agusman-Project11-TurtleGraphicsFreestyle

sketch

//Anna Gusman
//agusman@andrew.cmu.edu
//Section E
//Turtle Graphics


function turtleLeft(d) {
    this.angle -= d;
}


function turtleRight(d) {
    this.angle += d;
}


function turtleForward(p) {
    var rad = radians(this.angle);
    var newx = this.x + cos(rad) * p;
    var newy = this.y + sin(rad) * p;
    this.goto(newx, newy);
}


function turtleBack(p) {
    this.forward(-p);
}


function turtlePenDown() {
    this.penIsDown = true;
}


function turtlePenUp() {
    this.penIsDown = false;
}


function turtleGoTo(x, y) {
    if (this.penIsDown) {
      stroke(this.color);
      strokeWeight(this.weight);
      line(this.x, this.y, x, y);
    }
    this.x = x;
    this.y = y;
}


function turtleDistTo(x, y) {
    return sqrt(sq(this.x - x) + sq(this.y - y));
}


function turtleAngleTo(x, y) {
    var absAngle = degrees(atan2(y - this.y, x - this.x));
    var angle = ((absAngle - this.angle) + 360) % 360.0;
    return angle;
}


function turtleTurnToward(x, y, d) {
    var angle = this.angleTo(x, y);
    if (angle < 180) {
        this.angle += d;
    } else {
        this.angle -= d;
    }
}


function turtleSetColor(c) {
    this.color = c;
}


function turtleSetWeight(w) {
    this.weight = w;
}


function turtleFace(angle) {
    this.angle = angle;
}


function makeTurtle(tx, ty) {
    var turtle = {x: tx, y: ty,
                  angle: 0.0,
                  penIsDown: true,
                  color: color(128),
                  weight: 1,
                  left: turtleLeft, right: turtleRight,
                  forward: turtleForward, back: turtleBack,
                  penDown: turtlePenDown, penUp: turtlePenUp,
                  goto: turtleGoTo, angleto: turtleAngleTo,
                  turnToward: turtleTurnToward,
                  distanceTo: turtleDistTo, angleTo: turtleAngleTo,
                  setColor: turtleSetColor, setWeight: turtleSetWeight,
                  face: turtleFace};
    return turtle;
}

var t1;

function setup() {
    createCanvas(400,400);
    background(0);
    t1 = makeTurtle(200, 200);
    t1.setColor(255);
    t1.setWeight(1);
    t1.penDown();

    var sideLength = 20;
    for(var i = 0; i < 100; i++) {
        t1.penDown();
        sideLength = sideLength - 20;
        t1.right(2);
        makeSquare(sideLength);

    }
  }

function makeSquare(sideLength)
    {t1.forward(sideLength);
    t1.right(90);
    t1.forward(sideLength);
    t1.right(90);
    t1.forward(sideLength);
    t1.right(90);
    t1.forward(sideLength);
    t1.right(90);

    ellipse(t1.x,t1.y,10,10)
    t1.penUp();
    t1.right(90);
    t1.forward(sideLength)
    t1.right(90);
    t1.forward(sideLength)

    ellipse(t1.x,t1.y,10,10)
}

Inspired by my struggles with the lab this week, I wanted to dive a bit further into the mechanism of iterated rotation. Here’s a simple transformation I thought looked really lovely.