examples/gl_basic.c

   1 // Copyright 2012 - 2014 Intel Corporation
   2 //
   3 // All rights reserved.
   4 //
   5 // Redistribution and use in source and binary forms, with or without
   6 // modification, are permitted provided that the following conditions are met:
   7 //
   8 // - Redistributions of source code must retain the above copyright notice, this
   9 //   list of conditions and the following disclaimer.
  10 //
  11 // - Redistributions in binary form must reproduce the above copyright notice,
  12 //   this list of conditions and the following disclaimer in the documentation
  13 //   and/or other materials provided with the distribution.
  14 //
  15 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  16 // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17 // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  18 // DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  19 // FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20 // DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  21 // SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  22 // CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  23 // OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  24 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25
  26 /// @file
  27 /// @brief Do some basic OpenGL rendering using Waffle.
  28 ///
  29 /// This example does the following:
  30 ///     1. Dynamically choose the platform and OpenGL API according to
  31 ///        command line arguments.
  32 ///     2. Create a window and OpenGL context.
  33 ///     3. Fill the window with red, then green, then blue, sleeping between
  34 ///        each buffer swap.
  35
  36 #define _POSIX_C_SOURCE 199309L // glibc feature macro for nanosleep.
  37 #define WAFFLE_API_VERSION 0x0106
  38 #define WAFFLE_API_EXPERIMENTAL
  39
  40 #include <assert.h>
  41 #include <getopt.h>
  42 #include <stdarg.h>
  43 #include <stdbool.h>
  44 #include <stdio.h>
  45 #include <stdlib.h>
  46 #include <string.h>
  47 #if !defined(_WIN32)
  48 #include <time.h>
  49 #else
  50 #include <windows.h>
  51 #endif
  52
  53 #ifdef __APPLE__
  54 #    import <Foundation/NSAutoreleasePool.h>
  55 #    import <Appkit/NSApplication.h>
  56
  57 static void
  58 removeXcodeArgs(int *argc, char **argv);
  59 #endif
  60
  61 #include "waffle.h"
  62
  63 static const char *usage_message =
  64     "usage:\n"
  65     "    gl_basic --platform=android|cgl|gbm|glx|wayland|wgl|x11_egl\n"
  66     "             --api=gl|gles1|gles2|gles3\n"
  67     "             [--version=MAJOR.MINOR]\n"
  68     "             [--profile=core|compat|none]\n"
  69     "             [--forward-compatible]\n"
  70     "             [--debug]\n"
  71     "             [--robust]\n"
  72     "             [--resize-window]\n"
  73     "             [--window-size=WIDTHxHEIGHT | --fullscreen]\n"
  74     "\n"
  75     "examples:\n"
  76     "    gl_basic --platform=glx --api=gl\n"
  77     "    gl_basic --platform=x11_egl --api=gl --version=3.2 --profile=core\n"
  78     "    gl_basic --platform=wayland --api=gles3\n"
  79     "\n"
  80     "description:\n"
  81     "    Create a window. Fill it with red, green, then blue.\n"
  82     "\n"
  83     "options:\n"
  84     "    --forward-compatible\n"
  85     "        Create a forward-compatible context.\n"
  86     "\n"
  87     "    --debug\n"
  88     "        Create a debug context.\n"
  89     "\n"
  90     "    --robust\n"
  91     "        Create a robust context.\n"
  92     "\n"
  93     "    --resize-window\n"
  94     "        Resize the window between each draw call.\n"
  95     "\n"
  96     "    --fullscreen\n"
  97     "        Create a fullscreen window.\n"
  98     ;
  99
 100 enum {
 101     OPT_PLATFORM = 1,
 102     OPT_API,
 103     OPT_VERSION,
 104     OPT_PROFILE,
 105     OPT_DEBUG,
 106     OPT_FORWARD_COMPATIBLE,
 107     OPT_ROBUST,
 108     OPT_RESIZE_WINDOW,
 109     OPT_WINDOW_SIZE,
 110     OPT_FULLSCREEN,
