# Help with snake game

**URL:** <https://discourse.processing.org/t/help-with-snake-game/28328>\
**Category:** Coding Questions\
**Created:** [March 8, 2021, 6:32am UTC](https://discourse.processing.org/t/help-with-snake-game/28328 "2021-03-08T06:32:37Z")\
**Posts on this page:** 5\
**Page:** 1

<div class="post-metadata">

**Author:** ![NewProgrammer123](https://avatars.discourse-cdn.com/v4/letter/n/ecc23a/32.png) [@NewProgrammer123](https://discourse.processing.org/u/NewProgrammer123)\
**Post date:** [March 8, 2021, 6:32am UTC](https://discourse.processing.org/t/help-with-snake-game/28328/1 "2021-03-08T06:32:37Z")

</div>

Hello, I am new to programming and I’m trying to create the snake game. I have been able to create the food and the snake with some help from google but I cant seem to get the snake to move. Any help or tips would be greatly appreciated. Here is my code so far. Thank you.

```auto
int direction=0;
int size=4;
int snakeX;
int snakeY;
int time=1;

float foodX =(round(random(50)+1)*10);
float foodY =(round(random(50)+1)*10);

int[] sHeadX= new int[2500];
int[] sHeadY= new int[2500];

void setup() {
  size (500, 500);
}

void draw() {
  
  time+=1;
  background(255);
  rect(foodX, foodY, 10, 10);
  fill(0,0,0);
  rect(snakeX, snakeY, 15, 15);
  
  
   if ((time % 5)==0) //framerate
  {
    move();
    display();
  }
}

void keyPressed()
{
  if (key == CODED)
  {
    if (keyCode == UP && direction!=270 && (sHeadY[1]-8)!=sHeadY[2])
    {
      direction=90;
    }
    if (keyCode == DOWN && direction!=90 && (sHeadY[1]+8)!=sHeadY[2])
    {
      direction=270;
    }if (keyCode == LEFT && direction!=0 && (sHeadX[1]-8)!=sHeadX[2])
    {
      direction=180;
    }if (keyCode == RIGHT && direction!=180 && (sHeadX[1]+8)!=sHeadX[2])
    {
    }
    
}
}

void move(){
  
     for(int i=size;i>0;i--)
  {
    if (i!=1)
    {
      //shift back by 1 array
      sHeadX[i]=sHeadX[i-1];
      sHeadY[i]=sHeadY[i-1];
    }
    else
    {
      fill(0,0,0);
    
      //set new spot for snake head
      switch(direction)
      {
        case 0:
        sHeadX[1]+=8;
        break;
        case 90:
        sHeadY[1]-=8;
        break;
        case 180:
        sHeadX[1]-=8;
        break;
        case 270:
        sHeadY[1]+=8;
        break;
      }
    }
  }
}
void display()           
{
  if (sHeadX[1]==foodX && sHeadY[1]==foodY)
  {
    size+=round(random(3)+1);
{
    foodX=(round(random(50)+1)*10);
    foodY=(round(random(50)+1)*10);
      for(int i=1;i<size;i++)
      {     
        if (foodX==sHeadX[i] && foodY==sHeadY[i])
        {

        }
        else
        {

          i=1000;
        }
      }
    }
  }

}

```

---

<div class="post-metadata">

**Author:** ![TfGuy44](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/tfguy44/32/41_2.png) [@TfGuy44](https://discourse.processing.org/u/TfGuy44)\
**Post date:** [March 8, 2021, 7:16am UTC](https://discourse.processing.org/t/help-with-snake-game/28328/2 "2021-03-08T07:16:37Z")

</div>

In `draw()`, you are drawing one rectangle for the snake, at the position `(snakeX, snakeY)`.

The values for `snakeX` and `snakeY` are never assigned any values! Like, at all! And since these values never change (at all) the snake’s rectangle never moves (at all)!

I think you’ve bitten off too much at once. Forget about a snake for now, forget about using an array to track all the positions for it, and just work on getting a single square moving about.

Or go wild and draw all the segments of you snake using a for loop and the arrays you have that are storing the values for the actual snake’s position.

---

<div class="post-metadata">

**Author:** ![micuat](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/micuat/32/19407_2.png) [@micuat](https://discourse.processing.org/u/micuat)\
**Post date:** [March 8, 2021, 7:21am UTC](https://discourse.processing.org/t/help-with-snake-game/28328/3 "2021-03-08T07:21:26Z")

</div>

I agree and it’s good to do it step by step. Dan’s tutorial might help too

> **[The Snake Game](https://thecodingtrain.com/CodingChallenges/003-snake-game-p5.html)**
>
> In this coding challenge, I attempt to code a p5.js version of the Snake Game.

