app.c 24 KB

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  1. /* Copyright (C) 2023 Salvatore Sanfilippo -- All Rights Reserved
  2. * See the LICENSE file for information about the license. */
  3. #include <furi.h>
  4. #include <furi_hal.h>
  5. #include <input/input.h>
  6. #include <gui/gui.h>
  7. #include <stdlib.h>
  8. #include <gui/gui.h>
  9. #include <gui/view_dispatcher.h>
  10. #include <gui/scene_manager.h>
  11. #include <math.h>
  12. #include <notification/notification.h>
  13. #include <notification/notification_messages.h>
  14. #define TAG "Asteroids" // Used for logging
  15. #define DEBUG_MSG 1
  16. #define SCREEN_XRES 128
  17. #define SCREEN_YRES 64
  18. #define GAME_START_LIVES 3
  19. #define TTLBUL 30 /* Bullet time to live, in ticks. */
  20. #define MAXBUL 5 /* Max bullets on the screen. */
  21. #define MAXAST 32 /* Max asteroids on the screen. */
  22. #define SHIP_HIT_ANIMATION_LEN 15
  23. #ifndef PI
  24. #define PI 3.14159265358979f
  25. #endif
  26. /* ============================ Data structures ============================= */
  27. typedef struct Ship {
  28. float x, /* Ship x position. */
  29. y, /* Ship y position. */
  30. vx, /* x velocity. */
  31. vy, /* y velocity. */
  32. rot; /* Current rotation. 2*PI full ortation. */
  33. } Ship;
  34. typedef struct Bullet {
  35. float x, y, vx, vy; /* Fields like in ship. */
  36. uint32_t ttl; /* Time to live, in ticks. */
  37. } Bullet;
  38. typedef struct Asteroid {
  39. float x, y, vx, vy, rot, /* Fields like ship. */
  40. rot_speed, /* Angular velocity (rot speed and sense). */
  41. size; /* Asteroid size. */
  42. uint8_t shape_seed; /* Seed to give random shape. */
  43. } Asteroid;
  44. typedef struct AsteroidsApp {
  45. /* GUI */
  46. Gui* gui;
  47. ViewPort* view_port; /* We just use a raw viewport and we render
  48. everything into the low level canvas. */
  49. FuriMessageQueue* event_queue; /* Keypress events go here. */
  50. /* Game state. */
  51. int running; /* Once false exists the app. */
  52. bool gameover; /* Gameover status. */
  53. uint32_t ticks; /* Game ticks. Increments at each refresh. */
  54. uint32_t score; /* Game score. */
  55. uint32_t lives; /* Number of lives in the current game. */
  56. uint32_t ship_hit; /* When non zero, the ship was hit by an asteroid
  57. and we need to show an animation as long as
  58. its value is non-zero (and decrease it's value
  59. at each tick of animation). */
  60. /* Ship state. */
  61. struct Ship ship;
  62. /* Bullets state. */
  63. struct Bullet bullets[MAXBUL]; /* Each bullet state. */
  64. int bullets_num; /* Active bullets. */
  65. uint32_t last_bullet_tick; /* Tick the last bullet was fired. */
  66. /* Asteroids state. */
  67. Asteroid asteroids[MAXAST]; /* Each asteroid state. */
  68. int asteroids_num; /* Active asteroids. */
  69. uint32_t pressed[InputKeyMAX]; /* pressed[id] is true if pressed.
  70. Each array item contains the time
  71. in milliseconds the key was pressed. */
  72. bool fire; /* Short press detected: fire a bullet. */
  73. } AsteroidsApp;
  74. const NotificationSequence sequence_crash = {
  75. &message_red_255,
  76. &message_vibro_on,
  77. // &message_note_g5, // Play sound but currently disabled
  78. &message_delay_25,
  79. // &message_note_e5,
  80. &message_vibro_off,
  81. &message_sound_off,
  82. NULL,
  83. };
  84. const NotificationSequence sequence_bullet_fired = {
  85. &message_vibro_on,
  86. // &message_note_g5, // Play sound but currently disabled. Need On/Off menu setting
  87. &message_delay_10,
  88. &message_delay_1,
  89. &message_delay_1,
  90. &message_delay_1,
  91. &message_delay_1,
  92. &message_delay_1,
  93. // &message_note_e5,
  94. &message_vibro_off,
  95. &message_sound_off,
  96. NULL,
  97. };
  98. /* ============================== Prototyeps ================================ */
  99. // Only functions called before their definition are here.
