main.c

   1 /* Variations on RockDodger
   2  * Space Rocks copyright (C) 2001 Paul Holt <pad@pcholt.com>
   3  *
   4  * Project fork 2004, Jason Woofenden and Joshua Grams.
   5  * (a whole bunch of modifications and project rename)
   6
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the
   9  * Free Software Foundation; either version 2 of the License, or (at your
  10  * option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  20  */
  21
  22 #include <math.h>
  23 #include <SDL.h>
  24 #include <SDL_image.h>
  25 #include <stdarg.h>
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29
  30 #include "font.h"
  31
  32 #include "args.h"
  33 #include "common.h"
  34 #include "config.h"
  35 #include "dust.h"
  36 #include "file.h"
  37 #include "globals.h"
  38 #include "mt.h"
  39 #include "rocks.h"
  40 #include "score.h"
  41 #include "sprite.h"
  42 #include "sound.h"
  43
  44 // ************************************* VARS
  45 // SDL_Surface global variables
  46 SDL_Surface
  47         *surf_screen,   // Screen
  48         *surf_b_variations, // "variations" banner
  49         *surf_b_on, // "on" banner
  50         *surf_b_rockdodger, // "rockdodger" banner
  51         *surf_b_game,   // Title element "game"
  52         *surf_b_over,   // Title element "over"
  53         *surf_life,     // Indicator of number of ships remaining
  54         *surf_rock[NROCKS],     // THE ROCKS
  55         *surf_font_big; // The big font
  56
  57
  58 font *g_font;
  59
  60 // Structure global variables
  61 struct enginedots edot[MAXENGINEDOTS], *dotptr = edot;
  62 struct bangdots bdot[MAXBANGDOTS], *bdotptr = bdot;
  63
  64 // Other global variables
  65 char topline[1024];
  66 char *initerror = "";
  67
  68 struct ship ship = { SHIP, 0, NULL, XSIZE/2, YSIZE/2, BARRIER_SPEED, 0.0 };
  69
  70 float screendx = BARRIER_SPEED, screendy = 0.0;
  71 float dist_ahead;
  72
  73 // all movement is based on t_frame.
  74 unsigned long frames, start, end;
  75 float t_frame;  // length of this frame (in ticks = 1/20th second)  adjusted for gamespeed
  76 int ms_frame;   // length of this frame (milliseconds)
  77 int ms_end;     // end of this frame (milliseconds)
  78
  79 float gamespeed = 1.00;
  80
  81 int score;
  82
  83 float fadetimer = 0;
  84
  85 int pausedown = 0, paused = 0;
  86
  87 // bangdot start (bd1) and end (bd2) position:
  88 int bd1 = 0, bd2 = 0;
  89
  90 enum states {
  91         TITLE_PAGE,
  92         GAMEPLAY,
  93         DEAD_PAUSE,
  94         GAME_OVER,
  95         HIGH_SCORE_ENTRY,
  96         HIGH_SCORE_DISPLAY
  97 };
  98 enum states state = TITLE_PAGE;
  99 float state_timeout = 600.0;
 100
 101 #define NSEQUENCE 3
 102 char *msgs[2][3] = {
 103         {
 104                 "Press SPACE for normal game",
 105                 "Press '1' for easy game",
 106                 "http://jasonwoof.org/vor"
 107         },
 108         {
 109                 "Press SPACE for easy game",
 110                 "Press '2' for normal game",
 111                 "http://jasonwoof.org/vor"
 112         }
 113 };
 114
 115 int bangdotlife, nbangdots;
 116 Uint16 heatcolor[W*3];
 117
 118 char *data_dir;
 119 extern char *optarg;
 120 extern int optind, opterr, optopt;
 121
 122 #define TO_TICKS(seconds) ((seconds)*20*gamespeed)
 123
 124 // ************************************* FUNCS
 125
 126 void
 127 init_engine_dots() {
 128         int i;
 129         for(i = 0; i<MAXENGINEDOTS; i++) {
 130                 edot[i].active = 0;
 131         }
 132 }
 133
 134 void
 135 new_bang_dots(struct sprite *s)
 136 {
 137         int i, n, x, y;
 138         uint16_t *pixel, c;
 139         uint32_t colorkey;
 140         int row_inc;
 141         double theta, r;
 142         SDL_Surface *img = s->image;
 143
 144         n = 20;