---

<div class="post-metadata">

**Author:** ![TfGuy44](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/tfguy44/32/41_2.png) [@TfGuy44](https://discourse.processing.org/u/TfGuy44)\
**Post date:** [March 8, 2021, 7:22am UTC](https://discourse.processing.org/t/help-with-snake-game/28328/4 "2021-03-08T07:22:48Z")

</div>

I also have some sample snake code myself, which I think is quite good, but doesn’t do snake-snake collision detecting. If you’re down with classes, this might be easier to use as a starting point:

```auto
// Useful arrays to decode/use direction.
int[] dx = {1, 0, -1, 0};
int[] dy = {0, 1, 0, -1};
int[] dk = { RIGHT, DOWN, LEFT, UP };

class Snake {
  int x, y; // Current head position.
  ArrayList<PVector> tail; // Other segments.
  int d; // Direction of movement;
  boolean isGrowing = false;
  Snake() {
    d = 0;
    tail = new ArrayList();
  }
  void draw() {
    fill(50,200,50);
    stroke(150,200,50);
    rect(x,y,20,20);
    for( int i = 0; i < tail.size(); i++){
      rect(tail.get(i).x,tail.get(i).y,20,20);
    }
  }
  void update() {
    tail.add( new PVector(x,y,d) );
    if( isGrowing ){
      isGrowing = false;
    } else {
      tail.remove(0);
    }
    x += 20*dx[d];
    y += 20*dy[d];
    x += width;
    y += height;
    x %= width;
    y %= height;
  }
  void grow() {
    isGrowing = true;
  }
  void onKeyPressed() {
    for( int i = 0; i < dk.length; i++){
      if( key == CODED && keyCode == dk[i] ){
        d = i;
      }
    }
  }
}

class Food {
  int x, y;
  Food() {
    newPosition();
  }
  void draw() {
    fill(255,0,0);
    stroke(200,0,200);
    ellipse(x+10,y+10,20,20);
  }
  boolean wasEaten(int ox, int oy) {
    if ( x == ox && y == oy ) {
      newPosition();
      return true;
    }
    return false;
  }
  void newPosition() {
    x = 20 * int(random(width/20));
    y = 20 * int(random(height/20));
  }
}

class Timer {
  int time;
  int duration;
  Timer() {
    duration = 100;
    reset();
  }
  void reset() {
    time = millis() + duration;
  }
  boolean alarm() {
    if ( millis() > time ) {
      time = millis() + duration;
      return true;
    }
    return false;
  }
}

// --- Main driving code follows. Notice how simple its logic is to understand!

Snake snake;
Food food;
Timer timer;

void setup() {
  size(600, 400);
  snake = new Snake();
  food = new Food();
  timer = new Timer();
}

void draw() {
  background(0);
  if ( timer.alarm() ) {
    snake.update();
    if ( food.wasEaten( snake.x, snake.y ) ) {
      snake.grow();
    }
  }
  food.draw();
  snake.draw();
}

void keyPressed() {
  snake.onKeyPressed();
}

```

YMMV

---

<div class="post-metadata">

**Author:** ![NewProgrammer123](https://avatars.discourse-cdn.com/v4/letter/n/ecc23a/32.png) [@NewProgrammer123](https://discourse.processing.org/u/NewProgrammer123)\
**Post date:** [March 10, 2021, 7:56am UTC](https://discourse.processing.org/t/help-with-snake-game/28328/5 "2021-03-10T07:56:44Z")

</div>

Ok, I’ve started again and this is what I’ve come up with. I am still having some issues with getting it to move. TfGuy44 you said to forget about using arrays but I have tried searching and coming up with solutions but cant find any without using it. Please correct me if I’m wrong but I’m imagining the program to draw a new rectangle at a new position which gets added to the array which I am having trouble with. Then some code which essentially gets the position of the snake -1 to remove it.  
I also keep getting this error

> The method rect(float, float, float, float) in the type PApplet is not applicable for the arguments (float, float, float, float)

```auto
int width = 10;
int height = 10;
int size = 10;
float [] snakeX = new float [10];
float [] snakeY = new float [10];
int direction = 0;

void setup() {
  size(400,400);
}

void draw(){
 background(255);
 
 fill(0);
 rect(snakeX,snakeY,10,10);
 }
 
 
 void keyPressed()
{
  if (key == CODED)
  {
    if (keyCode == UP && direction!=270 && (snakeY[1]-8)!=snakeY[2])
    {
      direction=90;
    }
    if (keyCode == DOWN && direction!=90 && (snakeY[1]+8)!=snakeY[2])
    {
      direction=270;
    }if (keyCode == LEFT && direction!=0 && (snakeX[1]-8)!=snakeX[2])
    {
      direction=180;
    }if (keyCode == RIGHT && direction!=180 && (snakeX[1]+8)!=snakeX[2])
    {
    }
    
}
}

```