This is an entity that can be drawn also.
An Entity is an unimportant base class for anything that should have an update method.
This is the base class for any non-empty scene, any real game scene.
Represents a loaded Image.
A Scene is an object that has a state and is a master to many other object.
This mixin gives you a method to write the current FPS into the title bar.
A mixin you can use if you need a sync
method to keep within a certain fps.