 145         pixel = img->pixels;
 146         row_inc = img->pitch/sizeof(uint16_t) - img->w;
 147         colorkey = img->format->colorkey;
 148
 149         if(SDL_MUSTLOCK(img)) { SDL_LockSurface(img); }
 150
 151         for(i=0; i<n; i++) {
 152                 pixel = img->pixels;
 153                 for(y=0; y<img->h; y++) {
 154                         for(x = 0; x<img->w; x++) {
 155                                 c = *pixel++;
 156                                 if(c && c != colorkey) {
 157                                         theta = frnd()*M_PI*2;
 158                                         r = frnd(); r = 1 - r*r;
 159
 160                                         bdot[bd2].dx = 45*r*cos(theta) + s->dx;
 161                                         bdot[bd2].dy = 45*r*sin(theta) + s->dy;
 162                                         bdot[bd2].x = x + s->x;
 163                                         bdot[bd2].y = y + s->y;
 164                                         //bdot[bd2].c = (i < n-3) ? 0 : c;
 165                                         bdot[bd2].life = frnd() * 99;
 166                                         bdot[bd2].decay = frnd()*3 + 1;
 167                                         bdot[bd2].active = 1;
 168
 169                                         bd2 = (bd2+1) % MAXBANGDOTS;
 170                                 }
 171                                 pixel += row_inc;
 172                         }
 173                 }
 174         }
 175
 176         if(SDL_MUSTLOCK(img)) { SDL_UnlockSurface(img); }
 177 }
 178
 179 void
 180 move_bang_dots(float ticks)
 181 {
 182         int i;
 183         Sprite *hit;
 184
 185         for(i=0; i<MAXBANGDOTS; i++) {
 186                 if(!bdot[i].active) continue;
 187
 188                 // decrement life and maybe kill
 189                 bdot[i].life -= bdot[i].decay * ticks/2.0;
 190                 if(bdot[i].life < 0) { bdot[i].active = 0; continue; }
 191
 192                 // move and clip
 193                 bdot[i].x += (bdot[i].dx - screendx)*ticks;
 194                 bdot[i].y += (bdot[i].dy - screendy)*ticks;
 195                 if(bdot[i].x < 0 || bdot[i].x >= (XSIZE - 0.000001) || bdot[i].y < 0 || bdot[i].y >= (YSIZE - 0.000001)) {
 196                         bdot[i].active = 0;
 197                         continue;
 198                 }
 199
 200                 // check collisions
 201                 if((hit = pixel_collides(bdot[i].x, bdot[i].y))) {
 202                         if(hit->type != SHIP) { // they shouldn't hit the ship, but they do
 203                                 bdot[i].active = 0;
 204                                 hit->dx += ENGINE_DOT_WEIGHT * bdot[i].life * bdot[i].dx / sprite_mass(hit);
 205                                 hit->dy += ENGINE_DOT_WEIGHT * bdot[i].life * bdot[i].dy / sprite_mass(hit);
 206                                 continue;
 207                         }
 208                 }
 209         }
 210 }
 211
 212
 213 void
 214 draw_bang_dots(SDL_Surface *s)
 215 {
 216         int i;
 217         uint16_t *pixels, *pixel, c;
 218         int row_inc = s->pitch/sizeof(uint16_t);
 219
 220         pixels = (uint16_t *) s->pixels;
 221
 222         for(i=0; i<MAXBANGDOTS; i++) {
 223                 if(!bdot[i].active) continue;
 224
 225                 pixel = pixels + row_inc*(int)(bdot[i].y) + (int)(bdot[i].x);
 226                 if(bdot[i].c) c = bdot[i].c; else c = heatcolor[(int)(bdot[i].life)*3];
 227                 *pixel = c;
 228         }
 229 }
 230
 231
 232 void
 233 new_engine_dots(float time_span) {
 234         int dir, i;
 235         int n = time_span * ENGINE_DOTS_PER_TIC;
 236         float a, r;  // angle, random length
 237         float dx, dy;
 238         float hx, hy; // half ship width/height.
