さまざまな言語に対応するゲームプラットフォーム「Simple DirectMedia Layer」

521 main(int argc, char *argv[])
522 {
523    /* Initialize the SDL library */
524    if ( SDL_Init(SDL_INIT_AUDIO|SDL_INIT_VIDEO) < 0 ) {
525       fprintf(stderr, "Couldn't initialize SDL: %s¥n",
                  SDL_GetError());
526       exit(2);
527    }
528    atexit(SDL_Quit);
529
530    /* Open the audio device */
531    if ( Mix_OpenAudio(11025, AUDIO_U8, 1, 512) < 0 ) {
532       fprintf(stderr,
533       "Warning: Couldn't set 11025 Hz 8-bit audio¥n-
           Reason: %s¥n",
534       SDL_GetError());
535    }
536
537    /* Open the display device */
538    screen = SDL_SetVideoMode(640, 480, 0,
          SDL_SWSURFACE|SDL_FULLSCREEN);
539    if ( screen == NULL ) {
540       fprintf(stderr, "Couldn't set 640x480 video mode: %s¥n",
541       SDL_GetError());
542       exit(2);
543    }
544
545    /* Initialize the random number generator */
546    srand(time(NULL));
547
548    /* Load the music and artwork */
549    if ( LoadData() ) {
550       /* Run the game */
551       RunGame();
552
553       /* Free the music and artwork */
554       FreeData();
555    }
556
557    /* Quit */
558    Mix_CloseAudio();
559    exit(0);
560 }

301 void RunGame(void)
302 {
303    int i, j;
304    SDL_Event event;
305    Uint8 *keys;
306
307    /* Paint the background */
308    numupdates = 0;
309    for ( i=0; i<screen->w; i += background->w ) {
310       SDL_Rect dst;
311
312       dst.x = i;
313       dst.y = 0;
314       dst.w = background->w;
315       dst.h = background->h;
316       SDL_BlitSurface(background, NULL, screen, &dst);
317    }
318    SDL_UpdateRect(screen, 0, 0, 0, 0);

319
320    /* Initialize the objects */
321    // . . .
333    CreateAlien();
334    DrawObject(&aliens[0]);
335    UpdateScreen();
336
337    while ( player.alive ) {
338       /* Wait for the next frame */
339       WaitFrame();
340
341       /* Poll input queue, run keyboard loop */
342       while ( SDL_PollEvent(&event) ) {
343          if ( event.type == SDL_QUIT )
344             return;
345       }
346       keys = SDL_GetKeyState(NULL);
347
348       /* Erase everything from the screen */
349       // . . .
366       /* Decrement the lifetime of the explosions */
367       // . . .
373       /* Create new aliens */
374       if ( (rand()%ALIEN_ODDS) == 0 ) {
375          CreateAlien();
376       }
377
378       /* Create new shots */
379       if ( ! reloading ) {
380          if ( keys[SDLK_SPACE] == SDL_PRESSED ) {
381             for ( i=0; i<MAX_SHOTS; ++i ) {
382                if ( ! shots[i].alive ) {
383                   break;
384                }
385             }
386             if ( i != MAX_SHOTS ) {
387                shots[i].x = player.x +
388                   (player.image->w-shots[i].image->w)/2;
389                   shots[i].y = player.y -
390                      shots[i].image->h;
391                   shots[i].alive = 1;
392                   Mix_PlayChannel(SHOT_WAV,
393                      sounds[SHOT_WAV], 0);
394             }
395          }
396       }

397        reloading = (keys[SDLK_SPACE] == SDL_PRESSED);
398
399       /* Move the player */
400       //. . .
415       /* Move the aliens and the shots */
416       // . . .
443
444       /* Detect collisions */
445          for ( j=0; j<MAX_SHOTS; ++j ) {
446          for ( i=0; i<MAX_ALIENS; ++i ) {
447          if ( shots[j].alive && aliens[i].alive &&
448                Collide(&shots[j], &aliens[i]) ) {
449             aliens[i].alive = 0;
450             explosions[i].x = aliens[i].x;
451             explosions[i].y = aliens[i].y;
452             explosions[i].alive = EXPLODE_TIME;
453             Mix_PlayChannel(EXPLODE_WAV,
454                sounds[EXPLODE_WAV], 0);
455             shots[j].alive = 0;
456             break;
457          }
458       }
459    }

127    sounds[MUSIC_WAV] = Mix_LoadWAV(DATAFILE("music.wav"));

474       // . . .
475       /* Draw the aliens, shots, player, and explosions */
476       for ( i=0; i<MAX_ALIENS; ++i ) {
477          if ( aliens[i].alive ) {
478             DrawObject(&aliens[i]);
479          }
480       }
481       // . . .
494       UpdateScreen();
495
496       /* Loop the music */
498       if ( ! Mix_PlayingMusic() ) {
499          Mix_PlayMusic(music, 0);
500       }
506
507       /* Check for keyboard abort */
508       if ( keys[SDLK_ESCAPE] == SDL_PRESSED ) {
509          player.alive = 0;
510       }
511    }
512
513    /* Wait for the player to finish exploding */
514    while ( Mix_Playing(EXPLODE_WAV) ) {
515       WaitFrame();
516    }
517    Mix_HaltChannel(-1);
518    return;
519 }
520