progs/xdemos/glxgears.c

   1 /*
   2  * Copyright (C) 1999-2001  Brian Paul   All Rights Reserved.
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice shall be included
  12  * in all copies or substantial portions of the Software.
  13  *
  14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  15  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  17  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  18  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  19  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  20  */
  21
  22 /*
  23  * This is a port of the infamous "gears" demo to straight GLX (i.e. no GLUT)
  24  * Port by Brian Paul  23 March 2001
  25  *
  26  * Command line options:
  27  *    -info      print GL implementation information
  28  *
  29  */
  30
  31
  32 #include <math.h>
  33 #include <stdlib.h>
  34 #include <stdio.h>
  35 #include <string.h>
  36 #include <X11/Xlib.h>
  37 #include <X11/keysym.h>
  38 #include <GL/gl.h>
  39 #include <GL/glx.h>
  40
  41
  42 #define BENCHMARK
  43
  44 #ifdef BENCHMARK
  45
  46 /* XXX this probably isn't very portable */
  47
  48 #include <sys/time.h>
  49 #include <unistd.h>
  50
  51 /* return current time (in seconds) */
  52 static int
  53 current_time(void)
  54 {
  55    struct timeval tv;
  56    struct timezone tz;
  57    (void) gettimeofday(&tv, &tz);
  58    return (int) tv.tv_sec;
  59 }
  60
  61 #else /*BENCHMARK*/
  62
  63 /* dummy */
  64 static int
  65 current_time(void)
  66 {
  67    return 0;
  68 }
  69
  70 #endif /*BENCHMARK*/
  71
  72
  73
  74 #ifndef M_PI
  75 #define M_PI 3.14159265
  76 #endif
  77
  78
  79 static GLfloat view_rotx = 20.0, view_roty = 30.0, view_rotz = 0.0;
  80 static GLint gear1, gear2, gear3;
  81 static GLfloat angle = 0.0;
  82
  83
  84 /*
  85  *
  86  *  Draw a gear wheel.  You'll probably want to call this function when
  87  *  building a display list since we do a lot of trig here.
  88  *
  89  *  Input:  inner_radius - radius of hole at center
  90  *          outer_radius - radius at center of teeth
  91  *          width - width of gear
  92  *          teeth - number of teeth
  93  *          tooth_depth - depth of tooth
  94  */
  95 static void
  96 gear(GLfloat inner_radius, GLfloat outer_radius, GLfloat width,
  97      GLint teeth, GLfloat tooth_depth)
  98 {
  99    GLint i;
 100    GLfloat r0, r1, r2;
 101    GLfloat angle, da;
 102    GLfloat u, v, len;
 103
 104    r0 = inner_radius;
 105    r1 = outer_radius - tooth_depth / 2.0;
 106    r2 = outer_radius + tooth_depth / 2.0;
 107
 108    da = 2.0 * M_PI / teeth / 4.0;
 109
 110    glShadeModel(GL_FLAT);
 111
 112    glNormal3f(0.0, 0.0, 1.0);
 113
 114    /* draw front face */
 115    glBegin(GL_QUAD_STRIP);
 116    for (i = 0; i <= teeth; i++) {
 117       angle = i * 2.0 * M_PI / teeth;
 118       glVertex3f(r0 * cos(angle), r0 * sin(angle), width * 0.5);
 119       glVertex3f(r1 * cos(angle), r1 * sin(angle), width * 0.5);
 120       if (i < teeth) {
 121          glVertex3f(r0 * cos(angle), r0 * sin(angle), width * 0.5);
 122          glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
 123                     width * 0.5);
 124       }
 125    }
 126    glEnd();
 127
 128    /* draw front sides of teeth */
 129    glBegin(GL_QUADS);
 130    da = 2.0 * M_PI / teeth / 4.0;
 131    for (i = 0; i < teeth; i++) {
 132       angle = i * 2.0 * M_PI / teeth;
 133
 134       glVertex3f(r1 * cos(angle), r1 * sin(angle), width * 0.5);
 135       glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), width * 0.5);
 136       glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da),
 137                  width * 0.5);
 138       glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
 139                  width * 0.5);
