snake_c

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Small snake game in C

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6 commits 2 branches 1 tag 0 releases565.5 KiB

Commit `7b30379da950`

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Jaglekon <58274093+Jaglekon@users.noreply.github.com>2026-03-21 22:51 UTC

2 files changed+214-87

variable term size

Added file: art.txt+9 additions@@ -0,0 +1,9 @@
+
+
+               ________
+             _/ _      \_________
+    ________/  (_)       \      /
+    \       \             \    / 
+    /_______/   _          \  /  
+            \_ (_)      ____\/___
+              \________/

Modified file: snake.c+205 additions−87 deletions@@ -1,22 +1,31 @@
 #include <unistd.h>
+#include <termios.h>
 
 #include <stdio.h>
 #include <stdint.h>
 #include <stdbool.h>
 #include <stdlib.h>
 
+#include <sys/ioctl.h>
+
 #include <time.h>
 #include <sys/time.h>
+
 #include <string.h>
-#include <termios.h>
+#include <ctype.h>
+
 
 #define RIGHT_CODE 'C'
 #define LEFT_CODE 'D'
 #define UP_CODE 'A'
 #define DOWN_CODE 'B'
 
-#define WIDTH 50
-#define HEIGHT 50
+#define WIDTH 20
+#define HEIGHT 20
+
+#define ACTUAL_WIDTH ((WIDTH * 2) + 2)
+#define ACTUAL_HEIGHT (HEIGHT + 2)
+
 
 #define SPEED 100 /* in ms */
 
@@ -42,16 +51,43 @@ typedef struct snake {
 } snake;
 
 
+
+
 void update_field(snake my_snake, field_content board[HEIGHT][WIDTH], selected fruit);
 selected new_fruit(field_content board[HEIGHT][WIDTH]);
 
-void draw_board(field_content board[HEIGHT][WIDTH], bool redraw);
-void draw_pause();
+void draw_board(field_content board[HEIGHT][WIDTH], struct winsize window_size);
+void draw_pause(struct winsize window_size);
 
 direction read_direction (char* string, direction shift);
 
 
-int main() {
+
+int main(int argc, char *args[]) {
+
+  if (argc > 1) {
+    if (argc > 2) {
+      printf("Too many parameters\n");
+      goto help_info;
+    }
+
+    if (!strcmp(args[1], "-h") || !strcmp(args[1], "--help")) {
+
+      printf("This is a small TUI snake game.\n\n");
+      printf("Controls: Arrow keys/WASD to control the snake.\n");
+      printf("          P to pause.\n");
+      printf("          Q to quit.\n");
+
+      return 0;
+    }
+
+    printf("Argument \"%s\" not recognized\n", args[1]);
+
+  help_info:
+    printf("Try \"-h\" or \"--help\" for more information\n");
+    return 1;
+  }
+
 
   struct termios old, new;
 
@@ -67,6 +103,8 @@ int main() {
 
   srand(time(NULL));
 
+  printf("\033[?25l");
+
 
   snake my_snake = {};  
   my_snake.length = STARTING_LENGTH;
@@ -83,112 +121,158 @@ int main() {
   }
 
   selected fruit = {-1, -1};
-
   field_content board[HEIGHT][WIDTH] = {0};
-
+  
   update_field(my_snake, board, fruit);
-
+  
   fruit = new_fruit(board);
   update_field(my_snake, board, fruit);
 
+  bool paused = false;
 
-  printf("\033[?25l");
-  draw_board(board, false);
 
+  struct winsize init_size, current_size;
+  ioctl(STDOUT_FILENO, TIOCGWINSZ, &init_size);
+  current_size = init_size;
+
+  bool too_small = false;
+  
+
+  if (current_size.ws_row < ACTUAL_HEIGHT || current_size.ws_col < ACTUAL_WIDTH) {
+    too_small = true;
+    paused = true;
+
+    printf("\033[2J\033[HToo small\n");
+    printf("Min width: %i & Min height: %i\n", ACTUAL_WIDTH, ACTUAL_WIDTH);
+  } else {
+    draw_board(board, current_size);
+  }
 
   direction shift = RIGHT;
+  direction tmp_direction = shift;
 
 
   struct timeval start, current;
-
   gettimeofday(&start, NULL);
 
 
-  bool paused = false;
   bool run = true;
 
   while (run) {
 
-    char string[1000] = {};
-    ssize_t n = read(STDIN_FILENO, string, sizeof(string) - 1);
-    
-    gettimeofday(&current, NULL);
 
