* continous). Press space to accelerate the simulation and backspace to 

 * decimate/erase the most recent shape.

 * Squiggle speed sets the speed of the points, Simplify time sets the speed that 

 * erasing goes at. 

 */

​

// size of the canvas

let canvasWidth = 400;

let canvasHeight = 400;

​

function setup() 

{

  createCanvas(canvasWidth, canvasHeight);

}

​

​

let mouseHeld = false; //is the mouse held down?

​

let squiggles = [];

let squiggleSpeed = 0.2; // must be less than 1

​

let simplifyTimer = 0;

let simplifyTime = 0.5;

​

let start = true;

​

function draw() 

{

  background(0);

  stroke(255);

  deltaTime = deltaTime / 100; // for some reason its in milliseconds? so i just made it to seconds lol

  if (keyIsDown(32))

  {

    deltaTime *= 10; // accelerate time itself! with a click of the button!

  }

  //line(0, 0, mouseX, mouseY)

  //line(canvasWidth, 0, mouseX, mouseY)

  //line(0, canvasHeight, mouseX, mouseY)

  //line(canvasWidth, canvasHeight, mouseX, mouseY)

  //draw points

  if (mouseIsPressed)

  {

    if (!mouseHeld)

    {

      mouseHeld = true;

      squiggles.push(new squiggle());

    }

    squiggles[squiggles.length - 1].points.push(new point(mouseX, mouseY));

  }

  else

  { 

    mouseHeld = false;

  }

  if (simplifyTimer < simplifyTime)

    simplifyTimer += deltaTime;

  if (keyIsDown(BACKSPACE))

  {

   if (squiggles.length > 0 && simplifyTimer >= simplifyTime){

      simplifyTimer = 0;

      squiggles[squiggles.length - 1] = simplifyLine(squiggles[squiggles.length - 1])

    } 

  }

  //display and move each point

  for (let i = 0; i < squiggles.length; i ++)

  {

    if (squiggles[i].points.length == 0)

      squiggles.splice(i, 1)

    else

    {

      for (let j = 0; j < squiggles[i].points.length - 1; j ++)

      {

        //squiggles[i].points[j].x += squiggleSpeed * deltaTime;

        //squiggles[i].points[j].y += squiggleSpeed * deltaTime;

​

        let rise = squiggles[i].points[j + 1].y - squiggles[i].points[j].y;

        let run = squiggles[i].points[j + 1].x - squiggles[i].points[j].x;

​

        squiggles[i].points[j].x += run * deltaTime * squiggleSpeed;

        squiggles[i].points[j].y += rise * deltaTime * squiggleSpeed;

​

        if (squiggles[i].points[j].x > canvasWidth ||

            squiggles[i].points[j].x < 0 ||

            squiggles[i].points[j].y > canvasHeight ||

            squiggles[i].points[j].y < 0)

        {

          squiggles[i].points.splice(j, 1)

        }

        else

        {

          line(squiggles[i].points[j].x, squiggles[i].points[j].y, canvasWidth / 2, canvasHeight / 2);

        }

      }

​

      if (squiggles[i].points.length > 1)

      {

        let last = squiggles[i].points.length - 1;

​

        let rise = squiggles[i].points[last].y - squiggles[i].points[0].y;

        let run = squiggles[i].points[last].x - squiggles[i].points[0].x;

​

        let distance = sqrt(pow(rise, 2) + pow(run, 2))

​

        if (distance == 0)

          distance = 0.0001

​

        squiggles[i].points[last].x += -run * deltaTime * squiggleSpeed * 10 / distance;

​

        squiggles[i].points[last].y += -rise * deltaTime * squiggleSpeed * 10 / distance;

​

        if (squiggles[i].points[last].x > canvasWidth ||

            squiggles[i].points[last].x < 0 ||

            squiggles[i].points[last].y > canvasHeight ||

            squiggles[i].points[last].y < 0)

        {

          squiggles[i].points.pop();

        }

      } 

    }

  }  

}

​

function simplifyLine(simplifiedLine)

{  

  for (let i = 0; i < simplifiedLine.points.length; i ++)

    {

      if (i%2 == 0)

      {

        simplifiedLine.points.splice(i, 1);

      }

    }

  return simplifiedLine;

}

​

class squiggle

{

  constructor()

  {

    this.points = [];

  }

}

​

class point

{

  constructor(xInput, yInput)

  {

    this.x = xInput;

    this.y = yInput;

  }

}