小行星游戏

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html

 
<script src="http://cdnjs.cloudflare.com/ajax/libs/p5.js/0.4.10/p5.min.js"></script>

css

​x
 
canvas {
    display: block;
} 
​
body {
  padding: 0;
  margin: 0;
  background-color: #FFFFFF;
}

JavaScript

var ship;
var asteroids = [];
var astnum;
var initastnum = 2;
var debris = [];
var energy = [];
var gameLevel = 0;
var message;

function setup() {
  createCanvas(windowWidth, windowHeight);
  textFont("Courier");
  ship = new Ship();
  initialize("let's play!", initastnum);
}

function draw() {
  background(0);
  for (var i = debris.length - 1; i >= 0; i--) {
    debris[i].update();
    debris[i].render();
    if (debris[i].transparency <= 0) {
      debris.splice(i, 1);
    }
  }

for (var i = energy.length - 1; i >= 0; i--) {
    energy[i].update();
    energy[i].render();
    energy[i].edges();
    if (ship.hit(energy[i]) && !ship.safe) {
      ship.safe = true;
      setTimeout(function() {
        ship.safe = !ship.safe;
      }, 2000);
      ship.getBonus();
      energy[i].alive = false;
    };
    if (energy[i].life <= 20) {
      energy[i].alive = false;
    };
    if (!energy[i].alive) {
      energy.splice(i, 1);
    };
  }

if (ship.alive) {
    ship.update();
    ship.render();
    ship.edges();
  } else {
    console.log("Game Over");
    message = "Game Over";
    //restart();
  };

if (asteroids.length == 0) { // player cleared the level
    astnum += 3;
    initialize("You Win! Level up!", astnum);
  }

for (var i = asteroids.length - 1; i >= 0; i--) {
    asteroids[i].render();
    asteroids[i].update();
    asteroids[i].edges();
    if (ship.hit(asteroids[i]) && !ship.safe) {
      ship.danger = true;
      setTimeout(function() {
        ship.danger = !ship.danger;
      }, 100);
      ship.getDamage(asteroids[i]);
      console.log("Damaging the shield " + ship.shieldLevel);
      asteroids[i].explode();
      asteroids.splice(i, 1);
      //console.log(asteroids.length);
      //ship.explode();
    }
  }

//interface info
  ship.interface();
  }

function initialize(messageText, newastnum) {
    message = messageText;
    gameLevel += 1;
    astnum = newastnum;
    basicinit();
  }

function restart(messageText, newastnum) {
    ship.init();
    gameLevel = 1;
    asteroids = [];
    energy = [];
    message = messageText;
    astnum = newastnum;
    basicinit();
  }

function keyReleased() {
    if (keyCode == RIGHT_ARROW || keyCode == LEFT_ARROW) {
      ship.setRotation(0);
    } else if (keyCode == UP_ARROW) {
      ship.boosting = false;
    }
  }

function windowResized() {
    resizeCanvas(windowWidth, windowHeight);
}

/////// SHIP Class

function Ship() {
  this.pos = createVector(width / 2, height / 2 + 50);
  this.vel = createVector(0, 0);
  this.r = 10;
  this.heading = 0;
  this.rotation = 0;
  this.boosting = false;
  this.lasers = [];
  this.shieldLevel = 100;
  this.shieldMax = 200;
  this.alive = true;
  this.danger = false;
  this.safe = true;
  this.score = 0;
}

Ship.prototype.interface = function() {
  textSize(14);
  fill(255);
  noStroke();
  text("Score = " + this.score, 50, 50);
  //text("Shield = " + constrain(round(ship.shieldLevel), 0, 100), 50, 65);
  if (this.shieldLevel >= this.shieldMax) {
    text("Shield = Max!", 50, 65);
  } else {
    text("Shield = " + constrain(round(this.shieldLevel), 0, round(this.shieldLevel)), 50, 65);
  }
  text("Level = " + gameLevel, 50, 80);
  if (message) {
    textSize(32);
    text(message, width / 2 - message.length * 10, height / 2);
  }
}