 111 };
 112
 113 static const struct option get_opts[] = {
 114     { .name = "platform",       .has_arg = required_argument,     .val = OPT_PLATFORM },
 115     { .name = "api",            .has_arg = required_argument,     .val = OPT_API },
 116     { .name = "version",        .has_arg = required_argument,     .val = OPT_VERSION },
 117     { .name = "profile",        .has_arg = required_argument,     .val = OPT_PROFILE },
 118     { .name = "debug",          .has_arg = no_argument,           .val = OPT_DEBUG },
 119     { .name = "forward-compatible", .has_arg = no_argument,       .val = OPT_FORWARD_COMPATIBLE },
 120     { .name = "robust",         .has_arg = no_argument,           .val = OPT_ROBUST },
 121     { .name = "resize-window",  .has_arg = no_argument,           .val = OPT_RESIZE_WINDOW },
 122     { .name = "window-size",    .has_arg = required_argument,     .val = OPT_WINDOW_SIZE },
 123     { .name = "fullscreen",     .has_arg = no_argument,           .val = OPT_FULLSCREEN },
 124     { 0 },
 125 };
 126
 127 #if defined(__GNUC__)
 128 #define NORETURN __attribute__((noreturn))
 129 #elif defined(_MSC_VER)
 130 #define NORETURN __declspec(noreturn)
 131 #else
 132 #define NORETURN
 133 #endif
 134
 135 static void NORETURN
 136 error_printf(const char *fmt, ...)
 137 {
 138     va_list ap;
 139
 140     fflush(stdout);
 141
 142     va_start(ap, fmt);
 143     fprintf(stderr, "gl_basic: error: ");
 144     vfprintf(stderr, fmt, ap);
 145     fprintf(stderr, "\n");
 146     va_end(ap);
 147
 148     exit(EXIT_FAILURE);
 149 }
 150
 151 static void NORETURN
 152 usage_error_printf(const char *fmt, ...)
 153 {
 154     fflush(stdout);
 155     fprintf(stderr, "gl_basic: usage error");
 156
 157     if (fmt) {
 158         va_list ap;
 159         va_start(ap, fmt);
 160         fprintf(stderr, ": ");
 161         vfprintf(stderr, fmt, ap);
 162         va_end(ap);
 163     }
 164
 165     fprintf(stderr, "\n");
 166     fprintf(stderr, "\n");
 167     fprintf(stderr, "%s", usage_message);
 168
 169     exit(EXIT_FAILURE);
 170 }
 171
 172 static void
 173 error_waffle(void)
 174 {
 175     const struct waffle_error_info *info = waffle_error_get_info();
 176     const char *code = waffle_error_to_string(info->code);
 177
 178     if (info->message_length > 0)
 179         error_printf("%s: %s", code, info->message);
 180     else
 181         error_printf("%s", code);
 182 }
 183
 184 static void
 185 error_get_gl_symbol(const char *name)
 186 {
 187     error_printf("failed to get function pointer for %s", name);
 188 }
 189
 190 typedef float GLclampf;
 191 typedef unsigned int GLbitfield;
 192 typedef unsigned int GLint;
 193 typedef int GLsizei;
 194 typedef unsigned int GLenum;
 195 typedef void GLvoid;
 196
 197 enum {
 198     // Copied from <GL/gl*.h>.
 199     GL_UNSIGNED_BYTE =    0x00001401,
 200     GL_RGBA =             0x00001908,
 201     GL_COLOR_BUFFER_BIT = 0x00004000,
 202
 203     GL_CONTEXT_FLAGS = 0x821e,
 204     GL_CONTEXT_FLAG_FORWARD_COMPATIBLE_BIT = 0x00000001,
 205     GL_CONTEXT_FLAG_DEBUG_BIT              = 0x00000002,
 206     GL_CONTEXT_FLAG_ROBUST_ACCESS_BIT      = 0x00000004 ,
 207 };
 208
 209 static int window_width = 320;
 210 static int window_height = 240;
 211
 212 #ifndef _WIN32
 213 #define APIENTRY
 214 #else
 215 #ifndef APIENTRY
 216 #define APIENTRY __stdcall
 217 #endif
 218 #endif
 219
 220 static void (APIENTRY *glClearColor)(GLclampf red, GLclampf green, GLclampf blue, GLclampf alpha);
 221 static void (APIENTRY *glClear)(GLbitfield mask);
 222 static GLenum (APIENTRY *glGetError)(void);
 223 static void (APIENTRY *glGetIntegerv)(GLenum pname, GLint *params);
 224 static void (APIENTRY *glReadPixels)(GLint x, GLint y, GLsizei width, GLsizei height,
 225                                      GLenum format, GLenum type, GLvoid* data);
 226 static void (APIENTRY *glViewport)(GLint x, GLint y, GLsizei width, GLsizei height);
 227
 228 /// @brief Command line options.
