View Source Ecspanse.Template.Component.Timer (ECSpanse v0.9.0)

The Timer is a Template Component designed to facilitate the creation of custom timer (countdown) components.

It serves as a foundation for building custom timer components with use Ecspanse.Template.Component.Timer.

The framework automatically decrements the Timer's time each frame, eliminating the need for manual updates. However, manual resetting may be necessary under certain circumstances such as:

  • When game logic requires custom resetting.
  • When the timer mode is set to :once, necessitating manual reset after reaching 0.

A dedicated Ecspanse.System.Timer system is provided by the framework. This system auto-decrements the Timer component's time and dispatches an event when time reaches 0. To ensure functionality, this System must be manually included in the Ecspanse.setup/1. Note that it should be added as a sync system, either at frame start or end. This design choice allows developers control over timer operation based on specific states or conditions. For instance, pausing the timers when the game is in a pause state or other game states.

Pause control at a granular level can be achieved by setting the paused field to true.

The Timer component template comes with a predefined state comprising of:

  • :duration - the timer's duration in milliseconds which also serves as the reset value.
  • :time - the current time of the timer in milliseconds, auto-decremented by the framework each frame.
  • :event - the event module dispatched when timer reaches 0.
    • create special timer events using Ecspanse.Template.Event.Timer.
    • these events require no options.
    • their state is predefined to %CustomEventModule{entity_id: entity_id}, where entity refers to owner of the custom timer component.
    • event batch key corresponds to the component's owner entity's id.
  • :mode - defines how timer operates and can be one of:
    • :repeat (default) - timer resets to original duration after reaching 0 and repeats indefinitely.
    • :once - timer runs once and pauses after reaching 0. Time value needs manual reset.
    • :temporary: Timer runs once and removes itself from entity after reaching 0.
  • paused: A boolean indicating if timer is paused (defaults to false).

Example: 

  defmodule Demo.Components.RestoreEnergyTimer do
    use Ecspanse.Template.Component.Timer,
      state: [duration: 3000, time: 3000, event: Demo.Events.RestoreEnergy, mode: :repeat, paused: false]
  end

  defmodule Demo.Events.RestoreEnergy do
    use Ecspanse.Template.Template.Event.Timer
  end
end

See a working example in the tutorial