Ship.prototype.init = function() {
  this.pos = createVector(width / 2, height / 2 + 50);
  this.vel = createVector(0, 0);
  ship.alive = true;
  ship.score = 0;
  ship.shieldLevel = 100;
}

Ship.prototype.hit = function(obj) {
  var d = dist(this.pos.x, this.pos.y, obj.pos.x, obj.pos.y);
  if (d < this.r + obj.r) {
    return true;
  } else {
    return false;
  }
}

Ship.prototype.getDamage = function(obj) {
  var damount = obj.r; // the bigger the object hitting the ship the heavier the damage amount
  this.shieldLevel -= damount;
  if (this.shieldLevel <= 0) {
    this.explode();
  }
}

Ship.prototype.getBonus = function() {
  this.shieldLevel += 30;
  this.score += 20;
  this.shieldLevel = constrain(this.shieldLevel, 0, this.shieldMax);
}

Ship.prototype.explode = function() {
  var debrisVel = p5.Vector.random2D().mult(random(0.5, 1.5));
  //var debrisVel = p5.Vector.add(this.lasers[i].vel.mult(0.2), asteroids[j].vel);
  var debrisNum = 50;
  generateDebris(this.pos, debrisVel, debrisNum); // handeling ship explosion
  this.alive = false;
}

Ship.prototype.update = function() {
  this.pos.add(this.vel);
  this.vel.mult(0.99); // simulating friction
  this.turn();
  if (this.boosting) {
    this.boost();
  }
  for (var i = this.lasers.length - 1; i >= 0; i--) {
    this.lasers[i].render();
    this.lasers[i].update();
    //console.log(this.lasers.length);
    if (this.lasers[i].offscreen()) { // cleaning up my laser beam array when beams are out off the screen
      this.lasers.splice(i, 1);
      //console.log(this.lasers.length);
    } else {
      for (var j = asteroids.length - 1; j >= 0; j--) {
        if (this.lasers[i].hits(asteroids[j])) {
          console.log("asteroid number " + j + " has been hitted! " + asteroids.length);
          var debrisVel = p5.Vector.add(this.lasers[i].vel.mult(0.2), asteroids[j].vel);
          var debrisNum = (asteroids[j].r) * 5;
          generateDebris(asteroids[j].pos, debrisVel, debrisNum); // handeling asteroids explosions
          var newAsteroids = asteroids[j].breakup(); // returns an array of two smaller asteroids
          if (newAsteroids.length > 0) {
            //console.log(newAsteroids);
            //asteroids.push(newAsteroids[0]); //asteroids.push(newAsteroids[1]);
            var probability = random() * 100;
            if (probability > 80) {
              //console.log("Shupershield!!!!");
              generateEnergy(asteroids[j].pos, debrisVel);
            }
            asteroids = asteroids.concat(newAsteroids); // concatenating (merging) arrays // https://www.w3schools.com/js/js_array_methods.asp
          } else {
            //update the score and do something else
            this.score += 10;
            console.log(this.score);
          }
          asteroids.splice(j, 1); // removing the hitted asteroid
          this.lasers.splice(i, 1); // removing the laser beam that hitted the target to prevent hitting the newly created smaller asteroids
          break; // exiting the loop to be safe not checking already removed stuff
        }
      }
    }
  }
}

Ship.prototype.boost = function() {
  var boostForce = p5.Vector.fromAngle(this.heading);
  boostForce.mult(0.1);
  this.vel.add(boostForce);
}

Ship.prototype.render = function() {
  push();
  translate(this.pos.x, this.pos.y);
  rotate(this.heading + PI / 2);
  fill(0);
  if (this.boosting) {
    console.log("bosting");
    stroke(255, 0, 0);
    line(-this.r + 3, this.r + 3, this.r - 3, this.r + 3);
  }
  if (this.danger) {
    stroke(255, 0, 0);
  } else if (this.safe) {
    stroke(0, 255, 0);
  } else {
    stroke(255);
  }
  triangle(-this.r, this.r, this.r, this.r, 0, -this.r);
  pop();
}

