jennyzha – project 07

sketch

// Jenny Zhang
// Section D
// jennyzha@andrew.cmu.edu
// Project 07 

//http://mathworld.wolfram.com/Epitrochoid.html

function setup() {
  createCanvas(480, 480);
}

function draw() {
  background(255, 200, 200);
  translate(width/2, height/2);  // moving the drawing to center 

  drawEpitrochoid();
}

function drawEpitrochoid() {

    var n = 1500;          
    noFill();
    stroke(255);

    var x;
    var y;
    var h = constrain(mouseX, 0, 480); //distance between radius of smaller circle to the curve drawn (contrained and varied between left and right borders)
    var a = 300;    //radius of bigger circle
    var b = a/constrain(mouseY, 0, 480);  //radius of smaller circle (constrained to the left and right borders)


    beginShape();
        for (var i=0; i < n; i++) {

            var t = map(i, 0, n, 0, TWO_PI);

            var x = (a + b) * cos(t) - h * cos (((a+ b)/b)*t); //epitrochoid equation
            var y = (a + b) * sin(t) - h * sin (((a+ b)/b)*t); //epitrochoid equation
           
            vertex(x, y);
        }  
    endShape();
}

I really enjoyed playing around with all of the possible varying numbers in this project and am very pleased with the outcome. Moving your mouse very slowly throughout the canvas you’re able to see so many different beautiful designs made by the epitrochoid curves.