 239         static const int s[4] = { 2, 1, 0, 1 };
 240         float time;
 241         float accelh, accelv, past_ship_dx, past_ship_dy;
 242
 243         hx = ship.image->w / 2;
 244         hy = ship.image->h / 2;
 245
 246         for(dir=0; dir<4; dir++) {
 247                 if(!(ship.jets & 1<<dir)) continue;
 248
 249                 for(i = 0; i<n; i++) {
 250                         if(dotptr->active == 0) {
 251                                 a = frnd()*M_PI + (dir-1)*M_PI_2;
 252                                 r = sin(frnd()*M_PI);
 253                                 dx = r * cos(a);
 254                                 dy = r * -sin(a);  // screen y is "backwards".
 255
 256                                 dotptr->active = 1;
 257
 258                                 // dot was created at a random time during the time span
 259                                 time = frnd() * time_span; // this is how long ago
 260
 261                                 // calculate how fast the ship was going when this engine dot was
 262                                 // created (as if it had a smooth acceleration). This is used in
 263                                 // determining the velocity of the dots, but not their starting
 264                                 // location.
 265                                 accelh = ((ship.jets >> 2) & 1) - (ship.jets & 1);
 266                                 accelh *= THRUSTER_STRENGTH * time;
 267                                 past_ship_dx = ship.dx - accelh;
 268                                 accelv = ((ship.jets >> 1) & 1) - ((ship.jets >> 3) & 1);
 269                                 accelv *= THRUSTER_STRENGTH * time;
 270                                 past_ship_dy = ship.dy - accelv;
 271
 272                                 // the starting position (not speed) of the dot is calculated as
 273                                 // though the ship were traveling at a constant speed for this
 274                                 // time_span.
 275                                 dotptr->x = (ship.x - (ship.dx - screendx) * time) + s[dir]*hx;
 276                                 dotptr->y = (ship.y - (ship.dy - screendy) * time) + s[(dir+1)&3]*hy;
 277                                 if(dir&1) {
 278                                         dotptr->dx = past_ship_dx + 2*dx;
 279                                         dotptr->dy = past_ship_dy + 20*dy;
 280                                         dotptr->life = 60 * fabs(dy);
 281                                 } else {
 282                                         dotptr->dx = past_ship_dx + 20*dx;
 283                                         dotptr->dy = past_ship_dy + 2*dy;
 284                                         dotptr->life = 60 * fabs(dx);
 285                                 }
 286
 287                                 // move the dot as though it were created in the past
 288                                 dotptr->x += (dotptr->dx - screendx) * time;
 289                                 dotptr->y += (dotptr->dy - screendy) * time;
 290
 291                                 if(dotptr - edot < MAXENGINEDOTS-1) dotptr++;
 292                                 else dotptr = edot;
 293                         }
 294                 }
 295         }
 296 }
 297
 298 void
 299 move_engine_dots(float ticks) {
 300         int i;
 301         Sprite *hit;
 302
 303         for(i = 0; i<MAXENGINEDOTS; i++) {
 304                 if(!edot[i].active) continue;
 305
 306                 edot[i].x += (edot[i].dx - screendx)*ticks;
 307                 edot[i].y += (edot[i].dy - screendy)*ticks;
 308                 edot[i].life -= t_frame*3;
 309                 if(edot[i].life < 0 || edot[i].x<0 || edot[i].x >= (XSIZE - 0.000001) || edot[i].y < 0 || edot[i].y >= (YSIZE - 0.000001)) {
 310                         edot[i].active = 0;
