constructor(x, y, xSpeed, ySpeed,photonColour,trail,trailColour,trailRes) {

    this.position = createVector(x, y)

    this.velocity = createVector(xSpeed,ySpeed)

    this.velocity.setMag(c)

    this.mass = 0.5

    //0.39269943999

    this.draw = 0

    this.photonColour = photonColour

    this.trail = trail

    this.trailColour = trailColour

    this.trailRes = trailRes

    this.history = []

  }

​

  show() {

    if (this.draw == 0 && this.position.x > 0 && this.position.x < width && this.position.y > 0 && this.position.y < height) {

    strokeWeight(2)

    stroke(this.photonColour)

    point(this.position.x, this.position.y)

    }

    if (((this.trail == 'On') || (this.trail == 'After' && this.draw == 2))) { 

    strokeWeight(1)

    stroke(this.trailColour,75)

    noFill()

    beginShape()

    for (let i = 0; i < this.history.length - 1; i += 2) {

      vertex(this.history[i].x,this.history[i].y)

    }

    endShape()

    }

  }

  update() {

    if (this.draw == 0) {

    if (frameCount % 2 == 0 && this.position.x > -15 && this.position.x < width + 15 && this.position.y > -15 && this.position.y < height + 15) {

    this.history.push(this.position.copy())

    }

    let dV = this.velocity.copy()

    dV.mult(dt)

    this.position.add(dV)

  }

  }

}