PVector.js

static class myPVector
{
    float x, y, t_x, t_y;

    myPVector(float xx,float yy)
    {  
	x = xx;
	y = yy;
    }
    
    void add(myPVector v)
    {
	y+=v.y;
	x+=v.x;
    }

    void sub(myPVector v)
    {
	y-=v.y;
	x-=v.x;
    }
    void mult(float n)
    {
	x*=n;
	y*=n;
    }
    void div(float n)
    {
	x/=n;
	y/=n;
    }

    
    void normalize()
    {
	float m=mag();
	if(m!=0) div(m);
    }
    
    float mag()
    {
	return sqrt(x*x+y*y);
    }
    
    void limit(float max)
    {
	if(mag() > max)
	{
	    normalize();
	    mult(max);
	}
    }

        // static
    static myPVector add(myPVector v, myPVector v1)
    {
	myPVector v2 = new myPVector(v.x + v1.x, v.y + v1.y);
	return v2;
    }
    
    static myPVector sub(myPVector v, myPVector v1)
    {
	myPVector v2 = new myPVector(v.x - v1.x, v.y - v1.y);
	return v2;
    }
    
    static myPVector mult(myPVector v, float n)
    {
  myPVector v1 = new myPVector(v.x*=n, v.y*=n);
  return v1;
    }

    static myPVector div(myPVector v, float n)
    {
  myPVector v1 =  new myPVector(v.x/=n, v.y/=n);
  return v1;
    }
    //static

}

class Mover
{

    myPVector location;
    myPVector velocity;
    myPVector acceleration;
    float topspeed;
    int color_a, color_b, color_c, translate;    
    Mover()
    {
	location = new myPVector(random(width), random(height));
	acceleration = new myPVector(0, 0);
	velocity = new myPVector(0,0);
	topspeed = 4;
	color_a = (int)random(0, 255);
	color_b = (int)random(0, 255);
	color_c = (int)random(0, 255);
	translate = (int)random(0, 100);
    }
    
    void update()
    {
	velocity.add(acceleration);
	velocity.limit(topspeed);
	location.add(velocity);
	acceleration.mult(0);	
    }
    
    void myApplyForce(myPVector force)
    {
	acceleration.add(force);
    }
    
    void checkEdge()
    {
	if(location.x>width) acceleration.x=0;
 	else if(location.x<0) location.x=width;

	if(location.y>height) location.y=0;
	else if(location.y<0) location.y=height;
    }
    
    void display()
    {
	stroke(0);
	fill(color_a, color_b, color_c, translate);
	ellipse(location.x,location.y,16,16);
    }

}

Mover mover;
myPVector wind;
float t;
void setup()
{
    background(225);
    size(200,200);
    smooth();
    mover = new Mover();
    wind = new myPVector(0, 0.02);
    t = 100;
}

 

void draw()
{
    t += 0.01;
    wind.normalize();
    wind.mult(-1*map(noise(t), 0, 1, 0, 0.01));
    mover.myApplyForce(wind);
    if(mover.location.y < 0)
    {
	myPVector fo = new myPVector(-0.1, 0);
	mover.myApplyForce(fo);
    }
    mover.update();
    //mover.checkEdge();
    mover.display();
}