For this assignment I began with the equation for the Quadratrix of Hippias, and scaled the equation based on the Y-Coordinate of the mouse. I also identified the limits of the formula and changed their visibility based on the X-Coordinate of the mouse.
sketchDownload
var t = 0;
var points = 200;
var eX = [];
var eY = [];
var a = 0;
var b = 0;
var r = 200;
function setup() {
createCanvas(480, 480);
background(0);
stroke(255);
strokeWeight(1);
noFill();
a = 15;
b = mouseY;
}
function draw() {
background(0);
if (mouseY < 150 || mouseY > 330) {
a = map(mouseY,0,height,-40,40);
} else {a = 15}
for (let i = 0; i < height; i += 1) {
eY[i] = i;
eX[i] = eY[i]*((1)/(tan((PI*eY[i])/(2*a))));
line(eX[i]+240,eY[i]+240,eX[i+1]+240,eY[i+1]+240);
line(eX[i]+240,-eY[i]+240,eX[i+1]+240,-eY[i+1]+240);
if (abs((eX[i])-(eX[i+1])) > 400) {
push();
strokeWeight(2);
stroke(map(mouseX,0,width,0,255),0,0);
line(eX[i]+240,eY[i]+240,eX[i+1]+240,eY[i+1]+240);
line(eX[i]+240,-eY[i]+240,eX[i+1]+240,-eY[i+1]+240)
pop();
}
}
}