Graphing 2D Equations
Graphics the following equation: sin(n cos(r) + 5θ) where n is a function of horizontal mouse location. Original by Daniel Shiffman
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function setup() {
createCanvas(710, 400);
pixelDensity(1);
}
function draw() {
loadPixels();
let n = (mouseX * 10.0) / width;
const w = 16.0; // 2D space width
const h = 16.0; // 2D space height
const dx = w / width; // Increment x this amount per pixel
const dy = h / height; // Increment y this amount per pixel
let x = -w / 2; // Start x at -1 * width / 2
let y;
let r;
let theta;
let val;
let bw; //variable to store grayscale
let i;
let j;
let cols = width;
let rows = height;
for (i = 0; i < cols; i += 1) {
y = -h / 2;
for (j = 0; j < rows; j += 1) {
r = sqrt(x * x + y * y); // Convert cartesian to polar
theta = atan2(y, x); // Convert cartesian to polar
// Compute 2D polar coordinate function
val = sin(n * cos(r) + 5 * theta); // Results in a value between -1 and 1
//var val = cos(r); // Another simple function
//var val = sin(theta); // Another simple function
bw = color(((val + 1) * 255) / 2);
index = 4 * (i + j * width);
pixels[index] = red(bw);
pixels[index + 1] = green(bw);
pixels[index + 2] = blue(bw);
pixels[index + 3] = alpha(bw);
y += dy;
}
x += dx;
}
updatePixels();
}
