let playerPositionX = 300;

let playerPositionY = 300;

let enemyPositionX = 0;

let enemyPositionY = 0;

let direction = null;

let velocity = 1;

let gameOver = false;

​

function setup() {

  // setup the random initial location of the enemy

  enemyPositionX = random(500);

  enemyPositionY = random(500);

  createCanvas(500, 500);

}

​

function draw() {

  // Game over?

  if (gameOver) {

    fill(200,50,40);

    textSize(20);

    text("GAME OVER", 200,250); 

    return; // just skip everything else

  }

  // Hit a wall?

  if (playerPositionX < 0 || playerPositionX > 500 || playerPositionY < 0 || playerPositionY > 500) {

   gameOver = true; 

  }

  // get distance of the two circles using Pythagoras

  let distance = sqrt(pow(playerPositionX -enemyPositionX ,2) + pow(playerPositionY - enemyPositionY, 2));

  // get the sum of the two radii (note we pass the diameter to the circle function, so we need to half it!)

  let radii = 10 + playerWeight / 2;

  // check if the distance is smaller than the sum

  let collisionDetected = distance <= radii;

  if (collisionDetected) {

    playerWeight += 2;

    velocity += 1;

    enemyPositionX = random(500);

    enemyPositionY = random(500);

  }

  // Update the world

  if (direction == 'up') {

    playerPositionY = playerPositionY - velocity; 

  }

  if (direction == 'left') {

    playerPositionX = playerPositionX - velocity; 

  }

  if (direction == 'right') {

    playerPositionX = playerPositionX + velocity; 

  }

  if (direction == 'down') {

    playerPositionY = playerPositionY + velocity; 

  }

  // draw a black background

  background(0);

​

  // define the fill color for the player

  fill(255, 120, 90);

  // draw a circle (our player)

  circle(playerPositionX, playerPositionY, playerWeight);

​

  // define the fill color of the enemy

  fill(0, 255, 0);

  // draw the enemy as a circle

  circle(enemyPositionX, enemyPositionY, 20);

  // current score

  fill(60,200,120);

  textSize(20);

  text("your current weight " + playerWeight + " kg",20,20);

}

​

function keyPressed() {

  if (key == 'w') {

    direction = 'up';

  }

  if (key == 'a') {

    direction = 'left';

  }

  if (key == 's') {

    direction = 'down';

  }

  if (key == 'd') {

    direction = 'right';

  }

}