1/* 2 * Copyright (c) 1993-1997, Silicon Graphics, Inc. 3 * ALL RIGHTS RESERVED 4 * Permission to use, copy, modify, and distribute this software for 5 * any purpose and without fee is hereby granted, provided that the above 6 * copyright notice appear in all copies and that both the copyright notice 7 * and this permission notice appear in supporting documentation, and that 8 * the name of Silicon Graphics, Inc. not be used in advertising 9 * or publicity pertaining to distribution of the software without specific, 10 * written prior permission. 11 * 12 * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU "AS-IS" 13 * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE, 14 * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR 15 * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON 16 * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT, 17 * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY 18 * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION, 19 * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF 20 * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN 21 * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON 22 * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE 23 * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE. 24 * 25 * US Government Users Restricted Rights 26 * Use, duplication, or disclosure by the Government is subject to 27 * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph 28 * (c)(1)(ii) of the Rights in Technical Data and Computer Software 29 * clause at DFARS 252.227-7013 and/or in similar or successor 30 * clauses in the FAR or the DOD or NASA FAR Supplement. 31 * Unpublished-- rights reserved under the copyright laws of the 32 * United States. Contractor/manufacturer is Silicon Graphics, 33 * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311. 34 * 35 * OpenGL(R) is a registered trademark of Silicon Graphics, Inc. 36 */ 37 38/* accpersp.c 39 * Use the accumulation buffer to do full-scene antialiasing 40 * on a scene with perspective projection, using the special 41 * routines accFrustum() and accPerspective(). 42 */ 43#include <stdlib.h> 44#include <math.h> 45#include "glut_wrap.h" 46#include "jitter.h" 47 48#define PI_ 3.14159265358979323846 49 50/* accFrustum() 51 * The first 6 arguments are identical to the glFrustum() call. 52 * 53 * pixdx and pixdy are anti-alias jitter in pixels. 54 * Set both equal to 0.0 for no anti-alias jitter. 55 * eyedx and eyedy are depth-of field jitter in pixels. 56 * Set both equal to 0.0 for no depth of field effects. 57 * 58 * focus is distance from eye to plane in focus. 59 * focus must be greater than, but not equal to 0.0. 60 * 61 * Note that accFrustum() calls glTranslatef(). You will 62 * probably want to insure that your ModelView matrix has been 63 * initialized to identity before calling accFrustum(). 64 */ 65static void accFrustum(GLdouble left, GLdouble right, GLdouble bottom, 66 GLdouble top, GLdouble nnear, GLdouble ffar, GLdouble pixdx, 67 GLdouble pixdy, GLdouble eyedx, GLdouble eyedy, GLdouble focus) 68{ 69 GLdouble xwsize, ywsize; 70 GLdouble dx, dy; 71 GLint viewport[4]; 72 73 glGetIntegerv (GL_VIEWPORT, viewport); 74 75 xwsize = right - left; 76 ywsize = top - bottom; 77 78 dx = -(pixdx*xwsize/(GLdouble) viewport[2] + eyedx*nnear/focus); 79 dy = -(pixdy*ywsize/(GLdouble) viewport[3] + eyedy*nnear/focus); 80 81 glMatrixMode(GL_PROJECTION); 82 glLoadIdentity(); 83 glFrustum (left + dx, right + dx, bottom + dy, top + dy, nnear, ffar); 84 glMatrixMode(GL_MODELVIEW); 85 glLoadIdentity(); 86 glTranslatef (-eyedx, -eyedy, 0.0); 87} 88 89/* accPerspective() 90 * 91 * The first 4 arguments are identical to the gluPerspective() call. 92 * pixdx and pixdy are anti-alias jitter in pixels. 93 * Set both equal to 0.0 for no anti-alias jitter. 94 * eyedx and eyedy are depth-of field jitter in pixels. 95 * Set both equal to 0.0 for no depth of field effects. 