Mud Designer's world clock

Tonight I was able to finally get a world clock built in to the Mud Designer engine. The world clock is pretty flexible, allowing users to specify how many real-world hours pass before 1 in-game day is completed. The engine then does a break down and broadcasts updates every in-game minute.

Time of day states

If you set your in-game to real-world hour ratio to 4:24, then the update event will get called every 10 seconds. This means that 1 in-game minute will pass every 10 seconds. If the ratio is to low, the engine will switch over and broadcast updates every in-game hour instead, to prevent stress on the server.

The engine uses an ITimeOfDayState implementation to determine what the current time of day is. It holds a collection of these objects and transitions between the different times of day as needed. The ITimeOfDayState objects have a StartTime property that tells the engine when it needs to transition to the state. This allows users to create their own time of days, such as Evening and LateNight, and let the engine handle moving between the states.

Building a time of day state is really simple. You can just inherit from it's parent class like this:

public class AfternoonState : TimeOfDayState
{
    public AfternoonState()
    {
        this.StateStartTime = new TimeOfDay();
        this.StateStartTime.Hour = 12;
    }

    public override string Name { get { return "Afternoon"; } }

    public override TimeOfDay StateStartTime { get; set; }

You can of course choose to implement a state from ITimeOfDayState, but by inheriting from the abstract TimeOfDayState class, the time of day engine clock will be managed for you, along with the in-game to real-world time conversions.

The engine's IWorld implementation is notified every in-game minute that goes by (or hour if the frequency is to low). When the world is notified, it updates itself accordingly, and checks to see if the state needs to be changed. If so, it transitions the states and posts it's own event that notifies registered objects that a state change took place. This allows developers to publish messages to the users when the time of day changes.

The Engine Timer

Since the engine is being built with full cross-platform support via Portable Class Libraries, I ran in to an issue with the .NET built-in thread-safe Timer class missing. After doing some searching around, it seems that Microsoft did include it in their Portable Class Library profile, but Xamarin has not. Since I am targeting iOS and Android as well, I loose out on the classes Microsoft includes in their latest profiles, until Xamarin updates their profiles.

In order to work around this, I built a custom Timer for the engine, called EngineTimer. It's pretty simple to use and looks like this.

var worldClock = new EngineTimer<IWorld data-preserve-html-node="true">((stateData, clock) => DoSomething(), this);
worldClock.Start(startDelay: 0, interval: 5000);

The EngineTimer is what the Mud Designer will use through-out to handle it's internal state. The Worlds will use one for updating the time of day, Zones will use one for updating their weather conditions, the game class will use one for auto-saving and there will be more usage through-out the engine with it.