Ship.prototype.edges = function() {
  if (this.pos.x > width + this.r) {
    this.pos.x = -this.r;
  } else if (this.pos.x < -this.r) {
    this.pos.x = width + this.r;
  }
  if (this.pos.y > height + this.r) {
    this.pos.y = -this.r;
  } else if (this.pos.y < -this.r) {
    this.pos.y = height + this.r;
  }
}

Ship.prototype.setRotation = function(angle) {
  this.rotation = angle;
}

Ship.prototype.turn = function(angle) {
  this.heading += this.rotation;
}

////// LASER

function Laser(spos, angle) {
  this.pos = createVector(spos.x, spos.y);
  this.vel = p5.Vector.fromAngle(angle);
  this.vel.mult(10);
  this.r = 1;
}

// collision detection for asteroids and other eventual additional stuff
Laser.prototype.hits = function(target) {
  var d = dist(this.pos.x, this.pos.y, target.pos.x, target.pos.y);
  if(d < this.r + target.r){
    //console.log("hit!");
    return true;
  } else {
    return false;
  }
}

Laser.prototype.update = function() {
  this.pos.add(this.vel);
}

Laser.prototype.render = function() {
  push();
  strokeWeight(2);
  stroke(255);
  point(this.pos.x, this.pos.y);
  pop();
}

Laser.prototype.offscreen = function() {
  if (this.pos.x > width + this.r || this.pos.x < -this.r || this.pos.y > height + this.r || this.pos.y < -this.r) {
    return true;
  } else {
    return false;
  }
}

///// ENERGY

function Energy(pos, vel) {
  this.pos = pos.copy();
  this.vel = vel.copy();
  this.vel.mult(-0.2);
  //this.vel.add(p5.Vector.random2D().mult(-0.5));
  this.r = 10;
  this.life = random(100, 300);
  this.alive = true;

this.update = function() {
    this.pos.add(this.vel);
    this.life -= 0.2;
  }

this.render = function() {
    if (this.life > 20) {
      noFill();
      stroke(0, this.life, 0);
      ellipse(this.pos.x, this.pos.y, this.r, this.r);
    }
  }
}

Energy.prototype.edges = function() {
  if (this.pos.x > width + this.r) {
    this.pos.x = -this.r;
  } else if (this.pos.x < -this.r) {
    this.pos.x = width + this.r;
  }
  if (this.pos.y > height + this.r) {
    this.pos.y = -this.r;
  } else if (this.pos.y < -this.r) {
    this.pos.y = height + this.r;
  }
}

function generateEnergy(pos, vel) {
    energy.push(new Energy(pos, vel));
}

///// DEBRIS

function Debris(pos, vel) {
  this.pos = pos.copy();
  this.vel = vel.copy();
  this.vel.add(p5.Vector.random2D().mult(random(0.5, 1.5)));
  this.transparency = random(200, 255);

this.update = function() {
    this.pos.add(this.vel);
    this.transparency -= 2;
  }

this.render = function() {
    if (this.transparency > 0) {
      stroke(this.transparency);
      point(this.pos.x, this.pos.y);
    }
  }
}

function generateDebris(pos, vel, n) {
  for (var i = 0; i < n; i++) {
    debris.push(new Debris(pos, vel));
  }
}

///// ASTEROIDS

Asteroid.prototype.explode = function() {
  //var debrisVel = p5.Vector.random2D().mult(random(0.5, 1.5));
  var debrisVel = this.vel.copy();
  var debrisNum = this.r * 5;
  generateDebris(this.pos, debrisVel, debrisNum); // handeling ship explosion
}

Asteroid.prototype.breakup = function() {
  var newA = [];
  if (this.sides > 5) {
    newA[0] = new Asteroid(this.pos, this.sides);
    newA[1] = new Asteroid(this.pos, this.sides);
  }
  return newA; // returning the array with my new asteroids
}

Asteroid.prototype.update = function() {
  this.pos.add(this.vel);
  this.angle += this.increment;
}

