Moving the clouds

Our next enhancement will be to make clouds, which are just sitting in the air and move to the left. The idea here is to simulate some kind of wind property in the game world, while each cloud will also move at slightly different speeds to make their movement look more natural. In addition to this, there needs to be a condition to let more clouds appear at the right end of the level. Otherwise, the game will run out of clouds at some point. We could just take the easy route here and spawn a huge number, say 1000 clouds, but this is not very clever performance-wise, and this also does not tackle our original problem, that is, the game will run out of clouds at some point. So, a better approach to solve our problem is to keep the maximum number of existing cloud objects to a minimum.

Make the following changes to the Clouds class:

private Cloud spawnCloud () {
  Cloud cloud = new Cloud();
cloud.dimension.set(dimension);
  // select random cloud image
cloud.setRegion(regClouds...