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examples/game/01-snake: Remove RNG abstraction.

This commit is contained in:
Ryan C. Gordon 2024-08-30 17:13:51 -04:00
parent 29b9b163b9
commit c38d3f0fe4
No known key found for this signature in database
GPG Key ID: FA148B892AB48044
1 changed files with 12 additions and 14 deletions
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26
examples/game/01-snake/snake.c
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@ -53,8 +53,6 @@ typedef struct
unsigned occupied_cells; unsigned occupied_cells;
} SnakeContext; } SnakeContext;
typedef Sint32 (SDLCALL *RandFunc)(Sint32 n);
typedef struct typedef struct
{ {
SDL_Window *window; SDL_Window *window;
@ -94,11 +92,11 @@ static int are_cells_full_(SnakeContext *ctx)
return ctx->occupied_cells == SNAKE_GAME_WIDTH * SNAKE_GAME_HEIGHT; return ctx->occupied_cells == SNAKE_GAME_WIDTH * SNAKE_GAME_HEIGHT;
} }
static void new_food_pos_(SnakeContext *ctx, RandFunc rand) static void new_food_pos_(SnakeContext *ctx)
{ {
while (SDL_TRUE) { while (SDL_TRUE) {
const char x = (char) rand(SNAKE_GAME_WIDTH); const char x = (char) SDL_rand(SNAKE_GAME_WIDTH);
const char y = (char) rand(SNAKE_GAME_HEIGHT); const char y = (char) SDL_rand(SNAKE_GAME_HEIGHT);
if (snake_cell_at(ctx, x, y) == SNAKE_CELL_NOTHING) { if (snake_cell_at(ctx, x, y) == SNAKE_CELL_NOTHING) {
put_cell_at_(ctx, x, y, SNAKE_CELL_FOOD); put_cell_at_(ctx, x, y, SNAKE_CELL_FOOD);
break; break;
@ -106,7 +104,7 @@ static void new_food_pos_(SnakeContext *ctx, RandFunc rand)
} }
} }
void snake_initialize(SnakeContext *ctx, RandFunc rand) void snake_initialize(SnakeContext *ctx)
{ {
int i; int i;
SDL_zeroa(ctx->cells); SDL_zeroa(ctx->cells);
@ -117,7 +115,7 @@ void snake_initialize(SnakeContext *ctx, RandFunc rand)
--ctx->occupied_cells; --ctx->occupied_cells;
put_cell_at_(ctx, ctx->tail_xpos, ctx->tail_ypos, SNAKE_CELL_SRIGHT); put_cell_at_(ctx, ctx->tail_xpos, ctx->tail_ypos, SNAKE_CELL_SRIGHT);
for (i = 0; i < 4; i++) { for (i = 0; i < 4; i++) {
new_food_pos_(ctx, rand); new_food_pos_(ctx);
++ctx->occupied_cells; ++ctx->occupied_cells;
} }
} }
@ -142,7 +140,7 @@ static void wrap_around_(char *val, char max)
} }
} }
void snake_step(SnakeContext *ctx, RandFunc rand) void snake_step(SnakeContext *ctx)
{ {
const SnakeCell dir_as_cell = (SnakeCell)(ctx->next_dir + 1); const SnakeCell dir_as_cell = (SnakeCell)(ctx->next_dir + 1);
SnakeCell ct; SnakeCell ct;
@ -194,17 +192,17 @@ void snake_step(SnakeContext *ctx, RandFunc rand)
/* Collisions */ /* Collisions */
ct = snake_cell_at(ctx, ctx->head_xpos, ctx->head_ypos); ct = snake_cell_at(ctx, ctx->head_xpos, ctx->head_ypos);
if (ct != SNAKE_CELL_NOTHING && ct != SNAKE_CELL_FOOD) { if (ct != SNAKE_CELL_NOTHING && ct != SNAKE_CELL_FOOD) {
snake_initialize(ctx, rand); snake_initialize(ctx);
return; return;
} }
put_cell_at_(ctx, prev_xpos, prev_ypos, dir_as_cell); put_cell_at_(ctx, prev_xpos, prev_ypos, dir_as_cell);
put_cell_at_(ctx, ctx->head_xpos, ctx->head_ypos, dir_as_cell); put_cell_at_(ctx, ctx->head_xpos, ctx->head_ypos, dir_as_cell);
if (ct == SNAKE_CELL_FOOD) { if (ct == SNAKE_CELL_FOOD) {
if (are_cells_full_(ctx)) { if (are_cells_full_(ctx)) {
snake_initialize(ctx, rand); snake_initialize(ctx);
return; return;
} }
new_food_pos_(ctx, rand); new_food_pos_(ctx);
++ctx->inhibit_tail_step; ++ctx->inhibit_tail_step;
++ctx->occupied_cells; ++ctx->occupied_cells;
} }
@ -229,7 +227,7 @@ static int handle_key_event_(SnakeContext *ctx, SDL_Scancode key_code)
return SDL_APP_SUCCESS; return SDL_APP_SUCCESS;
/* Restart the game as if the program was launched. */ /* Restart the game as if the program was launched. */
case SDL_SCANCODE_R: case SDL_SCANCODE_R:
snake_initialize(ctx, SDL_rand); snake_initialize(ctx);
break; break;
/* Decide new direction of the snake. */ /* Decide new direction of the snake. */
case SDL_SCANCODE_RIGHT: case SDL_SCANCODE_RIGHT:
@ -297,7 +295,7 @@ SDL_AppResult SDL_AppInit(void **appstate, int argc, char *argv[])
return SDL_APP_FAILURE; return SDL_APP_FAILURE;
} }
snake_initialize(&as->snake_ctx, SDL_rand); snake_initialize(&as->snake_ctx);
as->step_timer = SDL_AddTimer(STEP_RATE_IN_MILLISECONDS, sdl_timer_callback_, NULL); as->step_timer = SDL_AddTimer(STEP_RATE_IN_MILLISECONDS, sdl_timer_callback_, NULL);
if (as->step_timer == 0) { if (as->step_timer == 0) {
@ -314,7 +312,7 @@ SDL_AppResult SDL_AppEvent(void *appstate, const SDL_Event *event)
case SDL_EVENT_QUIT: case SDL_EVENT_QUIT:
return SDL_APP_SUCCESS; return SDL_APP_SUCCESS;
case SDL_EVENT_USER: case SDL_EVENT_USER:
snake_step(ctx, SDL_rand); snake_step(ctx);
break; break;
case SDL_EVENT_KEY_DOWN: case SDL_EVENT_KEY_DOWN:
return handle_key_event_(ctx, event->key.scancode); return handle_key_event_(ctx, event->key.scancode);