 311                         continue;
 312                 }
 313
 314                 // check collisions
 315                 if((hit = pixel_collides(edot[i].x, edot[i].y))) {
 316                         if(hit->type != SHIP) { // they shouldn't hit the ship, but they do
 317                                 edot[i].active = 0;
 318                                 hit->dx += ENGINE_DOT_WEIGHT * edot[i].life * edot[i].dx / sprite_mass(hit);
 319                                 hit->dy += ENGINE_DOT_WEIGHT * edot[i].life * edot[i].dy / sprite_mass(hit);
 320                                 continue;
 321                         }
 322                 }
 323         }
 324 }
 325
 326 void
 327 draw_engine_dots(SDL_Surface *s) {
 328         int i;
 329         uint16_t c;
 330         uint16_t *pixels = (uint16_t *) s->pixels;
 331         int row_inc = s->pitch/sizeof(uint16_t);
 332         int heatindex;
 333
 334         for(i = 0; i<MAXENGINEDOTS; i++) {
 335                 if(!edot[i].active) continue;
 336
 337                 heatindex = edot[i].life * 6;
 338                 c = heatindex>3*W ? heatcolor[3*W-1] : heatcolor[heatindex];
 339                 pixels[row_inc*(int)(edot[i].y) + (int)(edot[i].x)] = c;
 340         }
 341 }
 342
 343 void
 344 draw_dots(SDL_Surface *s) {
 345         if(SDL_MUSTLOCK(s)) { SDL_LockSurface(s); }
 346         draw_dust(s);
 347         draw_engine_dots(s);
 348         draw_bang_dots(s);
 349         if(SDL_MUSTLOCK(s)) { SDL_UnlockSurface(s); }
 350 }
 351
 352 SDL_Surface *
 353 load_image(char *filename)
 354 {
 355         SDL_Surface *tmp, *img = NULL;
 356         char *s = add_data_path(filename);
 357         if(s) {
 358                 tmp = IMG_Load(s);
 359                 free(s);
 360                 if(tmp) {
 361                         img = SDL_DisplayFormat(tmp);
 362                         SDL_FreeSurface(tmp);
 363                 }
 364         }
 365         return img;
 366 }
 367
 368 void
 369 load_ship(void)
 370 {
 371         load_sprite(SPRITE(&ship), "ship.png");
 372 }
 373
 374 void font_cleanup() {
 375         font_free(g_font);
 376 }
 377
 378 int
 379 init(void) {
 380
 381         int i;
 382         char *s;
 383         Uint32 flag;
 384
 385         // Where are our data files?
 386         if(!find_files()) exit(1);
 387         read_high_score_table();
 388
 389         if(opt_sound) {
 390                 // Initialize SDL with audio and video
 391                 if(SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO) != 0) {
 392                         opt_sound = 0;
 393                         fputs("Can't open sound, starting without it\n", stderr);
 394                         atexit(SDL_Quit);
 395                 } else {
 396                         atexit(SDL_Quit);
 397                         atexit(SDL_CloseAudio);
 398                         opt_sound = init_sound();
 399                 }
 400         } else {
 401                 // Initialize with video only
 402                 CONDERROR(SDL_Init(SDL_INIT_VIDEO) != 0);
 403                 atexit(SDL_Quit);
 404         }
 405
 406         play_tune(TUNE_TITLE_PAGE);
 407
 408         // Attempt to get the required video size
 409         flag = SDL_DOUBLEBUF | SDL_HWSURFACE;
 410         if(opt_fullscreen) flag |= SDL_FULLSCREEN;
 411         surf_screen = SDL_SetVideoMode(XSIZE,YSIZE,16,flag);
 412
 413         // Set the title bar text
 414         SDL_WM_SetCaption("Variations on Rockdodger", "VoR");
 415
 416         NULLERROR(surf_screen);
 417
 418         // Set the heat color from the range 0 (cold) to 300 (blue-white)
 419         for(i = 0; i<W*3; i++) {
 420                 heatcolor[i] = SDL_MapRGB(
 421                         surf_screen->format,
 422                         (i<W)?(i*M/W):(M),(i<W)?0:(i<2*W)?((i-W)*M/W):M,(i<2*W)?0:((i-W)*M/W) // Got that?