  100. void restart_game_after_gameover(AsteroidsApp* app);
  101. uint32_t key_pressed_time(AsteroidsApp* app, InputKey key);
  102. /* ============================ 2D drawing ================================== */
  103. /* This structure represents a polygon of at most POLY_MAX points.
  104. * The function draw_poly() is able to render it on the screen, rotated
  105. * by the amount specified. */
  106. #define POLY_MAX 8
  107. typedef struct Poly {
  108. float x[POLY_MAX];
  109. float y[POLY_MAX];
  110. uint32_t points; /* Number of points actually populated. */
  111. } Poly;
  112. /* Define the polygons we use. */
  113. Poly ShipPoly = {{-3, 0, 3}, {-3, 6, -3}, 3};
  114. /* Rotate the point of the poligon 'poly' and store the new rotated
  115. * polygon in 'rot'. The polygon is rotated by an angle 'a', with
  116. * center at 0,0. */
  117. void rotate_poly(Poly* rot, Poly* poly, float a) {
  118. /* We want to compute sin(a) and cos(a) only one time
  119. * for every point to rotate. It's a slow operation. */
  120. float sin_a = (float)sin(a);
  121. float cos_a = (float)cos(a);
  122. for(uint32_t j = 0; j < poly->points; j++) {
  123. rot->x[j] = poly->x[j] * cos_a - poly->y[j] * sin_a;
  124. rot->y[j] = poly->y[j] * cos_a + poly->x[j] * sin_a;
  125. }
  126. rot->points = poly->points;
  127. }
  128. /* This is an 8 bit LFSR we use to generate a predictable and fast
  129. * pseudorandom sequence of numbers, to give a different shape to
  130. * each asteroid. */
  131. void lfsr_next(unsigned char* prev) {
  132. unsigned char lsb = *prev & 1;
  133. *prev = *prev >> 1;
  134. if(lsb == 1) *prev ^= 0b11000111;
  135. *prev ^= *prev << 7; /* Mix things a bit more. */
  136. }
  137. /* Render the polygon 'poly' at x,y, rotated by the specified angle. */
  138. void draw_poly(Canvas* const canvas, Poly* poly, uint8_t x, uint8_t y, float a) {
  139. Poly rot;
  140. rotate_poly(&rot, poly, a);
  141. canvas_set_color(canvas, ColorBlack);
  142. for(uint32_t j = 0; j < rot.points; j++) {
  143. uint32_t a = j;
  144. uint32_t b = j + 1;
  145. if(b == rot.points) b = 0;
  146. canvas_draw_line(canvas, x + rot.x[a], y + rot.y[a], x + rot.x[b], y + rot.y[b]);
  147. }
  148. }
  149. /* A bullet is just a + pixels pattern. A single pixel is not
  150. * visible enough. */
  151. void draw_bullet(Canvas* const canvas, Bullet* b) {
  152. canvas_draw_dot(canvas, b->x - 1, b->y);
  153. canvas_draw_dot(canvas, b->x + 1, b->y);
  154. canvas_draw_dot(canvas, b->x, b->y);
  155. canvas_draw_dot(canvas, b->x, b->y - 1);
  156. canvas_draw_dot(canvas, b->x, b->y + 1);
  157. }
  158. /* Draw an asteroid. The asteroid shapes is computed on the fly and
  159. * is not stored in a permanent shape structure. In order to generate
  160. * the shape, we use an initial fixed shape that we resize according
  161. * to the asteroid size, perturbate according to the asteroid shape
  162. * seed, and finally draw it rotated of the right amount. */
  163. void draw_asteroid(Canvas* const canvas, Asteroid* ast) {
  164. Poly ap;
  165. /* Start with what is kinda of a circle. Note that this could be
  166. * stored into a template and copied here, to avoid computing
  167. * sin() / cos(). But the Flipper can handle it without problems. */
  168. uint8_t r = ast->shape_seed;
  169. for(int j = 0; j < 8; j++) {
  170. float a = (PI * 2) / 8 * j;
