Nina Yoo – Project 07 – Curves

sketch
I was really intrigued by the hypotrochoid curve and how it was drawn the site itself. Through this project I was able to play around with the functions of cos and sin which I havent been able to delve into before. It was interesting to play with the numbers and see what different shapes appeared because of the repetitively drawn lines.

/* Nina Yoo
Section E
nyoo@andrew.cmu.edu
Project-07 Composition with Curves*/

var nPoints = 200
function setup() {
    createCanvas(480, 480);
    		frameRate(15);

    
}

function draw() {
	background(200,34,164);
	push();
	//into middle
	translate(width/2, height/2);
	drawHypotrochoidCurve();
	pop();
}



function drawHypotrochoidCurve(){
		//Hyptotrochoid
		//Link: http://mathworld.wolfram.com/Hypotrochoid.html

		var x;
		var y;
		
		var h = 15;
	

		var a = map(mouseX, 0,width,100,300); // (wat u want to effect, orginal range, new range) makes the variables interactive
		var b = map(mouseY, 0, height, 100,300);

		stroke(210,36,117);
		strokeWeight(2);

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

				// set variable t within the for loop so it keeps on looping (this acts as the angle for mouse)
				var t = map (i, 0, nPoints, 0 , 330 );

					// equation for the curve
				x = (a - b) * cos(t) + h * cos((a - b) * t); 
				y = (a - b) * sin(t) - h * sin((a - b) * t);
				vertex(x,y); // setting the patternn in the middle

			}
		endShape(CLOSE);






}