The day-to-night effect really helps add a sense of passage of time. The day-to-night cycle is one in which, as the player plays your game, the environment changes depending on the time of day. The first part of developing this feature is to have some internal reference point for the time of day built into the game because in most games, the passage of time is independent of the real world time. The second part of this feature is to add some additional lightmaps that make the world feel as if it is occurring at a specific time of day, such as a dark lightmap with light sources we learned in the previous section, which gives the player the illusion of night.
The following class diagram (Figure 10) describes the class that we will implement for the first part of this feature:
Figure 10
The ClockActor class derives from Label so that we get the benefits of using a Label object in a Stage. We only need one ClockActor object and this object will live in the...