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 #ifdef __VMS
  57    (void) gettimeofday(&tv, NULL );
  58 #else
  59    struct timezone tz;
  60    (void) gettimeofday(&tv, &tz);
  61 #endif
  62    return (int) tv.tv_sec;
  63 }
  64
  65 #else /*BENCHMARK*/
  66
  67 /* dummy */
  68 static int
  69 current_time(void)
  70 {
  71    return 0;
  72 }
  73
  74 #endif /*BENCHMARK*/
  75
  76
  77
  78 #ifndef M_PI
  79 #define M_PI 3.14159265
  80 #endif
  81
  82
  83 static GLfloat view_rotx = 20.0, view_roty = 30.0, view_rotz = 0.0;
  84 static GLint gear1, gear2, gear3;
  85 static GLfloat angle = 0.0;
  86
  87
  88 /*
  89  *
  90  *  Draw a gear wheel.  You'll probably want to call this function when
  91  *  building a display list since we do a lot of trig here.
  92  *
  93  *  Input:  inner_radius - radius of hole at center
  94  *          outer_radius - radius at center of teeth
  95  *          width - width of gear
  96  *          teeth - number of teeth
  97  *          tooth_depth - depth of tooth
  98  */
  99 static void
 100 gear(GLfloat inner_radius, GLfloat outer_radius, GLfloat width,
 101      GLint teeth, GLfloat tooth_depth)
 102 {
 103    GLint i;
 104    GLfloat r0, r1, r2;
 105    GLfloat angle, da;
 106    GLfloat u, v, len;
 107
 108    r0 = inner_radius;
 109    r1 = outer_radius - tooth_depth / 2.0;
 110    r2 = outer_radius + tooth_depth / 2.0;
 111
 112    da = 2.0 * M_PI / teeth / 4.0;
 113
 114    glShadeModel(GL_FLAT);
 115
 116    glNormal3f(0.0, 0.0, 1.0);
 117
 118    /* draw front face */
 119    glBegin(GL_QUAD_STRIP);
 120    for (i = 0; i <= teeth; i++) {
 121       angle = i * 2.0 * M_PI / teeth;
 122       glVertex3f(r0 * cos(angle), r0 * sin(angle), width * 0.5);
 123       glVertex3f(r1 * cos(angle), r1 * sin(angle), width * 0.5);
 124       if (i < teeth) {
 125          glVertex3f(r0 * cos(angle), r0 * sin(angle), width * 0.5);
 126          glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
 127                     width * 0.5);
 128       }
 129    }
 130    glEnd();
 131
 132    /* draw front sides of teeth */
 133    glBegin(GL_QUADS);
 134    da = 2.0 * M_PI / teeth / 4.0;
 135    for (i = 0; i < teeth; i++) {
 136       angle = i * 2.0 * M_PI / teeth;
 137
 138       glVertex3f(r1 * cos(angle), r1 * sin(angle), width * 0.5);
 139       glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), width * 0.5);
 140       glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da),
 141                  width * 0.5);
 142       glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
 143                  width * 0.5);
 144    }
 145    glEnd();
 146
 147    glNormal3f(0.0, 0.0, -1.0);
 148
 149    /* draw back face */
 150    glBegin(GL_QUAD_STRIP);
 151    for (i = 0; i <= teeth; i++) {
 152       angle = i * 2.0 * M_PI / teeth;
 153       glVertex3f(r1 * cos(angle), r1 * sin(angle), -width * 0.5);
 154       glVertex3f(r0 * cos(angle), r0 * sin(angle), -width * 0.5);
 155       if (i < teeth) {
 156          glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
 157                     -width * 0.5);
 158          glVertex3f(r0 * cos(angle), r0 * sin(angle), -width * 0.5);
 159       }
 160    }
 161    glEnd();
 162
 163    /* draw back sides of teeth */
 164    glBegin(GL_QUADS);
 165    da = 2.0 * M_PI / teeth / 4.0;
 166    for (i = 0; i < teeth; i++) {
 167       angle = i * 2.0 * M_PI / teeth;
 168
 169       glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
