Basic implementations of colour metaballs and meta-diamonds

Basic_metaballs.pde

//Reference
//Coding Train: https://youtu.be/ccYLb7cLB1I
//https://github.com/CodingTrain/website/tree/main/CodingChallenges/CC_028_MetaBalls/Processing/CC_028_MetaBalls
//https://www.gamedev.net/articles/programming/graphics/exploring-metaballs-and-isosurfaces-in-2d-r2556/

Blob[] blobs = new Blob[20];
float min=1;

void setup() {
  size(720, 360);
  colorMode(HSB);
  for (int i = 0; i < blobs.length; i++) {
    blobs[i] = new Blob(random(width), random(height), i);
  }
}
void draw() {
  clear();
  loadPixels();
  for (int x = 0; x < width; x++) {
    for (int y = 0; y < height; y++) {
      float hue, saturation, brightness;

      float sum = 0;
      for (Blob b : blobs) {
        if (b.order > blobs.length/4) {
          sum += b.r*b.r / ((x-b.pos.x)*(x-b.pos.x) + (y-b.pos.y)*(y-b.pos.y));//metaball
        } else {
          sum += b.r / (2*abs(x-b.pos.x) + 2*abs(y-b.pos.y));//Meta-Diamond
        }
      }

      hue = constrain(sum*255, 10, 50);//blue-cyan cores constrain(sum*255, 100, 150);
      saturation = constrain(sum*255, 100, 255);
      if (min*2 > sum)  continue;
      else brightness = sum*69;

      int index = x + y * width;
      pixels[index] = color(hue, saturation, brightness);
    }
  }

  updatePixels();
  for (Blob b : blobs) {
    b.update();
    //b.show();
  }
}

class Blob {
  PVector pos;
  float r;
  PVector vel;
  int order;

  Blob(float x, float y, int number) {
    this.order = number;
    this.pos = new PVector(x, y);
    this.vel = PVector.random2D();
    this.vel.mult(random(1, 3));
    this.r = random(40, 7);
  }

  void update() {
    this.pos.add(vel); 
    if (this.pos.x > width || this.pos.x < 0) {
      this.vel.x *= -1;
    }
    if (this.pos.y > height || this.pos.y < 0) {
      this.vel.y *= -1;
    }
  }

  void show() {
    noFill();
    stroke(200);
    circle(this.pos.x, this.pos.y, this.r*2);
  }
}