 423                 );
 424         }
 425
 426         // Load the banners
 427         NULLERROR(surf_b_variations = load_image("b_variations.png"));
 428         NULLERROR(surf_b_on = load_image("b_on.png"));
 429         NULLERROR(surf_b_rockdodger = load_image("b_rockdodger.png"));
 430
 431         NULLERROR(surf_b_game = load_image("b_game.png"));
 432         NULLERROR(surf_b_over = load_image("b_over.png"));
 433
 434         // Load the life indicator (small ship) graphic.
 435         NULLERROR(surf_life = load_image("life.png"));
 436
 437         // Load the font image
 438         s = add_data_path("font.png");
 439         if(s) {
 440                 g_font = font_load(s);
 441                 atexit(&font_cleanup);
 442         } else {
 443                 fprintf(stderr, "could create path to font\n");
 444                 exit(1);
 445         }
 446
 447         init_engine_dots();
 448         init_dust();
 449
 450         init_sprites();
 451         add_sprite(SPRITE(&ship));
 452
 453         // Remove the mouse cursor
 454 #ifdef SDL_DISABLE
 455         SDL_ShowCursor(SDL_DISABLE);
 456 #endif
 457
 458         return 0;
 459 }
 460
 461 void
 462 show_lives(void)
 463 {
 464         int i;
 465         SDL_Rect dest;
 466
 467         for(i=0; i<ship.lives-1; i++) {
 468                 dest.x = (i + 1)*(surf_life->w + 10);
 469                 dest.y = 20;
 470                 SDL_BlitSurface(surf_life, NULL, surf_screen, &dest);
 471         }
 472 }
 473
 474 void
 475 draw_game_over(void)
 476 {
 477         int x;
 478         char *text0, *text1;
 479         SDL_Rect dest;
 480
 481         fadetimer += t_frame;
 482
 483         dest.x = (XSIZE-surf_b_game->w)/2;
 484         dest.y = (YSIZE-surf_b_game->h)/2-40;
 485         SDL_BlitSurface(surf_b_game,NULL,surf_screen,&dest);
 486
 487         dest.x = (XSIZE-surf_b_over->w)/2;
 488         dest.y = (YSIZE-surf_b_over->h)/2 + 40;
 489         SDL_BlitSurface(surf_b_over,NULL,surf_screen,&dest);
 490
 491         if(new_high_score(score)) {
 492                 text0 = "New High Score!";
 493                 text1 = "Press SPACE to continue";
 494         } else {
 495                 text0 = msgs[g_easy][0];
 496                 text1 = msgs[g_easy][1];
 497         }
 498
 499         x = (XSIZE-font_width(text0))/2 + cos(fadetimer/9)*10;
 500         font_write(x,YSIZE-100 + cos(fadetimer/6)*5,text0);
 501
 502         x = (XSIZE-font_width(text1))/2 + sin(fadetimer/9)*10;
 503         font_write(x,YSIZE-50 + sin(fadetimer/4)*5,text1);
 504 }
 505
 506 void
 507 draw_title_page(void)
 508 {
 509         int x;
 510         char *text;
 511         SDL_Rect dest;
 512
 513         fadetimer += t_frame/2.0;
 514
 515         dest.x = (XSIZE-surf_b_variations->w)/2 + cos(fadetimer/6.5)*10;
 516         dest.y = (YSIZE/2-surf_b_variations->h)/2 + sin(fadetimer/5.0)*10;
 517         SDL_BlitSurface(surf_b_variations,NULL,surf_screen,&dest);
 518
 519         dest.x = (XSIZE-surf_b_on->w)/2 + cos((fadetimer + 1.0)/6.5)*10;
 520         dest.y = (YSIZE/2-surf_b_on->h)/2 + surf_b_variations->h + 20 + sin((fadetimer + 1.0)/5.0)*10;
 521         SDL_BlitSurface(surf_b_on,NULL,surf_screen,&dest);
 522
 523         dest.x = (XSIZE-surf_b_rockdodger->w)/2 + cos((fadetimer + 2.0)/6.5)*10;
 524         dest.y = (YSIZE/2-surf_b_rockdodger->h)/2 + surf_b_variations->h + surf_b_on->h + 40 + sin((fadetimer + 2.0)/5)*10;
 525         SDL_BlitSurface(surf_b_rockdodger,NULL,surf_screen,&dest);
 526
 527         text = msgs[g_easy][(int)(fadetimer/35)%NSEQUENCE];
 528         x = (XSIZE-font_width(text))/2 + cos(fadetimer/4.5)*10;
 529         font_write(x,YSIZE-100 + cos(fadetimer/3)*5,text);
 530
 531         text = "Version " VERSION;
 532         x = (XSIZE-font_width(text))/2 + sin(fadetimer/4.5)*10;
 533         font_write(x,YSIZE-50 + sin(fadetimer/2)*5,text);
 534 }
 535
 536 void
 537 draw(void)
 538 {