 229 struct options {
 230     /// @brief One of `WAFFLE_PLATFORM_*`.
 231     int platform;
 232
 233     /// @brief One of `WAFFLE_CONTEXT_OPENGL_*`.
 234     int context_api;
 235
 236     /// @brief One of `WAFFLE_CONTEXT_PROFILE_*` or `WAFFLE_NONE`.
 237     int context_profile;
 238
 239     int context_version;
 240
 241     bool context_forward_compatible;
 242     bool context_debug;
 243     bool context_robust;
 244
 245     bool resize_window;
 246
 247     bool fullscreen;
 248
 249     /// @brief One of `WAFFLE_DL_*`.
 250     int dl;
 251 };
 252
 253 struct enum_map {
 254     int i;
 255     const char *s;
 256 };
 257
 258 static const struct enum_map platform_map[] = {
 259     {WAFFLE_PLATFORM_ANDROID,   "android"       },
 260     {WAFFLE_PLATFORM_CGL,       "cgl",          },
 261     {WAFFLE_PLATFORM_GBM,       "gbm"           },
 262     {WAFFLE_PLATFORM_GLX,       "glx"           },
 263     {WAFFLE_PLATFORM_WAYLAND,   "wayland"       },
 264     {WAFFLE_PLATFORM_WGL,       "wgl"           },
 265     {WAFFLE_PLATFORM_X11_EGL,   "x11_egl"       },
 266     {0,                         0               },
 267 };
 268
 269 static const struct enum_map context_api_map[] = {
 270     {WAFFLE_CONTEXT_OPENGL,         "gl"        },
 271     {WAFFLE_CONTEXT_OPENGL_ES1,     "gles1"     },
 272     {WAFFLE_CONTEXT_OPENGL_ES2,     "gles2"     },
 273     {WAFFLE_CONTEXT_OPENGL_ES3,     "gles3"     },
 274     {0,                             0           },
 275 };
 276
 277 /// @brief Translate string to `enum waffle_enum`.
 278 ///
 279 /// @param self is a list of map items. The last item must be zero-filled.
 280 /// @param result is altered only if @a s if found.
 281 /// @return true if @a s was found in @a map.
 282 static bool
 283 enum_map_translate_str(
 284         const struct enum_map *self,
 285         const char *s,
 286         int *result)
 287 {
 288     for (const struct enum_map *i = self; i->i != 0; ++i) {
 289         if (!strncmp(s, i->s, strlen(i->s) + 1)) {
 290             *result = i->i;
 291             return true;
 292         }
 293     }
 294
 295     return false;
 296 }
 297
 298 /// @return true on success.
 299 static bool
 300 parse_args(int argc, char *argv[], struct options *opts)
 301 {
 302     bool ok;
 303     bool loop_get_opt = true;
 304     bool found_window_size = false;
 305
 306 #ifdef __APPLE__
 307     removeXcodeArgs(&argc, argv);
 308 #endif
 309
 310     // Set some context attrs to invalid values.