 170                  -width * 0.5);
 171       glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da),
 172                  -width * 0.5);
 173       glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), -width * 0.5);
 174       glVertex3f(r1 * cos(angle), r1 * sin(angle), -width * 0.5);
 175    }
 176    glEnd();
 177
 178    /* draw outward faces of teeth */
 179    glBegin(GL_QUAD_STRIP);
 180    for (i = 0; i < teeth; i++) {
 181       angle = i * 2.0 * M_PI / teeth;
 182
 183       glVertex3f(r1 * cos(angle), r1 * sin(angle), width * 0.5);
 184       glVertex3f(r1 * cos(angle), r1 * sin(angle), -width * 0.5);
 185       u = r2 * cos(angle + da) - r1 * cos(angle);
 186       v = r2 * sin(angle + da) - r1 * sin(angle);
 187       len = sqrt(u * u + v * v);
 188       u /= len;
 189       v /= len;
 190       glNormal3f(v, -u, 0.0);
 191       glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), width * 0.5);
 192       glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), -width * 0.5);
 193       glNormal3f(cos(angle), sin(angle), 0.0);
 194       glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da),
 195                  width * 0.5);
 196       glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da),
 197                  -width * 0.5);
 198       u = r1 * cos(angle + 3 * da) - r2 * cos(angle + 2 * da);
 199       v = r1 * sin(angle + 3 * da) - r2 * sin(angle + 2 * da);
 200       glNormal3f(v, -u, 0.0);
 201       glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
 202                  width * 0.5);
 203       glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da),
 204                  -width * 0.5);
 205       glNormal3f(cos(angle), sin(angle), 0.0);
 206    }
 207
 208    glVertex3f(r1 * cos(0), r1 * sin(0), width * 0.5);
 209    glVertex3f(r1 * cos(0), r1 * sin(0), -width * 0.5);
 210
 211    glEnd();
 212
 213    glShadeModel(GL_SMOOTH);
 214
 215    /* draw inside radius cylinder */
 216    glBegin(GL_QUAD_STRIP);
 217    for (i = 0; i <= teeth; i++) {
 218       angle = i * 2.0 * M_PI / teeth;
 219       glNormal3f(-cos(angle), -sin(angle), 0.0);
 220       glVertex3f(r0 * cos(angle), r0 * sin(angle), -width * 0.5);
 221       glVertex3f(r0 * cos(angle), r0 * sin(angle), width * 0.5);
 222    }
 223    glEnd();
 224 }
 225
 226
 227 static void
 228 draw(void)
 229 {
 230    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 231
 232    glPushMatrix();
 233    glRotatef(view_rotx, 1.0, 0.0, 0.0);
 234    glRotatef(view_roty, 0.0, 1.0, 0.0);
 235    glRotatef(view_rotz, 0.0, 0.0, 1.0);
 236
 237    glPushMatrix();
 238    glTranslatef(-3.0, -2.0, 0.0);
 239    glRotatef(angle, 0.0, 0.0, 1.0);
 240    glCallList(gear1);
 241    glPopMatrix();
 242
 243    glPushMatrix();
 244    glTranslatef(3.1, -2.0, 0.0);
 245    glRotatef(-2.0 * angle - 9.0, 0.0, 0.0, 1.0);
 246    glCallList(gear2);
 247    glPopMatrix();
 248
 249    glPushMatrix();
 250    glTranslatef(-3.1, 4.2, 0.0);
 251    glRotatef(-2.0 * angle - 25.0, 0.0, 0.0, 1.0);
 252    glCallList(gear3);
 253    glPopMatrix();
 254
 255    glPopMatrix();
 256 }
 257
 258
 259 /* new window size or exposure */
 260 static void
 261 reshape(int width, int height)
 262 {
 263    GLfloat h = (GLfloat) height / (GLfloat) width;
 264
 265    glViewport(0, 0, (GLint) width, (GLint) height);
 266    glMatrixMode(GL_PROJECTION);
 267    glLoadIdentity();
 268    glFrustum(-1.0, 1.0, -h, h, 5.0, 60.0);
 269    glMatrixMode(GL_MODELVIEW);
