//setPosition

//setPenTipPosition

//moveTo

let drawerImage, drawerSound

p5.prototype.initDrawer = function(image='holding.png', sound='short_pencil_stroke.mp3'){

  drawerSound = this.loadSound(sound)

  drawerImage = this.loadImage(image)

}

p5.prototype.registerMethod('init', p5.prototype.initDrawer);

​

function Drawer(p) {

  this.sketch = p || window; 

​

  this.setSpeed = function(speed) {

    this.speed = speed

  }

​

  this.sound = drawerSound

  this.setSound = function(p5AudioObject) {

    this.sound = p5AudioObject

  }

​

  this.speed = 2;

  this.canSaveSteps = false

​

  this.steps = []

  this.saveSteps = function() {

    this.canSaveSteps = true

  }

  this.stopSaveSteps = function() {

    this.canSaveSteps = false

    this.steps = []

  }

​

  this.image = drawerImage;

  this.setImage = function(p5ImageObject) {

    this.image = p5ImageObject

  }

​

  this.position = this.sketch.createVector(this.sketch.width/2,this.sketch.height/2) ;

  this.setPosition = function(vector) {

    this.position = vector

  }

​

  this.targetPosition = undefined;

  this.setTargetPosition = function(vector) {

    this.targetPosition = vector

  }

​

  this.moveTo = function(vector, replaceSpeed = this.speed) {

    this.setTargetPosition(vector)

    this.startMovement(replaceSpeed)

  }

​

  this.getTargetDistance = function() {

    return this.sketch.dist(this.targetPosition.x, this.targetPosition.y, this.position.x, this.position.y);

  }

​

  this.hasToMove = function() {

    return this.targetPosition && this.position && this.getTargetDistance() > 0

  }

​

  this.startMovement = function(replaceSpeed) {

    if (this.hasToMove())

      this.updateToNextPosition(replaceSpeed)

    this.draw()

    this.playAudio()

  }

  this.playAudio = function(){

    if(this.hasToMove() && !this.sound.isPlaying())

    this.sound.loop();

    else

    this.sound.stop();

  }

​

  this.penTipPosition = this.sketch.createVector(-52, -128)

  this.setPenTipPosition = function(vector) {

    this.penTipPosition = createVector(-vector.x,-vector.y)

  }

​

  this.draw = function() {

    this.sketch.push()

    this.sketch.translate(this.penTipPosition)

​

    //draw an image as last element to override everythin an maitain the shadow effect

    this.sketch.image(this.image, this.position.x, this.position.y)

    this.sketch.pop()

  }

​

  this.updateToNextPosition = function(replaceSpeed) {

    //show image as last element

    let nextY, nextX, distanceFromX, distanceFromY, minimalDistanceFromX, minimalDistanceFromY

​

    let definedSpeed = replaceSpeed ? replaceSpeed : this.speed

​

​

    //absolute distance (ignore minus)

    distanceFromX = this.sketch.abs(this.targetPosition.x - this.position.x)

    distanceFromY = this.sketch.abs(this.targetPosition.y - this.position.y)

​

    //max step available based on distance and speed 

    minimalDistanceFromX = this.sketch.min(definedSpeed, distanceFromX)

    minimalDistanceFromY = this.sketch.min(definedSpeed, distanceFromY)

​

​

    //current x is bigger

    if (this.position.x > this.targetPosition.x)

      nextX = this.position.x - minimalDistanceFromX

    else

      nextX = this.position.x + minimalDistanceFromX

​

    //current y is bigger

    if (this.position.y > this.targetPosition.y)

      nextY = this.position.y - minimalDistanceFromY

    else

      nextY = this.position.y + minimalDistanceFromY

​

    let nextPositionVector = this.sketch.createVector(nextX, nextY)

​

    if (this.canSaveSteps)

      this.steps.push(nextPositionVector)

​

    //update the current position

    this.setPosition(nextPositionVector)

  }

}