 311     opts->context_profile = -1;
 312     opts->context_version = -1;
 313
 314     while (loop_get_opt) {
 315         int opt = getopt_long(argc, argv, "", get_opts, NULL);
 316         switch (opt) {
 317             case -1:
 318                 loop_get_opt = false;
 319                 break;
 320             case '?':
 321                 goto error_unrecognized_arg;
 322             case OPT_PLATFORM:
 323                 ok = enum_map_translate_str(platform_map, optarg,
 324                                             &opts->platform);
 325                 if (!ok) {
 326                     usage_error_printf("'%s' is not a valid platform",
 327                                        optarg);
 328                 }
 329                 break;
 330             case OPT_API:
 331                 ok = enum_map_translate_str(context_api_map, optarg,
 332                                             &opts->context_api);
 333                 if (!ok) {
 334                     usage_error_printf("'%s' is not a valid API for an OpenGL "
 335                                        "context", optarg);
 336                 }
 337                 break;
 338             case OPT_VERSION: {
 339                 int major;
 340                 int minor;
 341                 int match_count;
 342
 343                 match_count = sscanf(optarg, "%d.%d", &major, &minor);
 344                 if (match_count != 2) {
 345                     usage_error_printf("'%s' is not a valid OpenGL version",
 346                                        optarg);
 347                 }
 348                 opts->context_version = 10 * major + minor;
 349                 break;
 350             }
 351             case OPT_PROFILE:
 352                 if (strcmp(optarg, "none") == 0) {
 353                     opts->context_profile = WAFFLE_NONE;
 354                 } else if (strcmp(optarg, "core") == 0) {
 355                     opts->context_profile = WAFFLE_CONTEXT_CORE_PROFILE;
 356                 } else if (strcmp(optarg, "compat") == 0) {
 357                     opts->context_profile = WAFFLE_CONTEXT_COMPATIBILITY_PROFILE;
 358                 } else {
 359                     usage_error_printf("'%s' is not a valid OpenGL profile",
 360                                        optarg);
 361                 }
 362                 break;
 363             case OPT_FORWARD_COMPATIBLE:
 364                 opts->context_forward_compatible = true;
 365                 break;
 366             case OPT_DEBUG:
 367                 opts->context_debug = true;
 368                 break;
 369             case OPT_ROBUST:
 370                 opts->context_robust = true;
 371                 break;
 372             case OPT_RESIZE_WINDOW:
 373                 opts->resize_window = true;
 374                 break;
 375             case OPT_WINDOW_SIZE: {
 376                 int match_count;
 377                 match_count = sscanf(optarg, "%dx%d", &window_width, &window_height);
 378                 if (match_count != 2) {
 379                     usage_error_printf("'%s' is not a valid window geometry",
 380                                        optarg);
 381                 }
 382                 found_window_size = true;
 383                 break;
 384             }
 385             case OPT_FULLSCREEN:
 386                 opts->fullscreen = true;
 387                 break;
 388             default:
 389                 abort();
 390                 loop_get_opt = false;
 391                 break;
 392         }
 393     }
 394
 395     if (optind < argc) {
 396         goto error_unrecognized_arg;
 397     }
 398
 399     if (!opts->platform) {
 400         usage_error_printf("--platform is required");
 401     }
 402
 403     if (!opts->context_api) {
 404         usage_error_printf("--api is required");
 405     }
 406
 407     if (opts->fullscreen && found_window_size) {
 408         usage_error_printf("--fullscreen and --window-size are mutually "
 409                            "exclusive options");
 410     }
 411
 412     // Set dl.
 413     switch (opts->context_api) {
 414         case WAFFLE_CONTEXT_OPENGL:     opts->dl = WAFFLE_DL_OPENGL;      break;
 415         case WAFFLE_CONTEXT_OPENGL_ES1: opts->dl = WAFFLE_DL_OPENGL_ES1;  break;
 416         case WAFFLE_CONTEXT_OPENGL_ES2: opts->dl = WAFFLE_DL_OPENGL_ES2;  break;
 417         case WAFFLE_CONTEXT_OPENGL_ES3: opts->dl = WAFFLE_DL_OPENGL_ES3;  break;
 418         default:
 419             abort();
 420             break;
 421     }
 422
 423     return true;
 424
 425 error_unrecognized_arg:
 426     usage_error_printf("unrecognized option '%s'", optarg);
 427 }
 428
 429 // The rules that dictate how to properly query a GL symbol are complex. The
 430 // rules depend on the OS, on the winsys API, and even on the particular driver
 431 // being used. The rules differ between EGL 1.4 and EGL 1.5; differ between
 432 // Linux, Windows, and Mac; and differ between Mesa and Mali.
 433 //
 434 // This function hides that complexity with a naive heuristic: try, then try
 435 // again.