Asteroid.prototype.render = function() {
  push();
  translate(this.pos.x, this.pos.y);
  rotate(this.angle);
  noFill();
  stroke(255);
  //ellipse(0, 0, this.r*2, this.r*2);
  beginShape();
  for (var i = 0; i < this.sides; i++) {
    var angle = map(i, 0, this.sides, 0, TWO_PI);
    var r = this.r + this.offset[i];
    var x = r * cos(angle);
    var y = r * sin(angle);
    vertex(x, y);
  }
  endShape(CLOSE);
  pop();
}

Asteroid.prototype.edges = function() {
  if (this.pos.x > width + this.r) {
    this.pos.x = -this.r;
  } else if (this.pos.x < -this.r) {
    this.pos.x = width + this.r;
  }
  if (this.pos.y > height + this.r) {
    this.pos.y = -this.r;
  } else if (this.pos.y < -this.r) {
    this.pos.y = height + this.r;
  }
}

Asteroid.prototype.setRotation = function(angle) {
  this.rotation = angle;
}

Asteroid.prototype.turn = function(angle) {
  this.heading += this.rotation;
}

 
var ship;
var asteroids = [];
var astnum;
var initastnum = 2;
var debris = [];
var energy = [];
var gameLevel = 0;
var message;
​
function setup() {
  createCanvas(windowWidth, windowHeight);
  textFont("Courier");
  ship = new Ship();
  initialize("let's play!", initastnum);
}
​
function draw() {
  background(0);
  for (var i = debris.length - 1; i >= 0; i--) {
    debris[i].update();
    debris[i].render();
    if (debris[i].transparency <= 0) {
      debris.splice(i, 1);
    }
  }
​
  for (var i = energy.length - 1; i >= 0; i--) {
    energy[i].update();
    energy[i].render();
    energy[i].edges();
    if (ship.hit(energy[i]) && !ship.safe) {
      ship.safe = true;
      setTimeout(function() {
        ship.safe = !ship.safe;
      }, 2000);
      ship.getBonus();
      energy[i].alive = false;
    };
    if (energy[i].life <= 20) {
      energy[i].alive = false;
    };
    if (!energy[i].alive) {
      energy.splice(i, 1);
    };
  }
​
  if (ship.alive) {
    ship.update();
    ship.render();
    ship.edges();
  } else {
    console.log("Game Over");
    message = "Game Over";
    //restart();
  };
​
  if (asteroids.length == 0) { // player cleared the level
    astnum += 3;
    initialize("You Win! Level up!", astnum);
  }
​
  for (var i = asteroids.length - 1; i >= 0; i--) {
    asteroids[i].render();
    asteroids[i].update();
    asteroids[i].edges();
    if (ship.hit(asteroids[i]) && !ship.safe) {
      ship.danger = true;
      setTimeout(function() {
        ship.danger = !ship.danger;
      }, 100);
      ship.getDamage(asteroids[i]);
      console.log("Damaging the shield " + ship.shieldLevel);
      asteroids[i].explode();
      asteroids.splice(i, 1);
      //console.log(asteroids.length);
      //ship.explode();
    }
  }
​
  //interface info
  ship.interface();
  }
​
​
  function initialize(messageText, newastnum) {
    message = messageText;
    gameLevel += 1;
    astnum = newastnum;
    basicinit();
  }
​
  function restart(messageText, newastnum) {
    ship.init();
    gameLevel = 1;
    asteroids = [];
    energy = [];
    message = messageText;
    astnum = newastnum;
    basicinit();
  }
​
  function basicinit() {
    for (var i = 0; i < astnum; i++) {
      asteroids.push(new Asteroid());
    }
    ship.shieldLevel == 100;
    ship.safe = true;
    setTimeout(function() {
      ship.safe = false;
      message = "";
    }, 4000);
  }
​
​
  function keyReleased() {
    if (keyCode == RIGHT_ARROW || keyCode == LEFT_ARROW) {
      ship.setRotation(0);