  171. /* Before generating the point, to make the shape unique generate
  172. * a random factor between .7 and 1.3 to scale the distance from
  173. * the center. However this asteroid should have its unique shape
  174. * that remains always the same, so we use a predictable PRNG
  175. * implemented by an 8 bit shift register. */
  176. lfsr_next(&r);
  177. float scaling = .7 + ((float)r / 255 * .6);
  178. ap.x[j] = (float)sin(a) * ast->size * scaling;
  179. ap.y[j] = (float)cos(a) * ast->size * scaling;
  180. }
  181. ap.points = 8;
  182. draw_poly(canvas, &ap, ast->x, ast->y, ast->rot);
  183. }
  184. /* Draw small ships in the top-right part of the screen, one for
  185. * each left live. */
  186. void draw_left_lives(Canvas* const canvas, AsteroidsApp* app) {
  187. int lives = app->lives;
  188. int x = SCREEN_XRES - 5;
  189. Poly mini_ship = {{-2, 0, 2}, {-2, 4, -2}, 3};
  190. while(lives--) {
  191. draw_poly(canvas, &mini_ship, x, 6, PI);
  192. x -= 6;
  193. }
  194. }
  195. /* Given the current position, update it according to the velocity and
  196. * wrap it back to the other side if the object went over the screen. */
  197. void update_pos_by_velocity(float* x, float* y, float vx, float vy) {
  198. /* Return back from one side to the other of the screen. */
  199. *x += vx;
  200. *y += vy;
  201. if(*x >= SCREEN_XRES)
  202. *x = 0;
  203. else if(*x < 0)
  204. *x = SCREEN_XRES - 1;
  205. if(*y >= SCREEN_YRES)
  206. *y = 0;
  207. else if(*y < 0)
  208. *y = SCREEN_YRES - 1;
  209. }
  210. /* Render the current game screen. */
  211. void render_callback(Canvas* const canvas, void* ctx) {
  212. AsteroidsApp* app = ctx;
  213. /* Clear screen. */
  214. canvas_set_color(canvas, ColorWhite);
  215. canvas_draw_box(canvas, 0, 0, SCREEN_XRES - 1, SCREEN_YRES - 1);
  216. /* Draw score. */
  217. canvas_set_color(canvas, ColorBlack);
  218. canvas_set_font(canvas, FontSecondary);
  219. char score[32];
  220. snprintf(score, sizeof(score), "%lu", app->score);
  221. canvas_draw_str(canvas, 0, 8, score);
  222. /* Draw left ships. */
  223. draw_left_lives(canvas, app);
  224. /* Draw ship, asteroids, bullets. */
  225. draw_poly(canvas, &ShipPoly, app->ship.x, app->ship.y, app->ship.rot);
  226. for(int j = 0; j < app->bullets_num; j++) draw_bullet(canvas, &app->bullets[j]);
  227. for(int j = 0; j < app->asteroids_num; j++) draw_asteroid(canvas, &app->asteroids[j]);
  228. /* Game over text. */
  229. if(app->gameover) {
  230. canvas_set_color(canvas, ColorBlack);
  231. canvas_set_font(canvas, FontPrimary);
  232. canvas_draw_str(canvas, 28, 35, "GAME OVER");
  233. canvas_set_font(canvas, FontSecondary);
  234. canvas_draw_str(canvas, 25, 50, "Press OK to restart");
  235. }
  236. }
  237. /* ============================ Game logic ================================== */
  238. float distance(float x1, float y1, float x2, float y2) {
  239. float dx = x1 - x2;
  240. float dy = y1 - y2;
  241. return sqrt(dx * dx + dy * dy);
  242. }
  243. /* Detect a collision between the object at x1,y1 of radius r1 and
  244. * the object at x2, y2 of radius r2. A factor < 1 will make the
  245. * function detect the collision even if the objects are yet not
  246. * relly touching, while a factor > 1 will make it detect the collision
  247. * only after they are a bit overlapping. It basically is used to
  248. * rescale the distance.