 270    glLoadIdentity();
 271    glTranslatef(0.0, 0.0, -40.0);
 272 }
 273
 274
 275 static void
 276 init(void)
 277 {
 278    static GLfloat pos[4] = { 5.0, 5.0, 10.0, 0.0 };
 279    static GLfloat red[4] = { 0.8, 0.1, 0.0, 1.0 };
 280    static GLfloat green[4] = { 0.0, 0.8, 0.2, 1.0 };
 281    static GLfloat blue[4] = { 0.2, 0.2, 1.0, 1.0 };
 282
 283    glLightfv(GL_LIGHT0, GL_POSITION, pos);
 284    glEnable(GL_CULL_FACE);
 285    glEnable(GL_LIGHTING);
 286    glEnable(GL_LIGHT0);
 287    glEnable(GL_DEPTH_TEST);
 288
 289    /* make the gears */
 290    gear1 = glGenLists(1);
 291    glNewList(gear1, GL_COMPILE);
 292    glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, red);
 293    gear(1.0, 4.0, 1.0, 20, 0.7);
 294    glEndList();
 295
 296    gear2 = glGenLists(1);
 297    glNewList(gear2, GL_COMPILE);
 298    glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, green);
 299    gear(0.5, 2.0, 2.0, 10, 0.7);
 300    glEndList();
 301
 302    gear3 = glGenLists(1);
 303    glNewList(gear3, GL_COMPILE);
 304    glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, blue);
 305    gear(1.3, 2.0, 0.5, 10, 0.7);
 306    glEndList();
 307
 308    glEnable(GL_NORMALIZE);
 309 }
 310
 311
 312 /*
 313  * Create an RGB, double-buffered window.
 314  * Return the window and context handles.
 315  */
 316 static void
 317 make_window( Display *dpy, const char *name,
 318              int x, int y, int width, int height,
 319              Window *winRet, GLXContext *ctxRet)
 320 {
 321    int attrib[] = { GLX_RGBA,
 322                     GLX_RED_SIZE, 1,
 323                     GLX_GREEN_SIZE, 1,
 324                     GLX_BLUE_SIZE, 1,
 325                     GLX_DOUBLEBUFFER,
 326                     GLX_DEPTH_SIZE, 1,
 327                     None };
 328    int scrnum;
 329    XSetWindowAttributes attr;
 330    unsigned long mask;
 331    Window root;
 332    Window win;
 333    GLXContext ctx;
 334    XVisualInfo *visinfo;
 335
 336    scrnum = DefaultScreen( dpy );
 337    root = RootWindow( dpy, scrnum );
 338
 339    visinfo = glXChooseVisual( dpy, scrnum, attrib );
 340    if (!visinfo) {
 341       printf("Error: couldn't get an RGB, Double-buffered visual\n");
 342       exit(1);
 343    }
 344
 345    /* window attributes */
 346    attr.background_pixel = 0;
 347    attr.border_pixel = 0;
 348    attr.colormap = XCreateColormap( dpy, root, visinfo->visual, AllocNone);
 349    attr.event_mask = StructureNotifyMask | ExposureMask | KeyPressMask;
 350    mask = CWBackPixel | CWBorderPixel | CWColormap | CWEventMask;
 351
 352    win = XCreateWindow( dpy, root, 0, 0, width, height,
 353                         0, visinfo->depth, InputOutput,
 354                         visinfo->visual, mask, &attr );
 355
 356    /* set hints and properties */
 357    {
 358       XSizeHints sizehints;
 359       sizehints.x = x;
 360       sizehints.y = y;
 361       sizehints.width  = width;
 362       sizehints.height = height;
 363       sizehints.flags = USSize | USPosition;
 364       XSetNormalHints(dpy, win, &sizehints);
 365       XSetStandardProperties(dpy, win, name, name,
 366                               None, (char **)NULL, 0, &sizehints);
 367    }
 368
 369    ctx = glXCreateContext( dpy, visinfo, NULL, True );
 370    if (!ctx) {
 371       printf("Error: glXCreateContext failed\n");
 372       exit(1);
 373    }
 374
 375    XFree(visinfo);
 376
 377    *winRet = win;
 378    *ctxRet = ctx;
