class Particle
{
 Particle(float _x, float _y, float _r, int _h)
 {
  x = _x;  
  y = _y;
  
  dt = 0.04;
  vx = 0;
  vy = 0;
  
  or = _r;
  r = _r;
  
  if(h != 0)
  {
    colorMode(HSB, 255);  
    c = color(h + random(30), 200 + random(55), 50 + random(205), 4);
    colorMode(RGB, 255);
  }
  else
  {
    c = color(random(255), random(255), random(255), 4);
  }
 }
 
 void Interact(float _x, float _y)
 {
   ax = _x - x;
   ay = _y - y;
   vx += ax * dt;
   vy += ay * dt;
   if(sqrt(vx*vx + vy*vy) > 5*r)
   {
     vx *= 0.1;
     vy *= 0.1;
   }
   x += vx * dt;
   y += vy * dt;
   vx *= 0.9;
   vy *= 0.9;
   
   if(x < 0) x = width - 1;
   if(y < 0) y = height - 1;
   if(x > width) x = 0;
   if(y > height) y = 0;
   
   r = or + 0.25*or*cos(millis() * 0.0001);
 }
 
 void Render()
 {
   fill(c);
   pushMatrix();
     translate(x, y, 0); 
     rotateZ(PI*0.5 + atan2(vy, vx));         
     beginShape(TRIANGLES);
       vertex(0, -r, 0);
       vertex(-r, r, 0);
       vertex(r, r, 0);
     endShape();
   popMatrix();
 } 
 
 int c;
 float or, r; 
 float x, y;
 float vx, vy, ax, ay;
 float dt;
}