-    if (n > 0) {
-      string[n] = '\0';
-  
-      if (!paused)
-        shift = read_direction(string, shift);
+    if (!too_small) {
+      char string[1000] = {};
+      ssize_t length_string = read(STDIN_FILENO, string, sizeof(string) - 1);
+      
+      gettimeofday(&current, NULL);
+
+      if (length_string > 0) {
+        string[length_string] = '\0';
+    
+        if (!paused)
+          tmp_direction = read_direction(string, shift);
 
-      if (strstr(string, "q"))
-        run = false;
+        if (toupper(string[0]) == 'Q')
+          run = false;
 
-       if (strstr(string, "p")) {
-          paused = !paused;
-          if (paused)
-            draw_pause();
+         if (toupper(string[0]) == 'P') {
+            paused = !paused;
+        }
       }
+
+      if (paused)
+        draw_pause(current_size);
     }
 
+
     uint64_t time_diff = (current.tv_sec - start.tv_sec) * 1000000 + (current.tv_usec - start.tv_usec);
 
-    if ((time_diff >= SPEED * 1000) && !paused) {
+    if (time_diff >= SPEED * 1000) {
+     
+      ioctl(STDOUT_FILENO, TIOCGWINSZ, &current_size);
       
-      start = current;
-
-      uint16_t i;
-      for (i = my_snake.length; i > 0; i--) {
-        my_snake.position[i].y = my_snake.position[i - 1].y;
-        my_snake.position[i].x = my_snake.position[i - 1].x;
+      if (
+        current_size.ws_col != init_size.ws_col || 
+        current_size.ws_row != init_size.ws_row
+      ) {
+        init_size = current_size;
+        
+        paused = true;
+        
+        if (current_size.ws_row < ACTUAL_HEIGHT || current_size.ws_col < ACTUAL_WIDTH) {
+          too_small = true;
+          
+          printf("\033[2J\033[HToo small\n");
+          printf("Min width: %i & Min height: %i\n", ACTUAL_WIDTH, ACTUAL_WIDTH);
+        } else {
+          too_small = false;
+          
+          draw_board(board, current_size);
+        }
       }
 
-      switch (shift) {
-        case UP:
-          my_snake.position[0].y = ((my_snake.position[0].y + HEIGHT - 1) % HEIGHT);
-          break;
-        case DOWN:
-          my_snake.position[0].y = ((my_snake.position[0].y + 1) % HEIGHT);
-          break;
-        case LEFT:
-          my_snake.position[0].x = ((my_snake.position[0].x + WIDTH - 1) % WIDTH);
-          break;
-        case RIGHT:
-          my_snake.position[0].x = ((my_snake.position[0].x + 1) % WIDTH);
-          break;
-      }
-    
-      uint8_t head_y = my_snake.position[0].y;
-      uint8_t head_x = my_snake.position[0].x;
-
-      for (i = 1; i < my_snake.length; i++) {
-        int16_t x = my_snake.position[i].x;
-        int16_t y = my_snake.position[i].y;
-
-        if (
-          x == head_x && 
-          y == head_y
-        ) {
-          printf("\n\nHAHA LOST!!!\n\n");
-          goto end_of_program;
+      if (!paused) {
+     
+        start = current;
+        shift = tmp_direction;
+
+        uint16_t i;
+        for (i = my_snake.length; i > 0; i--) {
+          my_snake.position[i].y = my_snake.position[i - 1].y;
+          my_snake.position[i].x = my_snake.position[i - 1].x;
         }
-      }
 
-      if (head_y == fruit.y && head_x == fruit.x) {
-        my_snake.length++;
-        fruit = new_fruit(board);
-      }
+        switch (shift) {
+          case UP:
+            my_snake.position[0].y = ((my_snake.position[0].y + HEIGHT - 1) % HEIGHT);
+            break;
+          case DOWN:
+            my_snake.position[0].y = ((my_snake.position[0].y + 1) % HEIGHT);
+            break;
+          case LEFT:
+            my_snake.position[0].x = ((my_snake.position[0].x + WIDTH - 1) % WIDTH);
+            break;
+          case RIGHT:
+            my_snake.position[0].x = ((my_snake.position[0].x + 1) % WIDTH);
+            break;
+        }
+      
+        uint8_t head_y = my_snake.position[0].y;
+        uint8_t head_x = my_snake.position[0].x;
+
+        for (i = 1; i < my_snake.length; i++) {
+          int16_t x = my_snake.position[i].x;
+          int16_t y = my_snake.position[i].y;
+
+          if (
+            x == head_x && 
+            y == head_y
+          ) {
+            printf("\n\nHAHA LOST!!!\n\n");
+            goto end_of_program;
+          }
+        }
 