 379 }
 380
 381
 382 static void
 383 event_loop(Display *dpy, Window win)
 384 {
 385    while (1) {
 386       while (XPending(dpy) > 0) {
 387          XEvent event;
 388          XNextEvent(dpy, &event);
 389          switch (event.type) {
 390          case Expose:
 391             /* we'll redraw below */
 392             break;
 393          case ConfigureNotify:
 394             reshape(event.xconfigure.width, event.xconfigure.height);
 395             break;
 396          case KeyPress:
 397             {
 398                char buffer[10];
 399                int r, code;
 400                code = XLookupKeysym(&event.xkey, 0);
 401                if (code == XK_Left) {
 402                   view_roty += 5.0;
 403                }
 404                else if (code == XK_Right) {
 405                   view_roty -= 5.0;
 406                }
 407                else if (code == XK_Up) {
 408                   view_rotx += 5.0;
 409                }
 410                else if (code == XK_Down) {
 411                   view_rotx -= 5.0;
 412                }
 413                else {
 414                   r = XLookupString(&event.xkey, buffer, sizeof(buffer),
 415                                     NULL, NULL);
 416                   if (buffer[0] == 27) {
 417                      /* escape */
 418                      return;
 419                   }
 420                }
 421             }
 422          }
 423       }
 424
 425       /* next frame */
 426       angle += 2.0;
 427
 428       draw();
 429       glXSwapBuffers(dpy, win);
 430
 431       /* calc framerate */
 432       {
 433          static int t0 = -1;
 434          static int frames = 0;
 435          int t = current_time();
 436
 437          if (t0 < 0)
 438             t0 = t;
 439
 440          frames++;
 441
 442          if (t - t0 >= 5.0) {
 443             GLfloat seconds = t - t0;
 444             GLfloat fps = frames / seconds;
 445             printf("%d frames in %3.1f seconds = %6.3f FPS\n", frames, seconds,
 446                    fps);
 447             t0 = t;
 448             frames = 0;
 449          }
 450       }
 451    }
 452 }
 453
 454
 455 int
 456 main(int argc, char *argv[])
 457 {
 458    Display *dpy;
 459    Window win;
 460    GLXContext ctx;
 461    char *dpyName = ":0";
 462    GLboolean printInfo = GL_FALSE;
 463    int i;
 464
 465    for (i = 1; i < argc; i++) {
 466       if (strcmp(argv[i], "-display") == 0) {
 467          dpyName = argv[i+1];
 468          i++;
 469       }
 470       else if (strcmp(argv[i], "-info") == 0) {
 471          printInfo = GL_TRUE;
 472       }
 473    }
 474
 475    dpy = XOpenDisplay(dpyName);
 476    if (!dpy) {
 477       printf("Error: couldn't open display %s\n", dpyName);
 478       return -1;
 479    }
 480
 481    make_window(dpy, "glxgears", 0, 0, 300, 300, &win, &ctx);
 482    XMapWindow(dpy, win);
 483    glXMakeCurrent(dpy, win, ctx);
 484
 485    if (printInfo) {
 486       printf("GL_RENDERER   = %s\n", (char *) glGetString(GL_RENDERER));
 487       printf("GL_VERSION    = %s\n", (char *) glGetString(GL_VERSION));
 488       printf("GL_VENDOR     = %s\n", (char *) glGetString(GL_VENDOR));
 489       printf("GL_EXTENSIONS = %s\n", (char *) glGetString(GL_EXTENSIONS));
 490    }
 491
 492    init();
 493
 494    event_loop(dpy, win);
 495
 496    glXDestroyContext(dpy, ctx);
 497    XDestroyWindow(dpy, win);
 498    XCloseDisplay(dpy);
 499
 500    return 0;
 501 }