  249. *
  250. * Note that in this simplified 2D world, objects are all considered
  251. * spheres (this is why this function only takes the radius). This
  252. * is, after all, kinda accurate for asteroids, for bullets, and
  253. * even for the ship "core" itself. */
  254. bool objects_are_colliding(float x1, float y1, float r1, float x2, float y2, float r2, float factor) {
  255. /* The objects are colliding if the distance between object 1 and 2
  256. * is smaller than the sum of the two radiuses r1 and r2.
  257. * So it would be like: sqrt((x1-x2)^2+(y1-y2)^2) < r1+r2.
  258. * However we can avoid computing the sqrt (which is slow) by
  259. * squaring the second term and removing the square root, making
  260. * the comparison like this:
  261. *
  262. * (x1-x2)^2+(y1-y2)^2 < (r1+r2)^2. */
  263. float dx = (x1 - x2) * factor;
  264. float dy = (y1 - y2) * factor;
  265. float rsum = r1 + r2;
  266. return dx * dx + dy * dy < rsum * rsum;
  267. }
  268. /* Create a new bullet headed in the same direction of the ship. */
  269. void ship_fire_bullet(AsteroidsApp* app) {
  270. if(app->bullets_num == MAXBUL) return;
  271. notification_message(furi_record_open(RECORD_NOTIFICATION), &sequence_bullet_fired);
  272. Bullet* b = &app->bullets[app->bullets_num];
  273. b->x = app->ship.x;
  274. b->y = app->ship.y;
  275. b->vx = -sin(app->ship.rot);
  276. b->vy = cos(app->ship.rot);
  277. /* Ship should fire from its head, not in the middle. */
  278. b->x += b->vx * 5;
  279. b->y += b->vy * 5;
  280. /* Give the bullet some velocity (for now the vector is just
  281. * normalized to 1). */
  282. b->vx *= 3;
  283. b->vy *= 3;
  284. /* It's more realistic if we add the velocity vector of the
  285. * ship, too. Otherwise if the ship is going fast the bullets
  286. * will be slower, which is not how the world works. */
  287. b->vx += app->ship.vx;
  288. b->vy += app->ship.vy;
  289. b->ttl = TTLBUL; /* The bullet will disappear after N ticks. */
  290. app->bullets_num++;
  291. }
  292. /* Remove the specified bullet by id (index in the array). */
  293. void remove_bullet(AsteroidsApp* app, int bid) {
  294. /* Replace the top bullet with the empty space left
  295. * by the removal of this bullet. This way we always take the
  296. * array dense, which is an advantage when looping. */
  297. int n = --app->bullets_num;
  298. if(n && bid != n) app->bullets[bid] = app->bullets[n];
  299. }
  300. /* Create a new asteroid, away from the ship. Return the
  301. * pointer to the asteroid object, so that the caller can change
  302. * certain things of the asteroid if needed. */
  303. Asteroid* add_asteroid(AsteroidsApp* app) {
  304. if(app->asteroids_num == MAXAST) return NULL;
  305. float size = 4 + rand() % 15;
  306. float min_distance = 20;
  307. float x, y;
  308. do {
  309. x = rand() % SCREEN_XRES;
  310. y = rand() % SCREEN_YRES;
  311. } while(distance(app->ship.x, app->ship.y, x, y) < min_distance + size);
  312. Asteroid* a = &app->asteroids[app->asteroids_num++];
  313. a->x = x;
  314. a->y = y;
  315. a->vx = 2 * (-.5 + ((float)rand() / RAND_MAX));
  316. a->vy = 2 * (-.5 + ((float)rand() / RAND_MAX));
  317. a->size = size;
  318. a->rot = 0;
  319. a->rot_speed = ((float)rand() / RAND_MAX) / 10;
  320. if(app->ticks & 1) a->rot_speed = -(a->rot_speed);
  321. a->shape_seed = rand() & 255;
  322. return a;
  323. }
  324. /* Remove the specified asteroid by id (index in the array). */
  325. void remove_asteroid(AsteroidsApp* app, int id) {
  326. /* Replace the top asteroid with the empty space left
  327. * by the removal of this one. This way we always take the
  328. * array dense, which is an advantage when looping. */
  329. int n = --app->asteroids_num;
  330. if(n && id != n) app->asteroids[id] = app->asteroids[n];
  331. }
  332. /* Called when an asteroid was reached by a bullet. The asteroid
  333. * hit is the one with the specified 'id'. */
  334. void asteroid_was_hit(AsteroidsApp* app, int id) {
  335. float sizelimit = 6; // Smaller than that polverize in one shot.