 140    }
 141    glEnd();
 142
 143    glNormal3f(0.0, 0.0, -1.0);
 144
 145    /* draw back face */
 146    glBegin(GL_QUAD_STRIP);
 147    for (i = 0; i <= teeth; i++) {
 148       angle = i * 2.0 * M_PI / teeth;
 149       glVertex3f(r1 * cos(angle), r1 * sin(angle), -width * 0.5);
 150       glVertex3f(r0 * cos(angle), r0 * sin(angle), -width * 0.5);
 151       if (i < teeth) {
 152          glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
 153                     -width * 0.5);
 154          glVertex3f(r0 * cos(angle), r0 * sin(angle), -width * 0.5);
 155       }
 156    }
 157    glEnd();
 158
 159    /* draw back sides of teeth */
 160    glBegin(GL_QUADS);
 161    da = 2.0 * M_PI / teeth / 4.0;
 162    for (i = 0; i < teeth; i++) {
 163       angle = i * 2.0 * M_PI / teeth;
 164
 165       glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
 166                  -width * 0.5);
 167       glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da),
 168                  -width * 0.5);
 169       glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), -width * 0.5);
 170       glVertex3f(r1 * cos(angle), r1 * sin(angle), -width * 0.5);
 171    }
 172    glEnd();
 173
 174    /* draw outward faces of teeth */
 175    glBegin(GL_QUAD_STRIP);
 176    for (i = 0; i < teeth; i++) {
 177       angle = i * 2.0 * M_PI / teeth;
 178
 179       glVertex3f(r1 * cos(angle), r1 * sin(angle), width * 0.5);
 180       glVertex3f(r1 * cos(angle), r1 * sin(angle), -width * 0.5);
 181       u = r2 * cos(angle + da) - r1 * cos(angle);
 182       v = r2 * sin(angle + da) - r1 * sin(angle);
 183       len = sqrt(u * u + v * v);
 184       u /= len;
 185       v /= len;
 186       glNormal3f(v, -u, 0.0);
 187       glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), width * 0.5);
 188       glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), -width * 0.5);
 189       glNormal3f(cos(angle), sin(angle), 0.0);
 190       glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da),
 191                  width * 0.5);
 192       glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da),
 193                  -width * 0.5);
 194       u = r1 * cos(angle + 3 * da) - r2 * cos(angle + 2 * da);
 195       v = r1 * sin(angle + 3 * da) - r2 * sin(angle + 2 * da);
 196       glNormal3f(v, -u, 0.0);
 197       glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
 198                  width * 0.5);
 199       glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
 200                  -width * 0.5);
 201       glNormal3f(cos(angle), sin(angle), 0.0);
 202    }
 203
 204    glVertex3f(r1 * cos(0), r1 * sin(0), width * 0.5);
 205    glVertex3f(r1 * cos(0), r1 * sin(0), -width * 0.5);
 206
 207    glEnd();
 208
 209    glShadeModel(GL_SMOOTH);
 210
 211    /* draw inside radius cylinder */
 212    glBegin(GL_QUAD_STRIP);
 213    for (i = 0; i <= teeth; i++) {
 214       angle = i * 2.0 * M_PI / teeth;
 215       glNormal3f(-cos(angle), -sin(angle), 0.0);
 216       glVertex3f(r0 * cos(angle), r0 * sin(angle), -width * 0.5);
 217       glVertex3f(r0 * cos(angle), r0 * sin(angle), width * 0.5);
 218    }
 219    glEnd();
 220 }
 221
 222
 223 static void
 224 draw(void)
 225 {
 226    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 227
 228    glPushMatrix();
 229    glRotatef(view_rotx, 1.0, 0.0, 0.0);
 230    glRotatef(view_roty, 0.0, 1.0, 0.0);
 231    glRotatef(view_rotz, 0.0, 0.0, 1.0);
 232
 233    glPushMatrix();
 234    glTranslatef(-3.0, -2.0, 0.0);
 235    glRotatef(angle, 0.0, 0.0, 1.0);
 236    glCallList(gear1);
 237    glPopMatrix();
 238
 239    glPushMatrix();
 240    glTranslatef(3.1, -2.0, 0.0);
 241    glRotatef(-2.0 * angle - 9.0, 0.0, 0.0, 1.0);
 242    glCallList(gear2);