 539         SDL_FillRect(surf_screen,NULL,0);  // black background
 540         draw_dots(surf_screen);            // background dots
 541         draw_sprite(SPRITE(&ship));
 542         draw_rocks();
 543
 544         show_lives();
 545         show_score();
 546
 547         switch (state) {
 548                 case GAME_OVER: draw_game_over(); break;
 549
 550                 case TITLE_PAGE: draw_title_page(); break;
 551
 552                 case HIGH_SCORE_ENTRY: play_tune(TUNE_HIGH_SCORE_ENTRY);
 553                         // and fall through to
 554                 case HIGH_SCORE_DISPLAY:
 555                         // Display de list o high scores mon.
 556                         display_scores(surf_screen, 150,50);
 557                         break;
 558                 case GAMEPLAY:
 559                 case DEAD_PAUSE:
 560                         ; // no action necessary
 561         }
 562
 563         // Update the surface
 564         SDL_Flip(surf_screen);
 565 }
 566
 567 static inline void
 568 kill_ship(struct ship *ship)
 569 {
 570         play_sound(SOUND_BANG);
 571         new_bang_dots(SPRITE(ship));
 572         if(--ship->lives) {
 573                 state = DEAD_PAUSE;
 574                 state_timeout = DEAD_PAUSE_LENGTH;
 575                 // want ship to be invisible, but keep drifting at sqrt(speed)
 576                 // to leave it in the middle of the space from the explosion.
 577                 ship->flags = MOVE;
 578                 ship->dx = (ship->dx < 0) ? -sqrt(-ship->dx) : sqrt(ship->dx);
 579                 ship->dy = (ship->dy < 0) ? -sqrt(-ship->dy) : sqrt(ship->dy);
 580                 if(ship->dx < BARRIER_SPEED) ship->dx = BARRIER_SPEED;
 581         } else {
 582                 state = GAME_OVER;
 583                 state_timeout = 200.0;
 584                 fadetimer = 0.0;
 585                 ship->flags = 0;
 586                 // scrolling is based on the ship speed, so we need to reset it.
 587                 ship->dx = BARRIER_SPEED; ship->dy = 0;
 588         }
 589 }
 590
 591 void
 592 do_collision(Sprite *a, Sprite *b)
 593 {
 594         if(a->type == SHIP) kill_ship((struct ship *)a);
 595         else if(b->type == SHIP) kill_ship((struct ship *)b);
 596         else bounce(a, b);
 597 }
 598
 599 void
 600 init_score_entry(void)
 601 {
 602         SDL_Event e;
 603         state = HIGH_SCORE_ENTRY;
 604         state_timeout = 5.0e6;
 605         SDL_EnableUNICODE(1);
 606         while(SDL_PollEvent(&e))
 607                 ;
 608         insert_score(score);
 609 }
 610
 611 // Count down the state timer, and change state when it gets to zero or less;
 612 void
 613 update_state(float ticks)
 614 {
 615         state_timeout -= ticks*3;
 616         if(state_timeout > 0) return;
 617
 618         switch(state) {
 619                 case GAMEPLAY: break;  // no action necessary
 620                 case DEAD_PAUSE:
 621                         // Restore the ship and continue playing
 622                         ship.flags = DRAW|MOVE|COLLIDE;
 623                         state = GAMEPLAY;
 624                         play_tune(TUNE_GAMEPLAY);
 625                         break;
 626                 case GAME_OVER:
 627                         if(new_high_score(score)) init_score_entry();
 628                         else {
 629                                 state = HIGH_SCORE_DISPLAY;
 630                                 state_timeout = 400;
 631                         }
 632                         break;
 633                 case HIGH_SCORE_DISPLAY:
 634                         state = TITLE_PAGE;
 635                         state_timeout = 600.0;
 636                         fadetimer = 0.0;
 637                         break;
 638                 case HIGH_SCORE_ENTRY:
 639                         break;
 640                 case TITLE_PAGE:
 641                         state = HIGH_SCORE_DISPLAY;
 642                         state_timeout = 200.0;
