public class Boule {

  float x;
  float y;
  float []X;
  float []Y;
  float startx;
  float starty;
  float vitx0;
  float vity0;
  float vitx;
  float vity;
  float angle;
  float coeff;
  int couleur;
  int index;

  Boule() {

    couleur= color(random(255), random(255), random(255));
    startx=random(400, 600);
    starty=random(400, 600);
    vitx0=4-random(4);
    vity0=4-random( 4);
    coeff=random(1, 15);
    X=new float[0];
    Y=new float[0];
    x=startx;
    y=starty;
    vitx=vitx0;
    vity=vity0;
  }
}

import controlP5.*;


ControlP5 cp;
PGraphics feuille;
Boule []boulesArray;
int [][]XX;
int [][]YY;
int nbeBoules;
Button btnFond;
Textfield nbeCyclesInfo;
color fillCol;
color backColor=0;
PApplet app=this;
int count;
float minx;
float miny;
float maxx;
float maxy;
int nbeCycles;
PFont font;

public void setup() {
  size(800, 800, P2D);
  smooth();
  cp=new ControlP5(this);
  background(backColor);
  font = loadFont("Arial-BoldMT-14.vlw"); 
  textFont(font);  
  textAlign(CENTER);  
  frameRate(600);
  btnFond=cp.addButton("Background", 10, 10, 10, 60, 20);
  btnFond.setColorBackground(255-backColor);
  if(backColor==0){
  btnFond.setCaptionLabel("  White");
  }else{
    btnFond.setCaptionLabel("  Black");
  }
  btnFond.setColorCaptionLabel(color(backColor));
  count=0;
  nbeCycles=(int)random(300, 3000);
  nbeCyclesInfo=cp.addTextfield(str(nbeCycles)+" cycles", 10, 50, 30, 20);
  nbeCyclesInfo.setValue(str(count));
  minx=600;
  miny=600;
  maxx=400;
  maxy=400;
  nbeBoules=(int) random(2, 6);
  boulesArray= new Boule[nbeBoules];	
  XX=new int [nbeBoules][nbeCycles+1];
  YY=new int [nbeBoules][nbeCycles+1];
  for (int i=0;i<nbeBoules;i++) {		
    boulesArray[i]=new Boule();
  }
  fillCol=color(random(255), random(255), random(255));
  fill(fillCol, 20);
  noStroke();
  pre();
  count=0;
}
void draw() {

  pushMatrix();
  float ech=(float)width/max((maxy-miny), (maxx-minx));
  scale(ech);
  if (maxy-miny<maxx-minx) {
    translate(-minx, -(maxy+miny+minx-maxx)/2);
  }
  else {
    translate(-(maxx+minx+miny-maxy)/2, -miny);
  }
  count++;

  if (count<nbeCycles) {
    nbeCyclesInfo.setValue(str(count+1));
    for (int i=0;i<nbeBoules;i++) {  
      //    fill(boulesArray[i].couleur,30); 
      //    noStroke();
      //    ellipse(XX[i][count], YY[i][count], 4, 4); 
      stroke(boulesArray[i].couleur, 45);
      if (i<nbeBoules-1) {
        //line(boulesArray[i].X[count], boulesArray[i].Y[count], boulesArray[i+1].X[count], boulesArray[i+1].Y[count]);
        line(XX[i][count], YY[i][count], XX[i+1][count], YY[i+1][count]);
      }
      else {
        //line(boulesArray[i].X[count], boulesArray[i].Y[count], boulesArray[0].X[count], boulesArray[0].Y[count]);
        line(XX[i][count], YY[i][count], XX[0][count], YY[0][count]);
      }
    }
  }
  popMatrix();
  if (count==nbeCycles+300) {
    println(frameRate);
    setup();
  }
  cp.draw();
}
void pre() 

{	

  while (count<nbeCycles) {
    count++;
    for (int i=0;i<nbeBoules;i++) {               

      if (i<nbeBoules-1) {
        boulesArray[i].angle= atan2(boulesArray[i].y-boulesArray[i+1].y, boulesArray[i].x-boulesArray[i+1].x)-atan2(boulesArray[i].vity, boulesArray[i].vitx);
      }//
      else {
        boulesArray[i].angle=atan2(boulesArray[i].y-boulesArray[0].y, boulesArray[i].x-boulesArray[0].x)-atan2(boulesArray[i].vity, boulesArray[i].vitx);
      }
      if (abs(boulesArray[i].angle)>PI) {
        boulesArray[i].angle=-boulesArray[i].angle;
      }
      boulesArray[i].angle=-boulesArray[i].angle/boulesArray[i].coeff;
      float vitxinstant=boulesArray[i].vitx;
      float vityinstant=boulesArray[i].vity;

      boulesArray[i].vitx=vitxinstant*cos(boulesArray[i].angle)-vityinstant*sin(boulesArray[i].angle);//+((mouseX-boulesArray[i].x)/100);
      boulesArray[i].vity=vityinstant*cos(boulesArray[i].angle)+vitxinstant*sin(boulesArray[i].angle);//+((mouseY-boulesArray[i].y)/100);
      boulesArray[i].x+=boulesArray[i].vitx;
      boulesArray[i].y+=boulesArray[i].vity;
      maxx=max(maxx, boulesArray[i].x);
      maxy=max(maxy, boulesArray[i].y);
      minx=min(minx, boulesArray[i].x);
      miny=min(miny, boulesArray[i].y);
      boulesArray[i].X=append(boulesArray[i].X, boulesArray[i].x);
      boulesArray[i].Y=append(boulesArray[i].Y, boulesArray[i].y);

      XX[i][count]=floor(boulesArray[i].x);
      YY[i][count]=floor(boulesArray[i].y);
    }
  }
}

void mousePressed() {
  if (mouseButton==LEFT) {   
    setup();
  }
}
void Background(int value) {
  btnFond.setColorBackground(backColor);
  backColor=abs(255-backColor);
  btnFond.setColorCaptionLabel(color(backColor));  
  background(backColor);
  if(backColor==0){
  btnFond.setCaptionLabel("  White");
  }else{
    btnFond.setCaptionLabel("  Black");
  }
}