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| -rw-r--r-- | snake.c | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/snake.c b/snake.c new file mode 100644 index 0000000..3eb28f5 --- /dev/null +++ b/snake.c @@ -0,0 +1,206 @@ +/* Copyright (C) 2021 C. McEnroe <june@causal.agency> + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU Affero General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Affero General Public License for more details. + * + * You should have received a copy of the GNU Affero General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <curses.h> +#include <stdbool.h> +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> + +typedef unsigned uint; +typedef unsigned char byte; + +enum { + Rows = 24, + Cols = 48, +}; + +static uint score; +static const char *over; + +static struct { + uint len; + byte y[Rows * Cols]; + byte x[Rows * Cols]; +} snake = { .len = 1 }; + +static struct { + int y, x; + int dy, dx; +} head = { Rows / 2, Cols / 2, 0, 1 }; + +enum { + FoodCap = 25, + FoodChance = 15, + FoodRipe = Rows + Cols, + FoodSpoil = FoodRipe + Cols, + FoodMulch = FoodSpoil * 10, +}; + +static struct { + uint len; + byte y[FoodCap]; + byte x[FoodCap]; + uint age[FoodCap]; +} food; + +static void tick(void) { + for (uint i = 0; i < food.len; ++i) { + if (head.y + head.dy != food.y[i]) continue; + if (head.x + head.dx != food.x[i]) continue; + if (food.age[i] > FoodSpoil) { + over = "You ate spoiled food!"; + return; + } + score += snake.len * (food.age[i] > FoodRipe ? 2 : 1); + food.len--; + food.y[i] = food.y[food.len]; + food.x[i] = food.x[food.len]; + food.age[i] = food.age[food.len]; + snake.len++; + break; + } + for (uint i = food.len - 1; i < food.len; --i) { + if (food.age[i]++ < FoodMulch) continue; + food.len--; + food.y[i] = food.y[food.len]; + food.x[i] = food.x[food.len]; + food.age[i] = food.age[food.len]; + } + if (!food.len || (food.len < FoodCap && !arc4random_uniform(FoodChance))) { + int y = arc4random_uniform(Rows); + int x = arc4random_uniform(Cols); + bool empty = true; + if (y == head.y && x == head.x) empty = false; + for (uint i = 0; i < snake.len; ++i) { + if (y == snake.y[i] && x == snake.x[i]) empty = false; + } + for (uint i = 0; i < food.len; ++i) { + if (y == food.y[i] && x == food.x[i]) empty = false; + } + if (empty) { + food.y[food.len] = y; + food.x[food.len] = x; + food.age[food.len] = 0; + food.len++; + } + } + for (uint i = snake.len - 1; i < snake.len; --i) { + if (i) { + snake.y[i] = snake.y[i-1]; + snake.x[i] = snake.x[i-1]; + } else { + snake.y[i] = head.y; + snake.x[i] = head.x; + } + } + head.y += head.dy; + head.x += head.dx; + if (head.y < 0 || head.x < 0 || head.y >= Rows || head.x >= Cols) { + over = "You eated the wall D:"; + } + for (uint i = 0; i < snake.len; ++i) { + if (head.y != snake.y[i] || head.x != snake.x[i]) continue; + over = "You eated yourself :("; + } +} + +enum { KeyOK = KEY_MAX + 1 }; +static void curse(void) { + initscr(); + cbreak(); + noecho(); + curs_set(0); + keypad(stdscr, true); + nodelay(stdscr, true); + define_key("\33[0n", KeyOK); + start_color(); + use_default_colors(); + init_pair(1, COLOR_GREEN, -1); + init_pair(2, COLOR_YELLOW, -1); + init_pair(3, COLOR_RED, -1); + mvhline(Rows, 0, ACS_HLINE, Cols); + mvvline(0, Cols, ACS_VLINE, Rows); + mvaddch(Rows, Cols, ACS_LRCORNER); +} + +static void draw(void) { + char buf[16]; + snprintf(buf, sizeof(buf), "%u", score); + mvaddstr(0, Cols + 2, buf); + if (over) { + mvaddstr(2, Cols + 2, over); + mvaddstr(3, Cols + 2, "Press any key to"); + mvaddstr(4, Cols + 2, "view the scoreboard."); + } + for (int y = 0; y < Rows; ++y) { + mvhline(y, 0, ' ', Cols); + } + for (uint i = 0; i < food.len; ++i) { + if (food.age[i] > FoodSpoil) { + mvaddch(food.y[i], food.x[i], '*' | COLOR_PAIR(3)); + } else if (food.age[i] > FoodRipe) { + mvaddch(food.y[i], food.x[i], '%' | COLOR_PAIR(2)); + } else { + mvaddch(food.y[i], food.x[i], '&' | COLOR_PAIR(1)); + } + } + for (uint i = 0; i < snake.len; ++i) { + mvaddch(snake.y[i], snake.x[i], '#' | COLOR_PAIR(2)); + } + mvaddch(head.y, head.x, '@' | A_BOLD); + move(head.y, head.x); + refresh(); +} + +static void input(void) { + int ch = getch(); + if (ch == ERR) { + putp("\33[5n"); + fflush(stdout); + nodelay(stdscr, false); + ch = getch(); + nodelay(stdscr, true); + } + switch (ch) { + break; case 'h': case KEY_LEFT: head.dy = 0; head.dx = -1; + break; case 'j': case KEY_DOWN: head.dy = +1; head.dx = 0; + break; case 'k': case KEY_UP: head.dy = -1; head.dx = 0; + break; case 'l': case KEY_RIGHT: head.dy = 0; head.dx = +1; + break; case 'q': over = "You are satisfied."; + break; case ERR: exit(EXIT_FAILURE); + } +} + +uint playSnake(void) { + curse(); + do { + tick(); + draw(); + usleep(150000); + input(); + } while (!over); + draw(); + while (ERR != getch()); + nodelay(stdscr, false); + getch(); + return score; +} + +int main(void) { + playSnake(); + endwin(); +} |