    } else if (keyCode == UP_ARROW) {
      ship.boosting = false;
    }
  }
​
  function keyPressed() {
    if (key == ' ') {
      ship.lasers.push(new Laser(ship.pos, ship.heading));
    } else if (keyCode == RIGHT_ARROW) {
      ship.setRotation(0.1);
    } else if (keyCode == LEFT_ARROW) {
      ship.setRotation(-0.1);
    } else if (keyCode == UP_ARROW) {
      ship.boosting = true;
    } else if (keyCode == ENTER && message == "Game Over") {
      console.log("DAMN!!");
      restart("let's play again!", initastnum);
    }
  }
​
​
function windowResized() {
    resizeCanvas(windowWidth, windowHeight);
}
​
/////// SHIP Class
​
function Ship() {
  this.pos = createVector(width / 2, height / 2 + 50);
  this.vel = createVector(0, 0);
  this.r = 10;
  this.heading = 0;
  this.rotation = 0;
  this.boosting = false;
  this.lasers = [];
  this.shieldLevel = 100;
  this.shieldMax = 200;
  this.alive = true;
  this.danger = false;
  this.safe = true;
  this.score = 0;
}
​
Ship.prototype.interface = function() {
  textSize(14);
  fill(255);
  noStroke();
  text("Score = " + this.score, 50, 50);
  //text("Shield = " + constrain(round(ship.shieldLevel), 0, 100), 50, 65);
  if (this.shieldLevel >= this.shieldMax) {
    text("Shield = Max!", 50, 65);
  } else {
    text("Shield = " + constrain(round(this.shieldLevel), 0, round(this.shieldLevel)), 50, 65);
  }
  text("Level = " + gameLevel, 50, 80);
  if (message) {
    textSize(32);
    text(message, width / 2 - message.length * 10, height / 2);
  }
}
​
Ship.prototype.init = function() {
  this.pos = createVector(width / 2, height / 2 + 50);
  this.vel = createVector(0, 0);
  ship.alive = true;
  ship.score = 0;
  ship.shieldLevel = 100;
}
​
Ship.prototype.hit = function(obj) {
  var d = dist(this.pos.x, this.pos.y, obj.pos.x, obj.pos.y);
  if (d < this.r + obj.r) {
    return true;
  } else {
    return false;
  }
}
​
Ship.prototype.getDamage = function(obj) {
  var damount = obj.r; // the bigger the object hitting the ship the heavier the damage amount
  this.shieldLevel -= damount;
  if (this.shieldLevel <= 0) {
    this.explode();
  }
}
​
Ship.prototype.getBonus = function() {
  this.shieldLevel += 30;
  this.score += 20;
  this.shieldLevel = constrain(this.shieldLevel, 0, this.shieldMax);
}
​
Ship.prototype.explode = function() {
  var debrisVel = p5.Vector.random2D().mult(random(0.5, 1.5));
  //var debrisVel = p5.Vector.add(this.lasers[i].vel.mult(0.2), asteroids[j].vel);
  var debrisNum = 50;
  generateDebris(this.pos, debrisVel, debrisNum); // handeling ship explosion
  this.alive = false;
}
​
Ship.prototype.update = function() {
  this.pos.add(this.vel);
  this.vel.mult(0.99); // simulating friction
  this.turn();
  if (this.boosting) {
    this.boost();
  }
  for (var i = this.lasers.length - 1; i >= 0; i--) {
    this.lasers[i].render();
    this.lasers[i].update();
    //console.log(this.lasers.length);
    if (this.lasers[i].offscreen()) { // cleaning up my laser beam array when beams are out off the screen
      this.lasers.splice(i, 1);
      //console.log(this.lasers.length);
    } else {
      for (var j = asteroids.length - 1; j >= 0; j--) {
        if (this.lasers[i].hits(asteroids[j])) {
          console.log("asteroid number " + j + " has been hitted! " + asteroids.length);
          var debrisVel = p5.Vector.add(this.lasers[i].vel.mult(0.2), asteroids[j].vel);
          var debrisNum = (asteroids[j].r) * 5;