+        update_field(my_snake, board, fruit);
 
-      update_field(my_snake, board, fruit);
-      draw_board(board, true);
-    }
+        if (head_y == fruit.y && head_x == fruit.x) {
+          my_snake.length++;
+          fruit = new_fruit(board);
+        }
 
+
+        update_field(my_snake, board, fruit);
+        draw_board(board, current_size);
+      }
+    }
   }
 
+
 end_of_program:
 
   tcsetattr(STDIN_FILENO, TCSANOW, &old);
-  printf("\033[?25h");
+  printf("\033[?25h\n\n");
 
   return 0;
 }
@@ -233,22 +317,26 @@ selected new_fruit(field_content board[HEIGHT][WIDTH]) {
       found_space = true;
   }
 
-  selected fruit = {y, x};
+  selected fruit = {x, y};
 
   return fruit;
 }
 
 
-void draw_board (field_content board[HEIGHT][WIDTH], bool redraw) {
+void draw_board (field_content board[HEIGHT][WIDTH], struct winsize window_size) {
   
   uint8_t i, j; 
 
-  if (redraw) {
-    for (i = 0; i < HEIGHT + 2; i++)
-      printf("\033[A");
-    printf("\r");
-  }
+  uint8_t vertical_buffer = (window_size.ws_row - ACTUAL_HEIGHT) >> 1;
+  uint8_t horizontal_buffer = (window_size.ws_col - ACTUAL_WIDTH) >> 1;
+
+  printf("\033[2J\033[H");
 
+  for (i = 0; i < vertical_buffer; i++)
+    printf("\n");
+
+  for (i = 0; i < horizontal_buffer; i++)
+      printf(" ");
   printf("+");
   for (i = 0; i < WIDTH; i++)
     printf("--");
@@ -256,6 +344,9 @@ void draw_board (field_content board[HEIGHT][WIDTH], bool redraw) {
 
   for ( i = 0; i < HEIGHT; i++) {
 
+    for (j = 0; j < horizontal_buffer; j++)
+      printf(" ");
+
     printf("|");
 
     for (j = 0; j < WIDTH; j++) {
@@ -278,19 +369,22 @@ void draw_board (field_content board[HEIGHT][WIDTH], bool redraw) {
     printf("|\n");
   }
 
-    printf("+");
+  for (i = 0; i < horizontal_buffer; i++)
+    printf(" ");
+  printf("+");
   for (i = 0; i < WIDTH; i++)
     printf("--");
-  printf("+\n");
+  printf("+");
+  fflush(stdout);
 }
 
 
-void draw_pause() {
+void draw_pause(struct winsize window_size) {
 
   const uint8_t height = 5;
   const uint8_t width = 14;
 
-  char *pause_menu [] = {
+  const char *pause_menu [] = {
     "+------------+",
     "|            |",
     "|   PAUSED   |",
@@ -298,16 +392,21 @@ void draw_pause() {
     "+------------+"
   };
 
-  uint8_t i, j;
 
-  const uint8_t going_up = (HEIGHT + height) >> 1;
-  const uint8_t going_right = (WIDTH * 2 - width) >> 1;
+  const uint8_t going_up = (ACTUAL_HEIGHT + height) >> 1;
+  const uint8_t going_right = (ACTUAL_WIDTH - width) >> 1;
+
+  const uint8_t horizontal_buffer = (window_size.ws_col - ACTUAL_WIDTH) >> 1;
+
+  uint8_t i, j;
 
   for (i = 0; i < going_up; i++)
     printf("\033[%c", UP_CODE);
   printf("\r");
 
   for (i = 0; i < height; i++) {
+    for (j = 0; j < horizontal_buffer; j++)
+      printf("\033[%c", RIGHT_CODE);
     for (j = 0; j < going_right; j++)
       printf("\033[%c", RIGHT_CODE);
 
@@ -321,7 +420,6 @@ void draw_pause() {
   fflush(stdout);
 }
 
-
 direction read_direction (char* string, direction shift) {
 
   if (strlen(string) >= 3) {
@@ -350,5 +448,25 @@ direction read_direction (char* string, direction shift) {
     }
   }
 
+
+  switch (toupper(string[0])) {
+    case 'A':
+      if (shift != RIGHT)
+        return LEFT;
+      break;
+    case 'D':
+      if (shift != LEFT)
+        return RIGHT;
+      break;
+    case 'W':
+      if (shift != DOWN)
+        return UP;
+      break;
+    case 'S':
+      if (shift != UP)
+        return DOWN;
+      break;
+  }
+
   return shift;
 }

snake_c

Commit 7b30379da950

Commit `7b30379da950`