  336. Asteroid* a = &app->asteroids[id];
  337. /* Asteroid is large enough to break into fragments. */
  338. float size = a->size;
  339. float x = a->x, y = a->y;
  340. remove_asteroid(app, id);
  341. if(size > sizelimit) {
  342. int max_fragments = size / sizelimit;
  343. int fragments = 2 + rand() % max_fragments;
  344. float newsize = size / fragments;
  345. if(newsize < 2) newsize = 2;
  346. for(int j = 0; j < fragments; j++) {
  347. a = add_asteroid(app);
  348. if(a == NULL) break; // Too many asteroids on screen.
  349. a->x = x + -(size / 2) + rand() % (int)newsize;
  350. a->y = y + -(size / 2) + rand() % (int)newsize;
  351. a->size = newsize;
  352. }
  353. } else {
  354. app->score++;
  355. }
  356. }
  357. /* Set gameover state. When in game-over mode, the game displays a gameover
  358. * text with a background of many asteroids floating around. */
  359. void game_over(AsteroidsApp* app) {
  360. restart_game_after_gameover(app);
  361. app->gameover = true;
  362. int asteroids = 8;
  363. while(asteroids-- && add_asteroid(app) != NULL)
  364. ;
  365. }
  366. /* Function called when a collision between the asteroid and the
  367. * ship is detected. */
  368. void ship_was_hit(AsteroidsApp* app) {
  369. app->ship_hit = SHIP_HIT_ANIMATION_LEN;
  370. if(app->lives) {
  371. app->lives--;
  372. } else {
  373. game_over(app);
  374. }
  375. }
  376. /* Restart game after the ship is hit. Will reset the ship position, bullets
  377. * and asteroids to restart the game. */
  378. void restart_game(AsteroidsApp* app) {
  379. app->ship.x = SCREEN_XRES / 2;
  380. app->ship.y = SCREEN_YRES / 2;
  381. app->ship.rot = PI; /* Start headed towards top. */
  382. app->ship.vx = 0;
  383. app->ship.vy = 0;
  384. app->bullets_num = 0;
  385. app->last_bullet_tick = 0;
  386. app->asteroids_num = 0;
  387. }
  388. /* Called after gameover to restart the game. This function
  389. * also calls restart_game(). */
  390. void restart_game_after_gameover(AsteroidsApp* app) {
  391. app->gameover = false;
  392. app->ticks = 0;
  393. app->score = 0;
  394. app->ship_hit = 0;
  395. app->lives = GAME_START_LIVES - 1;
  396. restart_game(app);
  397. }
  398. /* Move bullets. */
  399. void update_bullets_position(AsteroidsApp* app) {
  400. for(int j = 0; j < app->bullets_num; j++) {
  401. update_pos_by_velocity(
  402. &app->bullets[j].x, &app->bullets[j].y, app->bullets[j].vx, app->bullets[j].vy);
  403. if(--app->bullets[j].ttl == 0) {
  404. remove_bullet(app, j);
  405. j--; /* Process this bullet index again: the removal will
  406. fill it with the top bullet to take the array dense. */
  407. }
  408. }
  409. }
  410. /* Move asteroids. */
  411. void update_asteroids_position(AsteroidsApp* app) {
  412. for(int j = 0; j < app->asteroids_num; j++) {
  413. update_pos_by_velocity(
  414. &app->asteroids[j].x, &app->asteroids[j].y, app->asteroids[j].vx, app->asteroids[j].vy);
  415. app->asteroids[j].rot += app->asteroids[j].rot_speed;
  416. if(app->asteroids[j].rot < 0)
  417. app->asteroids[j].rot = 2 * PI;
  418. else if(app->asteroids[j].rot > 2 * PI)
  419. app->asteroids[j].rot = 0;
  420. }
  421. }
  422. /* Collision detection and game state update based on collisions. */
  423. void detect_collisions(AsteroidsApp* app) {
  424. /* Detect collision between bullet and asteroid. */
  425. for(int j = 0; j < app->bullets_num; j++) {
  426. Bullet* b = &app->bullets[j];
  427. for(int i = 0; i < app->asteroids_num; i++) {
  428. Asteroid* a = &app->asteroids[i];
  429. if(objects_are_colliding(a->x, a->y, a->size, b->x, b->y, 1.5, 1)) {
  430. asteroid_was_hit(app, i);
  431. remove_bullet(app, j);
  432. /* The bullet no longer exist. Break the loop.