 436 static void *
 437 get_gl_symbol(const struct options *opts, const char *name)
 438 {
 439     void *sym = NULL;
 440
 441     if (waffle_dl_can_open(opts->dl)) {
 442         sym = waffle_dl_sym(opts->dl, name);
 443     }
 444
 445     if (!sym) {
 446         sym = waffle_get_proc_address(name);
 447     }
 448
 449     return sym;
 450 }
 451
 452 static bool
 453 draw(struct waffle_window *window, bool resize)
 454 {
 455     bool ok;
 456     unsigned char *colors;
 457     int width = window_width;
 458     int height = window_height;
 459
 460 #if !defined(_WIN32)
 461     static const struct timespec sleep_time = {
 462          // 0.5 sec
 463         .tv_sec = 0,
 464         .tv_nsec = 500000000,
 465     };
 466 #endif
 467
 468     for (int i = 0; i < 3; ++i) {
 469         switch (i) {
 470             case 0: glClearColor(1, 0, 0, 1); break;
 471             case 1: glClearColor(0, 1, 0, 1); break;
 472             case 2: glClearColor(0, 0, 1, 1); break;
 473             case 3: abort(); break;
 474         }
 475
 476         if (resize) {
 477             width = (i + 2) * 40;
 478             height = width;
 479             waffle_window_resize(window, width, height);
 480             glViewport(0, 0, width, height);
 481         }
 482
 483         glClear(GL_COLOR_BUFFER_BIT);
 484
 485         colors = calloc(width * height * 4, sizeof(*colors));
 486         glReadPixels(0, 0,
 487                      width, height,
 488                      GL_RGBA, GL_UNSIGNED_BYTE,
 489                      colors);
 490         for (int j = 0; j < width * height * 4; j += 4) {
 491            if ((colors[j]   != (i == 0 ? 0xff : 0)) ||
 492                (colors[j+1] != (i == 1 ? 0xff : 0)) ||
 493                (colors[j+2] != (i == 2 ? 0xff : 0)) ||
 494                (colors[j+3] != 0xff)) {
 495               fprintf(stderr, "glReadPixels returned unexpected result\n");
 496               break;
 497            }
 498         }
 499         free(colors);
 500
 501         if (i == 0) {
 502             ok = waffle_window_show(window);
 503             if (!ok)
 504                 return false;
 505         }
 506
 507         ok = waffle_window_swap_buffers(window);
 508         if (!ok)
 509             return false;
 510
 511 #if !defined(_WIN32)
 512         nanosleep(&sleep_time, NULL);
 513 #else
 514         Sleep(500);
 515 #endif
 516     }
 517
 518     return true;
 519 }
 520
 521 #ifdef __APPLE__
 522
 523 static NSAutoreleasePool *pool;
 524
 525 static void
 526 cocoa_init(void)
 527 {
 528     // From the NSApplication Class Reference:
 529     //     [...] if you do need to use Cocoa classes within the main()
 530     //     function itself (other than to load nib files or to instantiate
 531     //     NSApplication), you should create an autorelease pool before using
 532     //     the classes and then release the pool when you’re done.
 533     pool = [[NSAutoreleasePool alloc] init];
 534
 535     // From the NSApplication Class Reference:
 536     //     The sharedApplication class method initializes the display
 537     //     environment and connects your program to the window server and the
 538     //     display server.
 539     //
 540     // It also creates the singleton NSApp if it does not yet exist.
 541     [NSApplication sharedApplication];
 542 }
 543
 544 static void
 545 cocoa_finish(void)
 546 {
 547     [pool drain];
 548 }
 549
 550 static void
 551 removeArg(int index, int *argc, char **argv)
 552 {
 553     --*argc;
 554     for (; index < *argc; ++index)
 555         argv[index] = argv[index + 1];
 556 }
 557
 558 static void
 559 removeXcodeArgs(int *argc, char **argv)
 560 {
 561     // Xcode sometimes adds additional arguments.
 562     for (int i = 1; i < *argc; )
 563     {
 564         if (strcmp(argv[i], "-NSDocumentRevisionsDebugMode") == 0 ||
 565             strcmp(argv[i], "-ApplePersistenceIgnoreState" ) == 0)
 566         {
 567             removeArg(i, argc, argv);
 568             removeArg(i, argc, argv);
 569         } else
 570             ++i;
 571     }
 572 }
 573
 574 #endif // __APPLE__
 575
 576 #ifdef __native_client__
 577 #include "ppapi_simple/ps_main.h"
 578 //
 579 // We need to rename main() for native client
 580 // because ppapi_simple already defines main().
