Greedy Snake Game

This example implements the classic Snake game on an 8x12 LED matrix using the R4 Wifi board. Players control the snake’s direction using a dual-axis joystick.

Wiring

Schematic

Code

Note

• You can open the file 20_Greedy_Snake_Game.ino under the path of Basic-Starter-Kit-for-Arduino-Uno-R4-WiFi-main\Code directly.

How it works?

1. Include Libraries

   Include the necessary library for the LED matrix.

   #include "Arduino_LED_Matrix.h"
   

2. Initialize Variables

   Define and initialize variables for the LED matrix, snake, and food.

   ArduinoLEDMatrix matrix;
   byte frame[8][12];
   byte flatFrame[8 * 12];
   
   struct Point {
     byte x;
     byte y;
   };
   
   Point snake[100];
   int snakeLength = 3;
   Point food;
   int direction = 0;
   

3. Setup Function

   Initialize the joystick and LED matrix. Set initial snake position and generate food.

   void setup() {
     pinMode(A0, INPUT);
     pinMode(A1, INPUT);
   
     matrix.begin();
   
     snake[0] = { 6, 4 };
     snake[1] = { 6, 5 };
     snake[2] = { 6, 6 };
   
     generateFood();
   }
   

4. Main Loop

   Read joystick input, update snake direction, move snake, check for collisions, and update the display.

   void loop() {
     int x = analogRead(A0);
     int y = analogRead(A1);
   
     if (x > 600 && direction != 3) direction = 1;
     else if (x < 400 && direction != 1) direction = 3;
     else if (y > 600 && direction != 0) direction = 2;
     else if (y < 400 && direction != 2) direction = 0;
   
     moveSnake();
   
     if (snake[0].x == food.x && snake[0].y == food.y) {
       snake[snakeLength] = snake[snakeLength - 1];
       snakeLength++;
       generateFood();
     }
   
     for (int i = 1; i < snakeLength; i++) {
       if (snake[0].x == snake[i].x && snake[0].y == snake[i].y) {
         snakeLength = 3;
         snake[0] = { 6, 4 };
         snake[1] = { 6, 5 };
         snake[2] = { 6, 6 };
         direction = 0;
         generateFood();
       }
     }
   
     drawFrame();
     delay(200);
   }
   

5. Move Snake

   Update the snake’s position based on the direction.

   void moveSnake() {
     for (int i = snakeLength - 1; i > 0; i--) {
       snake[i] = snake[i - 1];
     }
   
     switch (direction) {
       case 0:
         snake[0].y = (snake[0].y - 1 + 8) % 8;
         break;
       case 1:
         snake[0].x = (snake[0].x + 1) % 12;
         break;
       case 2:
         snake[0].y = (snake[0].y + 1) % 8;
         break;
       case 3:
         snake[0].x = (snake[0].x - 1 + 12) % 12;
         break;
     }
   }
   

6. Generate Food

   Generate a new food position that doesn’t overlap with the snake.

   void generateFood() {
     Point possibleLocations[8 * 12];
     int idx = 0;
   
     for (int y = 0; y < 8; y++) {
       for (int x = 0; x < 12; x++) {
         bool overlap = false;
   
         for (int i = 0; i < snakeLength; i++) {
           if (snake[i].x == x && snake[i].y == y) {
             overlap = true;
             break;
           }
         }
   
         if (!overlap) {
           possibleLocations[idx++] = { x, y };
         }
       }
     }
   
     int choice = random(0, idx);
     food = possibleLocations[choice];
   }
   

7. Draw Frame

   Draw the current state of the snake and food on the LED matrix.

   void drawFrame() {
     for (int y = 0; y < 8; y++) {
       for (int x = 0; x < 12; x++) {
         frame[y][x] = 0;
       }
     }
   
     for (int i = 0; i < snakeLength; i++) {
       frame[snake[i].y][snake[i].x] = 1;
     }
   
     frame[food.y][food.x] = 1;
   
     int idx = 0;
     for (int y = 0; y < 8; y++) {
       for (int x = 0; x < 12; x++) {
         flatFrame[idx++] = frame[y][x];
       }
     }
     matrix.loadPixels(flatFrame, 8 * 12);
     matrix.renderFrame(0);
   }