/*involuto()
  creates an involuted flow. this objects is randomly trailing, 
  it controls by a mouse position
*/

class involuto{
  float x,y; //base position
  float xp,yp; //position [called by pointer]
  float radmo,themo; //controlled by mouse position
  
  float thtv; //theta velocity
  
  int tm; //timecount
  int tmv=int(random(5,25)); //velocity
  
  float thtm; //time-based theta
  
  involuto(){
    //no constructors here
  }
  
  void trail(){
    xp=mouseX+sin(pt.xp);
    yp=mouseY+sin(pt.yp);
    
    radmo=sqrt(sq(250-xp)+sq(250-yp));
    themo=atan2(250-xp,250-yp)*(180/PI);
    
    thtv=random(-10,10);
    themo+=thtv;
    thtv*=random(0.995,1.005);
    
    tm+=tmv*0.1;
    thtm=tmv*sin(tm);
    
    x=xp+radmo*cos(PI/180*(themo+thtm));
    y=yp+radmo*sin(PI/180*(themo+thtm));
    
    for(int a=0;a<tmv;a++){
      stroke(0,0,0,32);
      point(x-(x-xp)*sin(a),y-(y-yp)*sin(a));
    }
  }
}

  /*pointer()
  this simple class is have unique use, with calling it.
*/

class pointer{
  float xp;
  float yp;
  
  pointer(){
    //no constructors here
  }
  
  void trail(float xp0,float yp0){
    xp=xp0;
    yp=yp0;
  }
}

  /*point involute
  
  created with processing 0135
  by rce12
  9 march 2008
  
  - move your mouse to draw it
  - click your mouse for freeze that
  - wait a second(s) for quarter-clear screen
  
  simple and unique. using a simple class for make it cool than
  set position manually. squashy yellow background, black painting
  and funky interaction make it isn't insane.
*/

int tfade=0;

involuto[] it;
int nmb=100;

pointer pt=new pointer();

boolean startnow=true;

void setup(){
  size(500,500);
  background(240,222,58);
  
  it=new involuto[nmb];
  
  for(int a=0;a<it.length;a++){
    it[a]=new involuto();
  }
}

void draw(){
  if(startnow){
    if(tfade++>100){
      fill(240,222,58,50);
      rect(0,0,width,height);
      
      tfade=0;
    }
  
    pt.trail(0.0f,0.0f);
  
    for(int a=0;a<nmb;a++){
      it[a].trail();
    }
  }
}

void mousePressed(){
  startnow=!startnow;
}