 643                         break;
 644         }
 645 }
 646
 647 void
 648 gameloop() {
 649         SDL_Event e;
 650         Uint8 *keystate;
 651         float tmp;
 652
 653         for(;;) {
 654                 ms_frame = SDL_GetTicks() - ms_end;
 655                 ms_end += ms_frame;
 656                 if(ms_frame > 1000) {
 657                         ms_frame = 1000;
 658                 }
 659                 t_frame = gamespeed * ms_frame / 50;
 660                 frames++;
 661
 662                 while(SDL_PollEvent(&e)) {
 663                         switch(e.type) {
 664                                 case SDL_QUIT: return;
 665                                 case SDL_KEYDOWN:
 666                                         if(state == HIGH_SCORE_ENTRY) {
 667                                                 if(!process_score_input(&e.key.keysym)) {
 668                                                         // Write the high score table to the file
 669                                                         write_high_score_table();
 670                                                         // continue to display the scores briefly
 671                                                         state = HIGH_SCORE_DISPLAY;
 672                                                         state_timeout = 200;
 673                                                         play_tune(TUNE_TITLE_PAGE);
 674                                                 }
 675                                         } else if(e.key.keysym.sym == SDLK_q) {
 676                                                 return;
 677                                         }
 678
 679                                         if(e.key.keysym.sym == SDLK_ESCAPE) {
 680                                                 return;
 681                                         }
 682                                         break;
 683                         }
 684                 }
 685                 keystate = SDL_GetKeyState(NULL);
 686
 687                 if(state == GAMEPLAY) {
 688                         if(!paused) {
 689                                 score += ms_frame;
 690
 691                                 if(keystate[SDLK_LEFT]  || keystate[SDLK_h]) { ship.dx -= THRUSTER_STRENGTH*t_frame; ship.jets |= 1<<0;}
 692                                 if(keystate[SDLK_DOWN]  || keystate[SDLK_t]) { ship.dy += THRUSTER_STRENGTH*t_frame; ship.jets |= 1<<1;}
 693                                 if(keystate[SDLK_RIGHT] || keystate[SDLK_n]) { ship.dx += THRUSTER_STRENGTH*t_frame; ship.jets |= 1<<2;}
 694                                 if(keystate[SDLK_UP]    || keystate[SDLK_c]) { ship.dy -= THRUSTER_STRENGTH*t_frame; ship.jets |= 1<<3;}
 695                                 if(keystate[SDLK_3])            { SDL_SaveBMP(surf_screen, "snapshot.bmp"); }
 696                         }
 697
 698                         if(keystate[SDLK_p] | keystate[SDLK_s]) {
 699                                 if(!pausedown) {
 700                                         paused = !paused;
 701                                         pausedown = 1;
 702                                         if(!paused) ms_end = SDL_GetTicks();
 703                                 }
 704                         } else {
 705                                 pausedown = 0;
 706                         }
 707                 }
 708
 709                 if(!paused) {
 710                         update_state(t_frame);
 711
 712                         // SCROLLING
 713                         tmp = (ship.y+ship.h/2 + ship.dy*t_frame - YSCROLLTO)/25 + (ship.dy-screendy);
 714                         screendy += tmp * t_frame/12;
 715                         tmp = (ship.x+ship.w/2 + ship.dx*t_frame - XSCROLLTO)/25 + (ship.dx-screendx);
 716                         screendx += tmp * t_frame/12;
 717                         // taper off so we don't hit the barrier abruptly.
