Project 07: Composition with Curves

//Christy Zo
//Section C

var nPoints = 400;
function setup() {
    createCanvas(480, 480);
}

function draw() {
    background(220);
    push();
    translate(width / 2, height / 2);
    drawEpitrochoidCurve();
    pop();
    push();
    translate(width / 2, height / 2);
    drawEpicycloidCurve();
    pop();
    push();
    translate(width / 2, height / 2);
    rotate(radians(90)); //rotating Epicycloid to create a radial pattern
    drawEpicycloidCurve();
    pop();
    push();
    translate(width / 2, height / 2);
    rotate(radians(45));
    drawEpicycloidCurve();
    pop();
    push();
    translate(width / 2, height / 2);
    rotate(radians(135));
    drawEpicycloidCurve();
    pop();


}

function drawEpicycloidCurve() {
    // Epicycloid:
    // http://mathworld.wolfram.com/Epicycloid.html
    
    var x;
    var y;
    
    var a = constrain(mouseY,0, height);
    var b = constrain(mouseX, 0, width);
    //var h = constrain(mouseY / 8.0, 0, b);
    //var ph = mouseX / 50.0;
    noFill();
    stroke(0);
    beginShape();
    for (var i = 0; i < nPoints; i++) {
        var t = map(i, 0, nPoints, 0, TWO_PI);
        
        x = 4 * b * cos (t)* cos (t)* cos (t);
        y = a * sin (t) *sin (t)* sin (t);
        
      vertex(x, y);
    }
    endShape(CLOSE);

}

function drawEpitrochoidCurve() {
    // Epicycloid:
    // http://mathworld.wolfram.com/Epitrochoid.html
    
    var x;
    var y;
    
    var a = mouseX;
    var b = a / 2.0;
    var h = constrain(mouseY / 8.0, 0, b);
    var ph = mouseX / 120.0;
    
    fill(mouseX, mouseY, mouseX);
    beginShape();
    for (var i = 0; i < nPoints; i++) {
        var t = map(i, 0, nPoints, 0, TWO_PI);
        
        x = (a + b) * cos(t) - h * cos(ph + t * (a + b) / b);
        y = (a + b) * sin(t) - h * sin(ph + t * (a + b) / b);
        vertex(x, y);
    }
    endShape(CLOSE);
    
}