Snowy Mountain

ArrayList<Snow> snows = new ArrayList<Snow>();

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void setup() {

  size(640, 640);

  noStroke();

}

​

void draw() {

  background(255);

  snows.add(new Snow());

  snows.add(new Snow());

​

  for (int i = 0; i < snows.size (); i++) {

    Snow s = snows.get(i);

    /* Formular for landscape */

    float boundary = 200-abs(sin(radians(s.loc.x)))*cos(radians(s.loc.x/2))*100;

    s.display(boundary);

  }

}

class Snow {

  PVector loc, acc, vel, gravity;

  float r, mass;

  float alpha = 200;

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  Snow() {

    r = random(2, 20);

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    loc = new PVector(random(-200, width+200), -r);

    vel = new PVector();

    acc = new PVector();

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    mass = 50/r;

  }

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  void applyForce(PVector force) {

    acc.add(PVector.div(force, mass));

  }

​

  void display(float boundary) {

    vel.add(acc);

    loc.add(vel);

    acc.mult(0);

    if (loc.y > height-boundary) {

      vel.y *= 0.9;

      vel.x = 0;

      fill(255, 150, 150, alpha);

      alpha--;

      if (alpha > 0) {

        ellipse(loc.x, loc.y, r, r);

      } else {

        snows.remove(this);

      }

    } else {

      gravity = new PVector(map(mouseX, 0, width, -0.03, 0.03), map(mouseY, 0, height, 0.01, 0.1));

      fill(255, 150, 150);

      ellipse(loc.x, loc.y, r, r);

      applyForce(gravity);

    }

  }

}

​

​

​