          generateDebris(asteroids[j].pos, debrisVel, debrisNum); // handeling asteroids explosions
          var newAsteroids = asteroids[j].breakup(); // returns an array of two smaller asteroids
          if (newAsteroids.length > 0) {
            //console.log(newAsteroids);
            //asteroids.push(newAsteroids[0]); //asteroids.push(newAsteroids[1]);
            var probability = random() * 100;
            if (probability > 80) {
              //console.log("Shupershield!!!!");
              generateEnergy(asteroids[j].pos, debrisVel);
            }
            asteroids = asteroids.concat(newAsteroids); // concatenating (merging) arrays // https://www.w3schools.com/js/js_array_methods.asp
          } else {
            //update the score and do something else
            this.score += 10;
            console.log(this.score);
          }
          asteroids.splice(j, 1); // removing the hitted asteroid
          this.lasers.splice(i, 1); // removing the laser beam that hitted the target to prevent hitting the newly created smaller asteroids
          break; // exiting the loop to be safe not checking already removed stuff
        }
      }
    }
  }
}
​
Ship.prototype.boost = function() {
  var boostForce = p5.Vector.fromAngle(this.heading);
  boostForce.mult(0.1);
  this.vel.add(boostForce);
}
​
Ship.prototype.render = function() {
  push();
  translate(this.pos.x, this.pos.y);
  rotate(this.heading + PI / 2);
  fill(0);
  if (this.boosting) {
    console.log("bosting");
    stroke(255, 0, 0);
    line(-this.r + 3, this.r + 3, this.r - 3, this.r + 3);
  }
  if (this.danger) {
    stroke(255, 0, 0);
  } else if (this.safe) {
    stroke(0, 255, 0);
  } else {
    stroke(255);
  }
  triangle(-this.r, this.r, this.r, this.r, 0, -this.r);
  pop();
}
​
Ship.prototype.edges = function() {
  if (this.pos.x > width + this.r) {
    this.pos.x = -this.r;
  } else if (this.pos.x < -this.r) {
    this.pos.x = width + this.r;
  }
  if (this.pos.y > height + this.r) {
    this.pos.y = -this.r;
  } else if (this.pos.y < -this.r) {
    this.pos.y = height + this.r;
  }
}
​
Ship.prototype.setRotation = function(angle) {
  this.rotation = angle;
}
​
Ship.prototype.turn = function(angle) {
  this.heading += this.rotation;
}
​
​
////// LASER
​
function Laser(spos, angle) {
  this.pos = createVector(spos.x, spos.y);
  this.vel = p5.Vector.fromAngle(angle);
  this.vel.mult(10);
  this.r = 1;
}
​
// collision detection for asteroids and other eventual additional stuff
Laser.prototype.hits = function(target) {
  var d = dist(this.pos.x, this.pos.y, target.pos.x, target.pos.y);
  if(d < this.r + target.r){
    //console.log("hit!");
    return true;
  } else {
    return false;
  }
}
​
Laser.prototype.update = function() {
  this.pos.add(this.vel);
}
​
Laser.prototype.render = function() {
  push();
  strokeWeight(2);
  stroke(255);
  point(this.pos.x, this.pos.y);
  pop();
}
​
Laser.prototype.offscreen = function() {
  if (this.pos.x > width + this.r || this.pos.x < -this.r || this.pos.y > height + this.r || this.pos.y < -this.r) {
    return true;
  } else {
    return false;
  }
}
​
​
///// ENERGY
​
function Energy(pos, vel) {
  this.pos = pos.copy();
  this.vel = vel.copy();
  this.vel.mult(-0.2);
  //this.vel.add(p5.Vector.random2D().mult(-0.5));
  this.r = 10;
  this.life = random(100, 300);
  this.alive = true;
​
  this.update = function() {
    this.pos.add(this.vel);
    this.life -= 0.2;
  }
​
  this.render = function() {