 243    glPopMatrix();
 244
 245    glPushMatrix();
 246    glTranslatef(-3.1, 4.2, 0.0);
 247    glRotatef(-2.0 * angle - 25.0, 0.0, 0.0, 1.0);
 248    glCallList(gear3);
 249    glPopMatrix();
 250
 251    glPopMatrix();
 252 }
 253
 254
 255 /* new window size or exposure */
 256 static void
 257 reshape(int width, int height)
 258 {
 259    GLfloat h = (GLfloat) height / (GLfloat) width;
 260
 261    glViewport(0, 0, (GLint) width, (GLint) height);
 262    glMatrixMode(GL_PROJECTION);
 263    glLoadIdentity();
 264    glFrustum(-1.0, 1.0, -h, h, 5.0, 60.0);
 265    glMatrixMode(GL_MODELVIEW);
 266    glLoadIdentity();
 267    glTranslatef(0.0, 0.0, -40.0);
 268 }
 269
 270
 271 static void
 272 init(void)
 273 {
 274    static GLfloat pos[4] = { 5.0, 5.0, 10.0, 0.0 };
 275    static GLfloat red[4] = { 0.8, 0.1, 0.0, 1.0 };
 276    static GLfloat green[4] = { 0.0, 0.8, 0.2, 1.0 };
 277    static GLfloat blue[4] = { 0.2, 0.2, 1.0, 1.0 };
 278
 279    glLightfv(GL_LIGHT0, GL_POSITION, pos);
 280    glEnable(GL_CULL_FACE);
 281    glEnable(GL_LIGHTING);
 282    glEnable(GL_LIGHT0);
 283    glEnable(GL_DEPTH_TEST);
 284
 285    /* make the gears */
 286    gear1 = glGenLists(1);
 287    glNewList(gear1, GL_COMPILE);
 288    glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, red);
 289    gear(1.0, 4.0, 1.0, 20, 0.7);
 290    glEndList();
 291
 292    gear2 = glGenLists(1);
 293    glNewList(gear2, GL_COMPILE);
 294    glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, green);
 295    gear(0.5, 2.0, 2.0, 10, 0.7);
 296    glEndList();
 297
 298    gear3 = glGenLists(1);
 299    glNewList(gear3, GL_COMPILE);
 300    glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, blue);
 301    gear(1.3, 2.0, 0.5, 10, 0.7);
 302    glEndList();
 303
 304    glEnable(GL_NORMALIZE);
 305 }
 306
 307
 308 /*
 309  * Create an RGB, double-buffered window.
 310  * Return the window and context handles.
 311  */
 312 static void
 313 make_window( Display *dpy, const char *name,
 314              int x, int y, int width, int height,
 315              Window *winRet, GLXContext *ctxRet)
 316 {
 317    int attrib[] = { GLX_RGBA,
 318                     GLX_RED_SIZE, 1,
 319                     GLX_GREEN_SIZE, 1,
 320                     GLX_BLUE_SIZE, 1,
 321                     GLX_DOUBLEBUFFER,
 322                     GLX_DEPTH_SIZE, 1,
 323                     None };
 324    int scrnum;
 325    XSetWindowAttributes attr;
 326    unsigned long mask;
 327    Window root;
 328    Window win;
 329    GLXContext ctx;
 330    XVisualInfo *visinfo;
 331
 332    scrnum = DefaultScreen( dpy );
 333    root = RootWindow( dpy, scrnum );
 334
 335    visinfo = glXChooseVisual( dpy, scrnum, attrib );
 336    if (!visinfo) {
 337       printf("Error: couldn't get an RGB, Double-buffered visual\n");
 338       exit(1);
 339    }
 340
 341    /* window attributes */
 342    attr.background_pixel = 0;
 343    attr.border_pixel = 0;
 344    attr.colormap = XCreateColormap( dpy, root, visinfo->visual, AllocNone);
 345    attr.event_mask = StructureNotifyMask | ExposureMask | KeyPressMask;
 346    mask = CWBackPixel | CWBorderPixel | CWColormap | CWEventMask;
 347
 348    win = XCreateWindow( dpy, root, 0, 0, width, height,
 349                         0, visinfo->depth, InputOutput,
 350                         visinfo->visual, mask, &attr );
 351
 352    /* set hints and properties */
 353    {
 354       XSizeHints sizehints;
 355       sizehints.x = x;
 356       sizehints.y = y;
 357       sizehints.width  = width;
 358       sizehints.height = height;
 359       sizehints.flags = USSize | USPosition;
 360       XSetNormalHints(dpy, win, &sizehints);
 361       XSetStandardProperties(dpy, win, name, name,
 362                               None, (char **)NULL, 0, &sizehints);
