Processing — Projects

Project 1: Point Scatter (Zay Legend)

What It Does

7,500 gold points wander randomly across a 300x300 canvas. Each point moves in a small random direction each frame and wraps around to the opposite edge when it goes out of bounds. The text "Zay Legend" is drawn in the center of the canvas.

How It Works

• Arrays store the x, y, and RGB color values for each of the 7,500 points
• setup() initializes all points at random positions and sets their color to gold (255, 215, 0)
• draw() moves each point by a random offset between -1 and 1 on both axes
• Edge wrapping: if a point goes past any edge, it reappears on the opposite side
• frameRate(1000) runs as fast as possible, creating a fast particle effect

Code

int count = 7500;

float[] x = new float[count];
float[] y = new float[count];
float[] r = new float[count];
float[] g = new float[count];
float[] b = new float[count];

void setup() {
  size(300, 300);
  for (int i = 0; i < count; i++) {
    x[i] = random(width);
    y[i] = random(height);
    r[i] = 255;
    g[i] = 215;
    b[i] = 0;
  }
  background(200);
  noSmooth();
  frameRate(1000);
}

void draw() {
  for (int i = 0; i < count; i++) {
    x[i] += random(-1, 1);
    y[i] += random(-1, 1);
    if (x[i] < 0) x[i] = width;
    if (x[i] > width) x[i] = 0;
    if (y[i] < 0) y[i] = height;
    if (y[i] > height) y[i] = 0;
    stroke(r[i], g[i], b[i]);
    point(x[i], y[i]);
    text("Zay Legend", 100, 100, 100);
  }
}

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Project 2: Interactive Spirograph

What It Does

Draws a spirograph pattern that updates in real time based on mouse position. Moving the mouse changes the shape of the pattern by controlling the inner radius (r2) and point distance (h). Keyboard controls let you adjust drawing speed and pause the animation.

Controls: - Mouse X/Y: Change spirograph shape (inner radius and point distance) - Keys 1–9: Change drawing speed (1 = slowest, 9 = fastest) - Spacebar: Pause/unpause

How It Works

• The outer radius r1 grows continuously, resetting to 0 when it exceeds half the canvas width
• Mouse X and Y are divided by 2 to produce r2 and h, respectively
• A SpiroCircle class encapsulates the hypotrochoid math and handles drawing
• drawIterations() steps through 1,000 angle increments per frame, drawing a point at each
• Stroke color uses sin(PI * i / iter) * 255 — a sine-wave grayscale gradient across the curve
• strokeWeight(6) makes each point visible and slightly overlapping for a smooth curve

Code

SpiroCircle sc;
float r1, incr;
boolean pause;

void setup() {
  size(400, 400);
  strokeWeight(25);
  smooth();
  sc = new SpiroCircle();
  r1 = 0.0;
  incr = 0.05;
  pause = false;
}

void draw() {
  r1 += incr;
  if (r1 > width / 2) r1 = 0.0;

  if (keyPressed) {
    if (key >= '1' && key <= '9')
      incr = ((int) key - '1' + 1) / 20.0;
    pause = (key == ' ');
  }

  if (!pause) {
    background(0);
    float mx = (mouseX == 0) ? 300 : mouseX;
    float my = (mouseY == 0) ? 300 : mouseY;
    sc.init(width/2, height/2, r1, mx/2, my/2);
    sc.drawIterations(1000, incr);
  }
}

class SpiroCircle {
  int cx, cy;
  float r1, r2, h;
  float prev_x, prev_y;
  boolean first;

  public void init(int x, int y, float radius_1, float radius_2, float point_distance) {
    cx = x; cy = y;
    r1 = radius_1; r2 = radius_2; h = point_distance;
    first = true;
  }

  public void drawIterations(int iter, float incr) {
    float rads = 0.0;
    for (int i = 0; i < iter; ++i) {
      stroke(sin(PI * i / iter) * 255 - 5);
      drawPoint(rads);
      rads += incr;
    }
  }

  private void drawPoint(float rads) {
    float x = cx + (r1 - r2) * cos(rads) + h * cos((r1 - r2) / r2 * rads);
    float y = cy + (r1 - r2) * sin(rads) + h * sin((r1 - r2) / r2 * rads);
    if (!first) { strokeWeight(6); point(x, y); }
    first = false;
    prev_x = x; prev_y = y;
  }
}

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Project 3: Gold Spirograph (Mouse-Controlled)

What It Does

Identical structure to Project 2 but renders the spirograph in solid gold (RGB 255, 215, 0) rather than a sine-wave grayscale gradient. The canvas is wider (1000x500) to give the pattern more room to expand.

How It Works

The core logic is the same as Project 2 — hypotrochoid equation, mouse-driven r2 and h, growing r1. The key difference is in drawIterations():

Project 2 (sine gradient):

stroke(sin(PI * i / iter) * 255 - 5);

Project 3 (solid gold):

stroke(255, 215, 0);

This small change produces a completely different visual character — a glowing, uniform gold curve instead of a shifting light-to-dark pattern.

Code

SpiroCircle sc;
float r1, incr;
boolean pause;

void setup() {
  size(1000, 500);
  strokeWeight(25);
  smooth();
  sc = new SpiroCircle();
  r1 = 0.0;
  incr = 0.05;
  pause = false;
}

void draw() {
  r1 += incr;
  if (r1 > width / 2) r1 = 0.0;

  if (keyPressed) {
    if (key >= '1' && key <= '9')
      incr = ((int) key - '1' + 1) / 20.0;
    pause = (key == ' ');
  }

  if (!pause) {
    background(0);
    float mx = (mouseX == 0) ? 300 : mouseX;
    float my = (mouseY == 0) ? 300 : mouseY;
    sc.init(width/2, height/2, r1, mx/2, my/2);
    sc.drawIterations(1000, incr);
  }
}

class SpiroCircle {
  int cx, cy;
  float r1, r2, h;
  float prev_x, prev_y;
  boolean first;

  public void init(int x, int y, float radius_1, float radius_2, float point_distance) {
    cx = x; cy = y;
    r1 = radius_1; r2 = radius_2; h = point_distance;
    first = true;
  }

  public void drawIterations(int iter, float incr) {
    float rads = 0.0;
    for (int i = 0; i < iter; ++i) {
      stroke(255, 215, 0);  // solid gold
      drawPoint(rads);
      rads += incr;
    }
  }

  private void drawPoint(float rads) {
    float x = cx + (r1 - r2) * cos(rads) + h * cos((r1 - r2) / r2 * rads);
    float y = cy + (r1 - r2) * sin(rads) + h * sin((r1 - r2) / r2 * rads);
    if (!first) { strokeWeight(6); point(x, y); }
    first = false;
    prev_x = x; prev_y = y;
  }
}

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Comparison: Projects 2 vs. 3

Feature	Project 2	Project 3
Canvas size	400x400	1000x500
Stroke color	Sine-wave grayscale gradient	Solid gold (255, 215, 0)
Mouse control	Yes	Yes
Speed keys (1–9)	Yes	Yes
Spacebar pause	Yes	Yes
Core math	Hypotrochoid	Hypotrochoid (identical)