[0];
 362     *objy = out[1];
 363     *objz = out[2];
 364     *objw = out[3];
 365     return(GL_TRUE);
 366 }
 367
 368 void GLAPIENTRY
 369 gluPickMatrix(GLdouble x, GLdouble y, GLdouble deltax, GLdouble deltay,
 370                   GLint viewport[4])
 371 {
 372     if (deltax <= 0 || deltay <= 0) {
 373         return;
 374     }
 375
 376     /* Translate and scale the picked region to the entire window */
 377     glTranslatef((viewport[2] - 2 * (x - viewport[0])) / deltax,
 378             (viewport[3] - 2 * (y - viewport[1])) / deltay, 0);
 379     glScalef(viewport[2] / deltax, viewport[3] / deltay, 1.0);
 380 }