String Art

var dx1;
var dy1;
var dx2;
var dy2;

var numLines = 50;

function setup() {
    createCanvas(400, 400);
    background(220);
}

function draw() {
    background(200);
    //line(mouseX, mouseX, 150-mouseY, 300+mouseY);
    //line(mouseX, mouseX, 350-mouseY, 100+mouseY);

    var x1 = mouseX;
    var y1 = mouseX;
    var x2 = mouseX;
    var y2 = mouseX;

    dx1 = (mouseX-mouseY)/numLines;
    dy1 = (mouseX-mouseY)/numLines;
    dx2 = (150-mouseY-350-mouseY)/numLines;
    dy2 = (300+mouseY-100+mouseY)/numLines;

    for (var i = 0; i <= numLines; i += 1) {
        stroke(0);
        line(x1, y1, x2, y2);
        x1 += dx1;
        y1 += dy1;
        x2 += dx2;
        y2 += dy2;
    }

    var r = 20;

    fill(255,140,140);
    noStroke();
    circle(mouseY, mouseX, 2*r);

    fill(140,140,255);
    circle(width-mouseY, height-mouseX, 40);

    var xc1 = mouseY;
    var yc1 = mouseX+r;
    var xc2 = width-mouseY;
    var yc2 = height-mouseX-r;


    for (var i = 0; i <= 2*PI; i += PI/4) {
        stroke(0);
        line(xc1, yc1, xc2, yc2);
        if (i <= PI/2) {
            xc1 += r*Math.sin(i);
            yc1 -= r-r*Math.cos(i);
            xc2 -= r*Math.sin(i);
            yc2 += r-r*Math.cos(i);
        } else if (i > PI/2 & i <= PI) {
            xc1 -= r*Math.sin(i);
            yc1 -= r-r*Math.cos(i);
            xc2 += r*Math.sin(i);
            yc2 += r-r*Math.cos(i);
        } else if (i > PI & i <= 3*PI/2) {
            xc1 -= r*Math.sin(i);
            yc1 += r-r*Math.cos(i);
            xc2 += r*Math.sin(i);
            yc2 -= r-r*Math.cos(i);
        } else if (i > 3*PI/2 & i <= 2*PI) {
            xc1 += r*Math.sin(i);
            yc1 += r-r*Math.cos(i);
            xc2 -= r*Math.sin(i);
            yc2 -= r-r*Math.cos(i);
        }
    }
}