void updateCamera() {
    if (KeyInput.isKeyDown(Keyboard.KEY_UP   )) pushCamera(-1,  1) ;
    if (KeyInput.isKeyDown(Keyboard.KEY_DOWN )) pushCamera( 1, -1) ;
    if (KeyInput.isKeyDown(Keyboard.KEY_RIGHT)) pushCamera( 1,  1) ;
    if (KeyInput.isKeyDown(Keyboard.KEY_LEFT )) pushCamera(-1, -1) ;
    //if (KeyInput.isKeyDown(Keyboard.KEY_SPACE)) zoomHome() ;
    if (lockTarget != null) followLock() ;
  }