The Manager for your ECSx application.

In an ECSx application, the Manager is responsible for:

• starting up ETS tables for each Component Type, where the Components will be stored
• prepopulating the game content into memory
• keeping track of the Systems to run, and their run order
• running the Systems every tick

components-0-and-systems-0

components/0 and systems/0

Your Manager module must contain two zero-arity functions called components and systems which return a list of all Component Types and Systems in your application. The order of the Component Types list is irrelevant, but the order of the Systems list is very important, because the Systems are run consecutively in the given order.

setup-0-and-startup-0

setup/0 and startup/0

Manager modules may also implement two optional functions for loading all the necessary component data for your app before any Systems run or users connect.

The setup/0 function runs only once, when you start your app for the first time, while the startup/0 function runs every time the app starts, including the first (after setup/0 is run). The Manager uses the Persistence layer to determine if this is a fresh server or a subsequent start.

These functions will be run during the Manager's initialization. The Component tables will be created before they are executed.

example

Example

defmodule YourApp.Manager do
  use ECSx.Manager

  def setup do
    for tree <- YourApp.Map.trees() do
      YourApp.Components.XPosition.add(tree.id, tree.x_coord, persist: true)
      YourApp.Components.YPosition.add(tree.id, tree.y_coord, persist: true)
      YourApp.Components.Type.add(tree.id, "Tree", persist: true)
    end
  end

  def startup do
    for spawn_location <- YourApp.spawn_locations() do
      YourApp.Components.SpawnLocation.add(spawn_location.id)
      YourApp.Components.Type.add(spawn_location.id, spawn_location.type)
      YourApp.Components.XPosition.add(spawn_location.id, spawn_location.x_coord)
      YourApp.Components.YPosition.add(spawn_location.id, spawn_location.y_coord)
    end
  end
end