 718                         // (if we would hit in < 2 seconds, adjust to 2 seconds).
 719                         if(dist_ahead + (screendx - BARRIER_SPEED)*TO_TICKS(2) < 0)
 720                                 screendx = BARRIER_SPEED - (dist_ahead/TO_TICKS(2));
 721                         dist_ahead += (screendx - BARRIER_SPEED)*t_frame;
 722                         if(MAX_DIST_AHEAD >= 0) dist_ahead = min(dist_ahead, MAX_DIST_AHEAD);
 723
 724                         move_sprites(t_frame);  new_rocks(t_frame);
 725                         move_engine_dots(t_frame); new_engine_dots(t_frame);
 726                         move_bang_dots(t_frame);
 727                         move_dust(t_frame);
 728
 729                         collisions();
 730
 731                         // BOUNCE off left or right edge of screen
 732                         if(ship.x < 0 || ship.x+ship.w > XSIZE) {
 733                                 ship.x -= (ship.dx-screendx)*t_frame;
 734                                 ship.dx = screendx - (ship.dx-screendx)*BOUNCINESS;
 735                         }
 736
 737                         // BOUNCE off top or bottom of screen
 738                         if(ship.y < 0 || ship.y+ship.h > YSIZE) {
 739                                 ship.y -= (ship.dy-screendy)*t_frame;
 740                                 ship.dy = screendy - (ship.dy-screendy)*BOUNCINESS;
 741                         }
 742
 743                         draw();
 744
 745                         // new game
 746                         if((keystate[SDLK_SPACE] || keystate[SDLK_1] || keystate[SDLK_2])
 747                            && (state == HIGH_SCORE_DISPLAY
 748                                || state == TITLE_PAGE
 749                                || state == GAME_OVER)) {
 750                                 if(state == GAME_OVER && new_high_score(score))
 751                                         init_score_entry();
 752                                 else {
 753                                         if((keystate[SDLK_SPACE] && !initial_rocks) || keystate[SDLK_2]) {
 754                                                 g_easy = 0;
 755                                                 initial_rocks = NORMAL_I_ROCKS;
 756                                                 final_rocks = NORMAL_F_ROCKS;
 757                                                 if(gamespeed == EASY_GAMESPEED)
 758                                                         gamespeed = NORMAL_GAMESPEED;
 759                                         } else if(keystate[SDLK_1]) {
 760                                                 g_easy = 1;
 761                                                 initial_rocks = EASY_I_ROCKS;
 762                                                 final_rocks = EASY_F_ROCKS;
 763                                                 gamespeed = EASY_GAMESPEED;
 764                                         }
 765                                         reset_sprites();
 766                                         reset_rocks();
 767                                         screendx = BARRIER_SPEED; screendy = 0;
 768
 769                                         ship.x = XSIZE/2.2; ship.y = YSIZE/2 - ship.w/2;
 770                                         ship.dx = screendx; ship.dy = screendy;
 771                                         ship.lives = 4;
 772                                         ship.flags = MOVE|DRAW|COLLIDE;
 773                                         add_sprite(SPRITE(&ship));
 774
 775                                         score = 0;
 776
 777                                         state = GAMEPLAY;
 778                                         play_tune(TUNE_GAMEPLAY);
 779                                 }
 780                         }
 781
 782                         ship.jets = 0;
 783                 }
 784
 785                 if(state == TITLE_PAGE && keystate[SDLK_h]) {
 786                         state = HIGH_SCORE_DISPLAY;
 787                         state_timeout = 400;
 788                 }
 789         }
 790 }
 791
 792 int
 793 main(int argc, char **argv) {
 794         if(!parse_opts(argc, argv)) return 1;
 795
 796         if(init()) {
 797                 printf ("vor: SDL error: '%s'\n",initerror);
 798                 return 1;
 799         }
 800
 801         start = SDL_GetTicks();
 802         frames = 0;
 803         gameloop();
 804         end = SDL_GetTicks();
 805         // printf("%ld frames in %ld ms, %.2f fps.\n", frames, end-start, frames * 1000.0 / (end-start));
 806
 807         return 0;
 808 }