  433. * However we want to start processing from the
  434. * same bullet index, since now it is used by
  435. * another bullet (see remove_bullet()). */
  436. j--; /* Scan this j value again. */
  437. break;
  438. }
  439. }
  440. }
  441. /* Detect collision between ship and asteroid. */
  442. for(int j = 0; j < app->asteroids_num; j++) {
  443. Asteroid* a = &app->asteroids[j];
  444. if(objects_are_colliding(a->x, a->y, a->size, app->ship.x, app->ship.y, 4, 1)) {
  445. ship_was_hit(app);
  446. break;
  447. }
  448. }
  449. }
  450. /* This is the main game execution function, called 10 times for
  451. * second (with the Flipper screen latency, an higher FPS does not
  452. * make sense). In this function we update the position of objects based
  453. * on velocity. Detect collisions. Update the score and so forth.
  454. *
  455. * Each time this function is called, app->tick is incremented. */
  456. void game_tick(void* ctx) {
  457. AsteroidsApp* app = ctx;
  458. /* There are two special screens:
  459. *
  460. * 1. Ship was hit, we frozen the game as long as ship_hit isn't zero
  461. * again, and show an animation of a rotating ship. */
  462. if(app->ship_hit) {
  463. notification_message(furi_record_open(RECORD_NOTIFICATION), &sequence_crash);
  464. app->ship.rot += 0.5;
  465. app->ship_hit--;
  466. view_port_update(app->view_port);
  467. if(app->ship_hit == 0) {
  468. restart_game(app);
  469. }
  470. return;
  471. } else if(app->gameover) {
  472. /* 2. Game over. We need to update only background asteroids. In this
  473. * state the game just displays a GAME OVER text with the floating
  474. * asteroids in backgroud. */
  475. app->lives = GAME_START_LIVES; // Show 3 lives in game over screen to match new game start
  476. if(key_pressed_time(app, InputKeyOk) > 100) {
  477. restart_game_after_gameover(app);
  478. }
  479. update_asteroids_position(app);
  480. view_port_update(app->view_port);
  481. return;
  482. }
  483. /* Handle keypresses. */
  484. if(app->pressed[InputKeyLeft]) app->ship.rot -= .35;
  485. if(app->pressed[InputKeyRight]) app->ship.rot += .35;
  486. if(app->pressed[InputKeyUp]) {
  487. app->ship.vx -= 0.5 * (float)sin(app->ship.rot);
  488. app->ship.vy += 0.5 * (float)cos(app->ship.rot);
  489. } else if(app->pressed[InputKeyDown]) {
  490. app->ship.vx *= 0.75;
  491. app->ship.vy *= 0.75;
  492. }
  493. /* Fire a bullet if needed. app->fire is set in
  494. * asteroids_update_keypress_state() since depends on exact
  495. * pressure timing. */
  496. if(app->fire) {
  497. uint32_t bullet_min_period = 200; // In milliseconds
  498. uint32_t now = furi_get_tick();
  499. if(now - app->last_bullet_tick >= bullet_min_period) {
  500. ship_fire_bullet(app);
  501. app->last_bullet_tick = now;
  502. }
  503. app->fire = false;
  504. }
  505. /* Update positions and detect collisions. */
  506. update_pos_by_velocity(&app->ship.x, &app->ship.y, app->ship.vx, app->ship.vy);
  507. update_bullets_position(app);
  508. update_asteroids_position(app);
  509. detect_collisions(app);
  510. /* From time to time, create a new asteroid. The more asteroids
  511. * already on the screen, the smaller probability of creating
  512. * a new one. */
  513. if(app->asteroids_num == 0 || (random() % 5000) < (30 / (1 + app->asteroids_num))) {
  514. add_asteroid(app);
  515. }
  516. app->ticks++;
  517. view_port_update(app->view_port);
  518. }
  519. /* ======================== Flipper specific code =========================== */
  520. /* Here all we do is putting the events into the queue that will be handled
  521. * in the while() loop of the app entry point function. */
  522. void input_callback(InputEvent* input_event, void* ctx) {
  523. AsteroidsApp* app = ctx;
  524. furi_message_queue_put(app->event_queue, input_event, FuriWaitForever);
  525. }
  526. /* Allocate the application state and initialize a number of stuff.
