class Particle
{
  float posX, posY; // position variables
  int posXround, posYround; // rounded position variables
  float speedX, speedY; // speed variables
  float scaleFactor = 1;
  float inSpeed = s5p*1.0;  // initial speed variable
  float ffb = 0; 
  float ffFactor = 10;  // determines moment when a freefall should take place
  boolean ff = false;

  float grav = 9.8;  // gravity constant
  float fricWall = 5;  // friction constant

  // reading from image
  float s1,s2,s3,s4,s5,s6,s7,s8,s9;
  int vX, vY;  // surface curvature vectors (based on brightness)
  float satP = 0;

  Particle (float x, float y, float fW) {
    posX = x;
    posY = y;
    posXround = int(posX);
    posYround = int(posY);
    speedX = 0;
    speedY = 2;
    // fricWall = fW;
  }

  void update(){

    // PARTICLE POSITION

    if (posX > 107 && posX < 493)
    {
      posX += speedX*s6p*(s5p*2);
      posXround = int(posX);
    }
    else if (posX < 102)
    {
      posX = 108;
      posXround = int(posX);
    }
    else 
    {
      posX = 489;
      posXround = int(posX);
    }

    if (posY > 107 && posY <= 490)
    {
      posY += speedY*(s5p*2);
      posYround = int(posY);
    }
    else if (posYround >= 490)
    {
      posY = 108;
      speedY = inSpeed;
      posYround = int(posY);
      posX = random(106,494);
      posXround = int(posX);
      ff = false;
    }

    fill(60,100,100,30);
    rect(posXround, posYround, 5, 5);
    //println(diffY);

    fill(60,100,0,20);

    // definition speedX

    if ((posYround-105)*390+(posXround-105) < 152100) {
      satP = (100.0-sS[(posYround-105)*390+(posXround-105)])/100.0;
      vX = sVx[(posYround-105)*390+(posXround-105)];  // vector force x direction
      speedX = (vX/2)*satP;  // x speed update
      // define speedY
      vY = sVy[(posYround-105)*390+(posXround-105)];  // vector force y direction
      if ( ((-vY/2) + (grav-fricWall)) * satP > 0) {
        speedY = (((-vY/2) + (grav-fricWall)))*satP;  // y speed update
      } 
      else { 
        speedY = .25;
      }

    }
    else {
      satP = 0;
      vX = vX;
      vY = vY;
    }



    /*
    // definition speed freefall
     if (ff == true)
     {
     if (s5 >= ffb)
     {
     ff = true;
     fill(0,100,0,90);
     }
     else{
     ff = false;
     }
     if(ff)
     {
     speedY = grav;
     
     
     // println("freefall!");
     }
     if(!ff)
     {
     speedY = grav-fW;
     if (s5 >=ffb)
     {
     ff = true;
     }
     }
     }
     if (ff == false)
     {
     speedY = grav-fW;
     // println("not freefalling");
     if (diffY > ffFactor)
     {
     //  println("diffY > ffFactor");
     ff = true;
     ffb = s5;
     }
     }
     // println("diffY= " + diffY + "  s5 = " + s5 + "  ffb = " + ffb);
     */
  }
}