void camera()
{
  translate(width/2, height/2, -30);
  if(!stopped)
  {
    if(mousePressed)
    {
      scl += (mouseY - pmouseY) / 3.0;
    }
    else
    {
      newXmag = mouseX/float(width) * TWO_PI;
      newYmag = mouseY/float(height) * TWO_PI;
      float diff = xmag-newXmag;
      if (abs(diff) >  0.01) { xmag -= diff/4.0; }

      diff = ymag-newYmag;
      if (abs(diff) >  0.01) { ymag -= diff/4.0; }
    }
  }
  rotateX(-ymag/4.2+PI/1.8); 
  rotateZ(-xmag-PI/3.0);
  scale(scl);
}

boolean changeTheme(String name, int it)
{
  if(it > theme.length)
    return false;
  if(theme[it] == null)
  {
    name = themeList[0];
  }
  if(name == "next")
  {
    int l = themeList.length;
    for(int i=0; i < l; ++i)
    {
        if(theme[it].getname() == themeList[i])
        {
          i++;
          if(i >= l)
          {
            i = 0;
            name = "none";
          }
          else
            name = themeList[i];
          break;
        }
    }
  }
  boolean success = false;
  for(int i = 0; i < num; ++i)
    windows[i].stopglow(it);
  
  if(name == "themeOne")
  {
     theme[it] = new themeOne(themecolors[it],it);
     theme[it].start(themespeed[it]);
     success = true;
  }
  else if(name == "themeRandom")
  {
     theme[it] = new themeRandom(themecolors[it], it, num / 18);
     theme[it].start(themespeed[it]);
     success = true;
  }
  else if(name == "themeH1")
  {
     theme[it] = new themeH1(themecolors[it], it);
     theme[it].start(themespeed[it]);
     success = true;
  }
  else if(name == "themeH5")
  {
     theme[it] = new themeH5(themecolors[it], it);
     theme[it].start(themespeed[it]);
     success = true;
  }
  else if(name == "themeV1")
  {
     theme[it] = new themeV1(themecolors[it], it);
     theme[it].start(themespeed[it]);
     success = true;
  }
  else if(name == "themeV5")
  {
     theme[it] = new themeV5(themecolors[it], it);
     theme[it].start(themespeed[it]);
     success = true;
  }
  else if(name == "none")
  {
    theme[it] = null;
    success = true;
  }

  return success;
}
int getnb(int i, int dir, boolean flipv)
{
  int totlen = 2*(w+l);
  int row = i / totlen;
  int spl = i % totlen;
  dir %= 4;
  if(dir == 0)
  {
    spl--;
    if(spl < 0)
      spl = totlen - 1;
  }
  else if(dir == 1)
  {
    row++;
    if(row >= h)
    {
      if(!flipv)
        return -1;
      row = 0;
    }
  }
  else if(dir == 2)
  {
    spl++;
    if(spl >= totlen)
      spl = 0;
  }
  else if(dir == 3)
  {
    row--;
    if(row < 0)
    {
      if(!flipv)
        return -1;
      row = h-1;
    }
  }
  return row*totlen + spl;
}

int getleft(int i)
{
  return getnb(i, 0, false);
}

int getup(int i)
{
  return getnb(i, 1, false);
}

int getright(int i)
{
  return getnb(i, 2, false);
}

int getdown(int i)
{
  return getnb(i, 3, false);
}

boolean createWindows()
{
  num = (l+w)*2*h;
  println("Anzahl Fenster: "+num);
  if(num > 10000)
  {
    println("Mehr als 10000 Fenster. Programm wird beendet");
    return false;
  }
  windows = new Window[num];
  int totlen = 2*(w+l);
  float x = -l*sizexy/2, y = -w*sizexy/2;
  float s[] = {sizexy, sizez};
  for(int i = 0; i < num; ++i)
  {
    int row = i / totlen;
    int spl = i % totlen;
    float dx, dy;
    if(spl < l) 
    {
      dx = sizexy;
      dy = 0.0;
      s[0] = sizexy;
    }
    else if(spl >= l+w && spl < 2*l+w)
    {
      dx = -sizexy;
      dy = 0.0; 
      s[0] = -sizexy;
    }
    else if(spl >= l && spl < l+w)
    {
      dx = 0.0;
      dy = sizexy;
      s[0] = sizexy;
    }
    else
    {
      dx = 0.0;
      dy = -sizexy;
      s[0] = -sizexy;
    }
    
    float p[] = {x,y,row*sizez-sizez*h/2};
    int gs = int(float(row) / float(h) * 128) + (i%2 * 10);
    windows[i] = new Window(s, p, dx == 0.0, color(gs + 64, gs + 64, gs + 100));
    x += dx;
    y += dy;
  }
  
  for(int i = 0; i < 3; ++i)
  {
     if(theme[i] != null)
      theme[i].start(themespeed[i]); 
  }
  return true;
}