 581 //
 582 int basic_test_main(int argc, char **argv);
 583 PPAPI_SIMPLE_REGISTER_MAIN(basic_test_main)
 584 int
 585 basic_test_main(int argc, char **argv)
 586 #else
 587 int
 588 main(int argc, char **argv)
 589 #endif
 590 {
 591     bool ok;
 592     int i;
 593
 594     struct options opts = {0};
 595
 596     int32_t init_attrib_list[3];
 597     int32_t config_attrib_list[64];
 598     intptr_t window_attrib_list[5];
 599
 600     struct waffle_display *dpy;
 601     struct waffle_config *config;
 602     struct waffle_context *ctx;
 603     struct waffle_window *window;
 604
 605     GLint context_flags = 0;
 606
 607     #ifdef __APPLE__
 608         cocoa_init();
 609     #endif
 610
 611     #ifdef __native_client__
 612         // Fixed arguments for native client.
 613         opts.context_api = WAFFLE_CONTEXT_OPENGL_ES2;
 614         opts.platform = WAFFLE_PLATFORM_NACL;
 615         opts.dl = WAFFLE_DL_OPENGL_ES2;
 616         opts.context_profile = WAFFLE_NONE;
 617         opts.context_version = -1;
 618     #else
 619     ok = parse_args(argc, argv, &opts);
 620     if (!ok)
 621         exit(EXIT_FAILURE);
 622     #endif
 623
 624     i = 0;
 625     init_attrib_list[i++] = WAFFLE_PLATFORM;
 626     init_attrib_list[i++] = opts.platform;
 627     init_attrib_list[i++] = WAFFLE_NONE;
 628
 629     ok = waffle_init(init_attrib_list);
 630     if (!ok)
 631         error_waffle();
 632
 633     dpy = waffle_display_connect(NULL);
 634     if (!dpy)
 635         error_waffle();
 636
 637     if (!waffle_display_supports_context_api(dpy, opts.context_api)) {
 638         error_printf("Display does not support %s",
 639                      waffle_enum_to_string(opts.context_api));
 640     }
 641
 642     glClear = get_gl_symbol(&opts, "glClear");
 643     if (!glClear)
 644         error_get_gl_symbol("glClear");
 645
 646     glClearColor = get_gl_symbol(&opts, "glClearColor");
 647     if (!glClearColor)
 648         error_get_gl_symbol("glClearColor");
 649
 650     glGetError = get_gl_symbol(&opts, "glGetError");
 651     if (!glGetError)
 652         error_get_gl_symbol("glGetError");
 653
 654     glGetIntegerv = get_gl_symbol(&opts, "glGetIntegerv");
 655     if (!glGetIntegerv)
 656         error_get_gl_symbol("glGetIntegerv");
 657
 658     glReadPixels = get_gl_symbol(&opts, "glReadPixels");
 659     if (!glReadPixels)
 660         error_get_gl_symbol("glReadPixels");
 661
 662     glViewport = get_gl_symbol(&opts, "glViewport");
 663     if (!glViewport)
 664         error_get_gl_symbol("glViewport");
 665
 666     i = 0;
 667     config_attrib_list[i++] = WAFFLE_CONTEXT_API;
 668     config_attrib_list[i++] = opts.context_api;
 669
 670     if (opts.context_profile != -1) {
 671         config_attrib_list[i++] = WAFFLE_CONTEXT_PROFILE;
 672         config_attrib_list[i++] = opts.context_profile;
 673     }
 674
 675     if (opts.context_version != -1) {
 676         config_attrib_list[i++] = WAFFLE_CONTEXT_MAJOR_VERSION;
 677         config_attrib_list[i++] = opts.context_version / 10;
 678         config_attrib_list[i++] = WAFFLE_CONTEXT_MINOR_VERSION;
 679         config_attrib_list[i++] = opts.context_version % 10;
 680     }
 681
 682     if (opts.context_forward_compatible) {
 683         config_attrib_list[i++] = WAFFLE_CONTEXT_FORWARD_COMPATIBLE;
 684         config_attrib_list[i++] = true;
 685     }
 686
 687     if (opts.context_debug) {
 688         config_attrib_list[i++] = WAFFLE_CONTEXT_DEBUG;
