com­p­e­n­d­i­u­m 1

• Show Sketch

/** @peep sketchcode */
 
int NUM_CIRCLES = 100;
float MIN_RADIUS = 20;
float MAX_RADIUS = 50;
 
float DELTA_ANGLE = TWO_PI/36;
 
Circle[] circles;
 
void setup() {
  size(300, 300);
  frameRate(10);
  background(255);
  smooth();
  circles = new Circle[NUM_CIRCLES];
  for (int i = 0; i < circles.length; i++) {
    circles[i] = new Circle(random(width), random(height), random(MIN_RADIUS, MAX_RADIUS));
  }
}
 
void update() {
  for (int i = 0; i < circles.length; i++) {
    circles[i].update();
  }
}
 
void draw() {
  update(); // Update all of the circles
  strokeWeight(1);
  for (int i = 0; i < circles.length; i++) {
    // Get a first circle
    Circle circle1 = circles[i];
    for (int j = i+1; j < circles.length; j++) {
      // Get a second circle
      Circle circle2 = circles[j];
      // If the circles are touching
      if (circle1.touching(circle2)) {
        // Calculate the grey value using the map function based on the distance between the circles
        stroke(map(circle1.distance(circle2), 0, circle1.radius + circle2.radius, 0, 255));
        // Draw a line between the centres of the circles
        line(circle1.x, circle1.y, circle2.x, circle2.y);
      }
    }
  }
}
 
class Circle {
  float x;
  float y;
  float radius;
 
  float heading;
  float speed;
 
  Circle(float _x, float _y, float _radius) {
    x = _x;
    y = _y;
    radius = _radius;
    heading = random(TWO_PI);
    speed = 1;
  }
 
  void draw() {
    pushStyle();
    noFill();
    stroke(0);
    strokeWeight(3);
    ellipseMode(RADIUS);
    pushMatrix();
    translate(x, y);
    rotate(heading);
    ellipse(0, 0, radius, radius);
    line(0, 0, radius, 0);
    popMatrix();
    stroke(192, 0, 0, 64);
    for (int i = 0; i < circles.length; i++) {
      Circle other = circles[i];
      if (touching(other)) {
        line(x, y, other.x, other.y);
      }
    }
    popStyle();
  }
 
  void update() {
    behaviour1();
    behaviour2();
    behaviour3();
    behaviour4();
  }
 
  void behaviour1() {
    // Constant linear motion
    float dx = speed * cos(heading);
    float dy = speed * sin(heading);
    x += dx;
    y += dy;
  }
 
  void behaviour2() {
    // Constrain to surface
    if (x < radius) x = radius;
    if (y < radius) y = radius;
    if (x > width - radius) x = width - radius;
    if (y > height - radius) y = height - radius;
  }
 
  void behaviour3() {
    // While touching another, change direction
    for (int i = 0; i < circles.length; i++) {
      if (circles[i] != this) {
        if (touching(circles[i])) {
          heading += random(-DELTA_ANGLE, DELTA_ANGLE);
        }
      }
    }
  }
 
  void behaviour4() {
    // While touching another, move away from its centre
    for (int i = 0; i < circles; i++) {
      if (circles[i] != this) {
        if (touching(circles[i])) {
          Circle other = circles[i];
          float d = distance(other);
 
          float dx = (other.x - x)/d;
          float dy = (other.y - y)/d;
          x -= speed * dx;
          y -= speed * dy;
        }
      }
    }
  }
 
  void touching(Circle other) {
    return (distance(other) < radius + other.radius);
  }
 
  float distance(Circle other) {
    return dist(x, y, other.x, other.y);
  }
}