  527. * This is called in the entry point to create the application state. */
  528. AsteroidsApp* asteroids_app_alloc() {
  529. AsteroidsApp* app = malloc(sizeof(AsteroidsApp));
  530. app->gui = furi_record_open(RECORD_GUI);
  531. app->view_port = view_port_alloc();
  532. view_port_draw_callback_set(app->view_port, render_callback, app);
  533. view_port_input_callback_set(app->view_port, input_callback, app);
  534. gui_add_view_port(app->gui, app->view_port, GuiLayerFullscreen);
  535. app->event_queue = furi_message_queue_alloc(8, sizeof(InputEvent));
  536. app->running = 1; /* Turns 0 when back is pressed. */
  537. restart_game_after_gameover(app);
  538. memset(app->pressed, 0, sizeof(app->pressed));
  539. return app;
  540. }
  541. /* Free what the application allocated. It is not clear to me if the
  542. * Flipper OS, once the application exits, will be able to reclaim space
  543. * even if we forget to free something here. */
  544. void asteroids_app_free(AsteroidsApp* app) {
  545. furi_assert(app);
  546. // View related.
  547. view_port_enabled_set(app->view_port, false);
  548. gui_remove_view_port(app->gui, app->view_port);
  549. view_port_free(app->view_port);
  550. furi_record_close(RECORD_GUI);
  551. furi_message_queue_free(app->event_queue);
  552. app->gui = NULL;
  553. free(app);
  554. }
  555. /* Return the time in milliseconds the specified key is continuously
  556. * pressed. Or 0 if it is not pressed. */
  557. uint32_t key_pressed_time(AsteroidsApp* app, InputKey key) {
  558. return app->pressed[key] == 0 ? 0 : furi_get_tick() - app->pressed[key];
  559. }
  560. /* Handle keys interaction. */
  561. void asteroids_update_keypress_state(AsteroidsApp* app, InputEvent input) {
  562. // Allow Rapid fire
  563. if(input.key == InputKeyOk) {
  564. app->fire = true;
  565. }
  566. if(input.type == InputTypePress) {
  567. app->pressed[input.key] = furi_get_tick();
  568. } else if(input.type == InputTypeRelease) {
  569. app->pressed[input.key] = 0;
  570. }
  571. }
  572. int32_t asteroids_app_entry(void* p) {
  573. UNUSED(p);
  574. AsteroidsApp* app = asteroids_app_alloc();
  575. /* Create a timer. We do data analysis in the callback. */
  576. FuriTimer* timer = furi_timer_alloc(game_tick, FuriTimerTypePeriodic, app);
  577. furi_timer_start(timer, furi_kernel_get_tick_frequency() / 10);
  578. /* This is the main event loop: here we get the events that are pushed
  579. * in the queue by input_callback(), and process them one after the
  580. * other. */
  581. InputEvent input;
  582. while(app->running) {
  583. FuriStatus qstat = furi_message_queue_get(app->event_queue, &input, 100);
  584. if(qstat == FuriStatusOk) {
  585. if(DEBUG_MSG)
  586. FURI_LOG_E(TAG, "Main Loop - Input: type %d key %u", input.type, input.key);
  587. /* Handle navigation here. Then handle view-specific inputs
  588. * in the view specific handling function. */
  589. if(input.type == InputTypeShort && input.key == InputKeyBack) {
  590. app->running = 0;
  591. } else {
  592. asteroids_update_keypress_state(app, input);
  593. }
  594. } else {
  595. /* Useful to understand if the app is still alive when it
  596. * does not respond because of bugs. */
  597. if(DEBUG_MSG) {
  598. static int c = 0;
  599. c++;
  600. if(!(c % 20)) FURI_LOG_E(TAG, "Loop timeout");
  601. }
  602. }
  603. }
  604. furi_timer_free(timer);
  605. asteroids_app_free(app);
  606. return 0;
  607. }