 689         config_attrib_list[i++] = true;
 690     }
 691
 692     if (opts.context_robust) {
 693         config_attrib_list[i++] = WAFFLE_CONTEXT_ROBUST_ACCESS,
 694         config_attrib_list[i++] = true;
 695     }
 696
 697     config_attrib_list[i++] = WAFFLE_RED_SIZE;
 698     config_attrib_list[i++] = 8;
 699     config_attrib_list[i++] = WAFFLE_GREEN_SIZE;
 700     config_attrib_list[i++] = 8;
 701     config_attrib_list[i++] = WAFFLE_BLUE_SIZE;
 702     config_attrib_list[i++] = 8;
 703     config_attrib_list[i++] = WAFFLE_ALPHA_SIZE;
 704     config_attrib_list[i++] = 8;
 705     config_attrib_list[i++] = WAFFLE_DOUBLE_BUFFERED;
 706     config_attrib_list[i++] = true;
 707     config_attrib_list[i++] = 0;
 708
 709     config = waffle_config_choose(dpy, config_attrib_list);
 710     if (!config)
 711         error_waffle();
 712
 713     ctx = waffle_context_create(config, NULL);
 714     if (!ctx)
 715         error_waffle();
 716
 717
 718     i = 0;
 719     if (opts.fullscreen) {
 720         window_attrib_list[i++] = WAFFLE_WINDOW_FULLSCREEN;
 721         window_attrib_list[i++] = true;
 722         window_attrib_list[i++] = 0;
 723     } else {
 724         window_attrib_list[i++] = WAFFLE_WINDOW_WIDTH;
 725         window_attrib_list[i++] = window_width;
 726         window_attrib_list[i++] = WAFFLE_WINDOW_HEIGHT;
 727         window_attrib_list[i++] = window_height;
 728         window_attrib_list[i++] = 0;
 729     }
 730
 731     window = waffle_window_create2(config, window_attrib_list);
 732     if (!window)
 733         error_waffle();
 734
 735     ok = waffle_make_current(dpy, window, ctx);
 736     if (!ok)
 737         error_waffle();
 738
 739     if (opts.context_forward_compatible || opts.context_debug) {
 740         glGetIntegerv(GL_CONTEXT_FLAGS, &context_flags);
 741     }
 742
 743     if (glGetError())
 744         error_printf("glGetIntegerv(GL_CONTEXT_FLAGS) failed");
 745
 746     if (opts.context_forward_compatible
 747         && !(context_flags & GL_CONTEXT_FLAG_FORWARD_COMPATIBLE_BIT)) {
 748         error_printf("context is not forward-compatible");
 749     }
 750
 751     if (opts.context_debug
 752         && !(context_flags & GL_CONTEXT_FLAG_DEBUG_BIT)) {
 753         error_printf("context is not a debug context");
 754     }
 755
 756     // Don't verify if the context is robust because that pollutes this simple
 757     // example program with hairy GL logic. The method of verifying if
 758     // a context is robust varies on the combination of context profile,
 759     // context version, and supported extensions.
 760
 761     ok = draw(window, opts.resize_window);
 762     if (!ok)
 763         error_waffle();
 764
 765     ok = waffle_make_current(dpy, NULL, NULL);
 766     if (!ok)
 767         error_waffle();
 768
 769     ok = waffle_window_destroy(window);
 770     if (!ok)
 771         error_waffle();
 772
 773     ok = waffle_context_destroy(ctx);
 774     if (!ok)
 775         error_waffle();
 776
 777     ok = waffle_config_destroy(config);
 778     if (!ok)
 779         error_waffle();
 780
 781     ok = waffle_display_disconnect(dpy);
 782     if (!ok)
 783         error_waffle();
 784
 785     ok = waffle_teardown();
 786     if (!ok)
 787         error_waffle();
 788
 789     #ifdef __APPLE__
 790         cocoa_finish();
 791     #endif
 792
 793     printf("gl_basic: run was successful\n");
 794     return EXIT_SUCCESS;
 795 }