import processing.video.*;

MovieMaker mm;
color[][] clre;
PVector[][] posizioni;

PVector origin;
ArrayList particles = new ArrayList();
int numParticles = 10000;
int z = 0; 

void setup()
{
  size(400, 400);
  colorMode(HSB, 360, 100, 100, 100);
  PFont font = loadFont("Standard0757-8.vlw");
  textFont(font, 32); 
  clre = new color[width][height/2];
  posizioni = new PVector[width][height/2];
  //mm = new MovieMaker(this, width, height, "drawing.mov", 30, MovieMaker.VIDEO, MovieMaker.LOSSLESS);
}

void draw()
{
  background(1, 0, 100);
  
  textAlign(CENTER);
  fill(1, 100, 100, 1);

  text("Hello World."+'\n'+"We are Pixels." , width/2, 50);
  

 for(int i=0; i<width; i++) {
    for(int j = 0; j<height/2; j++) {
       clre[i][j] = get(i,j);
       if(clre[i][j] != -1){
            if(z < numParticles){
            posizioni[i][j] = new PVector(i,j,0);  
            origin = new PVector(posizioni[i][j].x, 130+posizioni[i][j].y, 0);
            PVector a = new PVector();
            PVector v = new PVector();        
            PVector l = new PVector(random(width), random(height) , 0);
            particles.add(new Particle(a,v,l, origin, random(0.05f, 2.0f)));
            z++;
            }
      }
    }
  }
          for (int h = 0; h<particles.size()-1; h++){
            Particle prt = (Particle) particles.get(h);
            prt.run();
            
            PVector actualVel = prt.getVelocity(); 
            PVector attrito = PVector.mult(actualVel,-0.05); 
            prt.add_force(attrito);
            
            if(keyPressed) { 
               if (key == 'a' || key == 'A')
              { 
                PVector origLoc = prt.getOrigin();
                PVector diff = PVector.sub(origLoc,prt.getLocation()); 
                diff.normalize(); 
                float factor = 0.5f;  
                diff.mult(factor); 
                prt.setAcceleration(diff); 
              }
               if (key == ' ' || key == ' ')
              { 
               mm.finish();
              }                  
            } 
            if(mousePressed) {  
              PVector mouseLoc = new PVector(mouseX, mouseY, 0);
              PVector diff = PVector.sub(mouseLoc,prt.getLocation()); 
              diff.normalize(); 
              float factor = 1.0f;  
              diff.mult(factor); 
              prt.setAcceleration(diff); 
              
            } 
          }
          //mm.addFrame();
}

  class Particle {
  PVector or;
  PVector loc;
  PVector vel;
  PVector acc;
  float ms;
  float distance;

  Particle(PVector a, PVector v, PVector l, PVector o, float ms_) {
    acc = a;
    vel = v;
    loc = l;
    ms = ms_;
    or = o;
  }

  void run() {
    update();
    render();
  }

  void update() {
    vel.add(acc);
    loc.add(vel);
    acc = new PVector();
  }
 
  void render() {
    stroke(1, 100, 0);
    point(loc.x,loc.y);
  }
 
 void add_force(PVector force) { 
    force.div(ms);
    vel.add(force);
  }  
 
 float getMass() { 
    return ms; 
  }  
  
  PVector getLocation() {
    return loc;
  }
  PVector getOrigin() {
    return or;
  }
  PVector getVelocity() {
    return vel;
  }
  void setLocation(PVector l){
    loc = l;    
  }

  void setAcceleration(PVector a){
    acc = a;
  }
}