96 * 97 * focus is distance from eye to plane in focus. 98 * focus must be greater than, but not equal to 0.0. 99 * 100 * Note that accPerspective() calls accFrustum(). 101 */ 102static void accPerspective(GLdouble fovy, GLdouble aspect, 103 GLdouble nnear, GLdouble ffar, GLdouble pixdx, GLdouble pixdy, 104 GLdouble eyedx, GLdouble eyedy, GLdouble focus) 105{ 106 GLdouble fov2,left,right,bottom,top; 107 108 fov2 = ((fovy*PI_) / 180.0) / 2.0; 109 110 top = nnear / (cos(fov2) / sin(fov2)); 111 bottom = -top; 112 113 right = top * aspect; 114 left = -right; 115 116 accFrustum (left, right, bottom, top, nnear, ffar, 117 pixdx, pixdy, eyedx, eyedy, focus); 118} 119 120/* Initialize lighting and other values. 121 */ 122static void init(void) 123{ 124 GLfloat mat_ambient[] = { 1.0, 1.0, 1.0, 1.0 }; 125 GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 }; 126 GLfloat light_position[] = { 0.0, 0.0, 10.0, 1.0 }; 127 GLfloat lm_ambient[] = { 0.2, 0.2, 0.2, 1.0 }; 128 129 glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient); 130 glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular); 131 glMaterialf(GL_FRONT, GL_SHININESS, 50.0); 132 glLightfv(GL_LIGHT0, GL_POSITION, light_position); 133 glLightModelfv(GL_LIGHT_MODEL_AMBIENT, lm_ambient); 134 135 glEnable(GL_LIGHTING); 136 glEnable(GL_LIGHT0); 137 glEnable(GL_DEPTH_TEST); 138 glShadeModel (GL_FLAT); 139 140 glClearColor(0.0, 0.0, 0.0, 0.0); 141 glClearAccum(0.0, 0.0, 0.0, 0.0); 142} 143 144static void displayObjects(void) 145{ 146 GLfloat torus_diffuse[] = { 0.7, 0.7, 0.0, 1.0 }; 147 GLfloat cube_diffuse[] = { 0.0, 0.7, 0.7, 1.0 }; 148 GLfloat sphere_diffuse[] = { 0.7, 0.0, 0.7, 1.0 }; 149 GLfloat octa_diffuse[] = { 0.7, 0.4, 0.4, 1.0 }; 150 151 glPushMatrix (); 152 glTranslatef (0.0, 0.0, -5.0); 153 glRotatef (30.0, 1.0, 0.0, 0.0); 154 155 glPushMatrix (); 156 glTranslatef (-0.80, 0.35, 0.0); 157 glRotatef (100.0, 1.0, 0.0, 0.0); 158 glMaterialfv(GL_FRONT, GL_DIFFUSE, torus_diffuse); 159 glutSolidTorus (0.275, 0.85, 16, 16); 160 glPopMatrix (); 161 162 glPushMatrix (); 163 glTranslatef (-0.75, -0.50, 0.0); 164 glRotatef (45.0, 0.0, 0.0, 1.0); 165 glRotatef (45.0, 1.0, 0.0, 0.0); 166 glMaterialfv(GL_FRONT, GL_DIFFUSE, cube_diffuse); 167 glutSolidCube (1.5); 168 glPopMatrix (); 169 170 glPushMatrix (); 171 glTranslatef (0.75, 0.60, 0.0); 172 glRotatef (30.0, 1.0, 0.0, 0.0); 173 glMaterialfv(GL_FRONT, GL_DIFFUSE, sphere_diffuse); 174 glutSolidSphere (1.0, 16, 16); 175 glPopMatrix (); 176 177 glPushMatrix (); 178 glTranslatef (0.70, -0.90, 0.25); 179 glMaterialfv(GL_FRONT, GL_DIFFUSE, octa_diffuse); 180 glutSolidOctahedron (); 181 glPopMatrix (); 182 183 glPopMatrix (); 184} 185 186#define ACSIZE 8 187 188static void display(void) 189{ 190 GLint viewport[4]; 191 int jitter; 192 193 glGetIntegerv (GL_VIEWPORT, viewport); 194 195 glClear(GL_ACCUM_BUFFER_BIT); 196 for (jitter = 0; jitter < ACSIZE; jitter++) { 197 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); 198 accPerspective (50.0, 199 (GLdouble) viewport[2]/(GLdouble) viewport[3], 200 1.0, 15.0, j8[jitter].x, j8[jitter].y, 0.0, 0.0, 1.0); 201 displayObjects (); 202 glAccum(GL_ACCUM, 1.0/ACSIZE); 203 } 204 glAccum (GL_RETURN, 1.0); 205 glFlush(); 206} 207 208static void reshape(int w, int h) 209{ 210 glViewport(0, 0, (GLsizei) w, (GLsizei) h); 211} 212 213/* ARGSUSED1 */ 214static void keyboard(unsigned char key, int x, int y) 215{ 216 switch (key) { 217 case 27: 218 exit(0); 219 break; 220 } 221} 222 223/* Main Loop 224 * Be certain you request an accumulation buffer. 225 */ 226int main(int argc, char** argv) 227{ 228 glutInit(&argc, argv); 229 glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB 230 | GLUT_ACCUM | GLUT_DEPTH); 231 glutInitWindowSize (250, 250); 232 glutInitWindowPosition (100, 100); 233 glutCreateWindow (argv[0]); 234 init(); 235 glutReshapeFunc(reshape); 236 glutDisplayFunc(display); 237 glutKeyboardFunc(keyboard); 238 glutMainLoop(); 239 return 0; 240} 241