    if (this.life > 20) {
      noFill();
      stroke(0, this.life, 0);
      ellipse(this.pos.x, this.pos.y, this.r, this.r);
    }
  }
}
​
Energy.prototype.edges = function() {
  if (this.pos.x > width + this.r) {
    this.pos.x = -this.r;
  } else if (this.pos.x < -this.r) {
    this.pos.x = width + this.r;
  }
  if (this.pos.y > height + this.r) {
    this.pos.y = -this.r;
  } else if (this.pos.y < -this.r) {
    this.pos.y = height + this.r;
  }
}
​
function generateEnergy(pos, vel) {
    energy.push(new Energy(pos, vel));
}
​
​
///// DEBRIS
​
function Debris(pos, vel) {
  this.pos = pos.copy();
  this.vel = vel.copy();
  this.vel.add(p5.Vector.random2D().mult(random(0.5, 1.5)));
  this.transparency = random(200, 255);
​
  this.update = function() {
    this.pos.add(this.vel);
    this.transparency -= 2;
  }
​
  this.render = function() {
    if (this.transparency > 0) {
      stroke(this.transparency);
      point(this.pos.x, this.pos.y);
    }
  }
}
​
​
function generateDebris(pos, vel, n) {
  for (var i = 0; i < n; i++) {
    debris.push(new Debris(pos, vel));
  }
}
​
​
///// ASTEROIDS 
​
function Asteroid(pos, s) {
  if (pos) {
    this.pos = pos.copy();
  } else {
    this.pos = createVector(random(width), random(height));
  }
  this.vel = p5.Vector.random2D();
  this.sides = floor(random(15, 30));
  if (s) {
    this.sides = floor(s * 0.5);
  } else {
    this.sides = floor(random(15, 30));
  }
  this.rmin = 20;
  this.rmax = 40;
  this.r = map(this.sides, 15, 30, this.rmin, this.rmax);
  this.offset = [];
  for (var i = 0; i < this.sides; i++) {
    this.offset[i] = random(-5, 5); // alternative // -this.r/8, this.r/8
  }
  this.angle = 0;
  var increment = map(this.r, this.rmin, this.rmax, 0.1, 0.01);
  if (random() > 0.5) {
    this.increment = increment * -1;
  } else {
    this.increment = increment;
  }
}
​
Asteroid.prototype.explode = function() {
  //var debrisVel = p5.Vector.random2D().mult(random(0.5, 1.5));
  var debrisVel = this.vel.copy();
  var debrisNum = this.r * 5;
  generateDebris(this.pos, debrisVel, debrisNum); // handeling ship explosion
}
​
Asteroid.prototype.breakup = function() {
  var newA = [];
  if (this.sides > 5) {
    newA[0] = new Asteroid(this.pos, this.sides);
    newA[1] = new Asteroid(this.pos, this.sides);
  }
  return newA; // returning the array with my new asteroids
}
​
Asteroid.prototype.update = function() {
  this.pos.add(this.vel);
  this.angle += this.increment;
}
​
Asteroid.prototype.render = function() {
  push();
  translate(this.pos.x, this.pos.y);
  rotate(this.angle);
  noFill();
  stroke(255);
  //ellipse(0, 0, this.r*2, this.r*2);
  beginShape();
  for (var i = 0; i < this.sides; i++) {
    var angle = map(i, 0, this.sides, 0, TWO_PI);
    var r = this.r + this.offset[i];
    var x = r * cos(angle);
    var y = r * sin(angle);
    vertex(x, y);
  }
  endShape(CLOSE);
  pop();
}
​
Asteroid.prototype.edges = function() {
  if (this.pos.x > width + this.r) {
    this.pos.x = -this.r;
  } else if (this.pos.x < -this.r) {
    this.pos.x = width + this.r;
  }
  if (this.pos.y > height + this.r) {
    this.pos.y = -this.r;
  } else if (this.pos.y < -this.r) {
    this.pos.y = height + this.r;
  }
}
​
Asteroid.prototype.setRotation = function(angle) {
  this.rotation = angle;
}
​
Asteroid.prototype.turn = function(angle) {
  this.heading += this.rotation;
}
​

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