 363    }
 364
 365    ctx = glXCreateContext( dpy, visinfo, NULL, True );
 366    if (!ctx) {
 367       printf("Error: glXCreateContext failed\n");
 368       exit(1);
 369    }
 370
 371    XFree(visinfo);
 372
 373    *winRet = win;
 374    *ctxRet = ctx;
 375 }
 376
 377
 378 static void
 379 event_loop(Display *dpy, Window win)
 380 {
 381    while (1) {
 382       while (XPending(dpy) > 0) {
 383          XEvent event;
 384          XNextEvent(dpy, &event);
 385          switch (event.type) {
 386          case Expose:
 387             /* we'll redraw below */
 388             break;
 389          case ConfigureNotify:
 390             reshape(event.xconfigure.width, event.xconfigure.height);
 391             break;
 392          case KeyPress:
 393             {
 394                char buffer[10];
 395                int r, code;
 396                code = XLookupKeysym(&event.xkey, 0);
 397                if (code == XK_Left) {
 398                   view_roty += 5.0;
 399                }
 400                else if (code == XK_Right) {
 401                   view_roty -= 5.0;
 402                }
 403                else if (code == XK_Up) {
 404                   view_rotx += 5.0;
 405                }
 406                else if (code == XK_Down) {
 407                   view_rotx -= 5.0;
 408                }
 409                else {
 410                   r = XLookupString(&event.xkey, buffer, sizeof(buffer),
 411                                     NULL, NULL);
 412                   if (buffer[0] == 27) {
 413                      /* escape */
 414                      return;
 415                   }
 416                }
 417             }
 418          }
 419       }
 420
 421       /* next frame */
 422       angle += 2.0;
 423
 424       draw();
 425       glXSwapBuffers(dpy, win);
 426
 427       /* calc framerate */
 428       {
 429          static int t0 = -1;
 430          static int frames = 0;
 431          int t = current_time();
 432
 433          if (t0 < 0)
 434             t0 = t;
 435
 436          frames++;
 437
 438          if (t - t0 >= 5.0) {
 439             GLfloat seconds = t - t0;
 440             GLfloat fps = frames / seconds;
 441             printf("%d frames in %3.1f seconds = %6.3f FPS\n", frames, seconds,
 442                    fps);
 443             t0 = t;
 444             frames = 0;
 445          }
 446       }
 447    }
 448 }
 449
 450
 451 int
 452 main(int argc, char *argv[])
 453 {
 454    Display *dpy;
 455    Window win;
 456    GLXContext ctx;
 457    char *dpyName = ":0";
 458    GLboolean printInfo = GL_FALSE;
 459    int i;
 460
 461    for (i = 1; i < argc; i++) {
 462       if (strcmp(argv[i], "-display") == 0) {
 463          dpyName = argv[i+1];
 464          i++;
 465       }
 466       else if (strcmp(argv[i], "-info") == 0) {
 467          printInfo = GL_TRUE;
 468       }
 469    }
 470
 471    dpy = XOpenDisplay(dpyName);
 472    if (!dpy) {
 473       printf("Error: couldn't open display %s\n", dpyName);
 474       return -1;
 475    }
 476
 477    make_window(dpy, "glxgears", 0, 0, 300, 300, &win, &ctx);
 478    XMapWindow(dpy, win);
 479    glXMakeCurrent(dpy, win, ctx);
 480
 481    if (printInfo) {
 482       printf("GL_RENDERER   = %s\n", (char *) glGetString(GL_RENDERER));
 483       printf("GL_VERSION    = %s\n", (char *) glGetString(GL_VERSION));
 484       printf("GL_VENDOR     = %s\n", (char *) glGetString(GL_VENDOR));
 485       printf("GL_EXTENSIONS = %s\n", (char *) glGetString(GL_EXTENSIONS));
 486    }
 487
 488    init();
 489
 490    event_loop(dpy, win);
 491
 492    glXDestroyContext(dpy, ctx);
 493    XDestroyWindow(dpy, win);
 494    XCloseDisplay(dpy);
 495
 496    return 0;
 497 }