Before dealing with the asynchronous functions (referred to from now on as async functions) in GameMaker Studio 2 it may be that you are wondering what the word "asynchronous" actually means! Well, the actual dictionary definition of asynchronous is:
"pertaining to a transmission technique that does not require a common clock between the communicating devices; timing signals are derived from special characters in the data stream itself."
In the context of GameMaker Studio 2, an async function is one that sends out to a web server, or asks for user input, or even streams data, while letting GameMaker Studio 2 continue to run without blocking. When the information callback is received a special Async Event is fired which, in turn, allows any instance with an Async Event assigned to it to execute further functions (although this does not have to be the case). So, basically, it's a way to communicate with some external resource (server, user or device) without the game or project blocking while waiting for a reply.
Why is this important? Well, since it allows GameMaker Studio 2 to continue functioning while sending or receiving data, and this means that you can do many things all without blocking the game loop like -
- stream data from the device into your game without the player waiting for things to load
- have callback events to do things only when the correct information is received
- communicate and interchange data with a web server
This all makes everything function in a much more fluid and unobtrusive way. It should be noted that the Async Events will be triggered for all instances that have them, so you can use an async function in one instance, and have the Asynchronous Event that deals with the reply in another one, or even various other ones. You can go here for more information on how the Asynchronous event works - Asynchronous Events.
The different type of asynchronous functions are listed in the sections below:
Below you can find a list of the Async http functions available in GameMaker Studio 2:
Please note that the above http_ functions may not function as expected due to cross domain security issues. This means that requests to your server or attempts to load resources from across domains are blocked and may appear to return blank results or 404 errors. One of the ways you can get around this is to have some server side PHP which allows certain domains to access your server (this is also a way to protect your resources and block servers that are not included in the PHP allow list).
The following is an example of the code you can use for this:
$http_origin = $_SERVER['HTTP_ORIGIN'];
if ($http_origin == "http://127.0.0.1:51268")
For image load requests where determining or setting their cross-origin type is important, the following functions exist:
In most cases these functions should not need to be used, but if the game is stored on a secured server - where certain assets may require basic authentication to be accessed and are generating security errors when loading - setting the cross-origin type for image requests to "use-credentials" may be necessary (as opposed to the default "anonymous" setting).
Previous versions of GameMaker had pop-up dialogues that blocked the runner while waiting for a response from the user. However most modern devices do not like this and will interpret the runner stopping as an error and close the app. To prevent this GameMaker Studio 2 has async equivalents of these functions that fulfil the same purpose as previous versions, but do not block the game runner at any time, meaning that when called the game will run as normal in the background while the user responds to the shown dialogue. Once the user has responded, a Dialogs Asynchronous Event will be called so that you can deal with the results.
Below is a list of all the available asynchronous dialogue functions:
在游戏开发过程中，常常需要将游戏的状态信息保存在特定类型的文件中，但是把这些信息保存在本地设备上在大多数时候并不是一个好的选择，因为当玩家在卸载游戏之后重新安装时，这些数据可能会丢失。为了防止这种情况的出现你可以使用各种不同的云服务 ，用来提供可以修改和检索数据的云端据存储服务。You should note that this function is limited to one single data "blob" per game, so every time you send a new save to the cloud service, whether it is a string or a file, it will overwrite any previously stored data.
GameMaker Studio 2 supports this with a few simple functions that work in conjunction with the Asynchronous Cloud Event. 下面的网页将详细介绍这些函数：NOTE: Currently only the Android target uses these functions, and you need to tick the Enable Google Cloud Saving checkbox in the Social section of the Android Game Options. This will prompt you to download the Google Services extension, which is required for cloud saving on Android to function. For more information on Cloud Saving please see the following helpdesk article:
在移动设备上,通常只有一个应用程序可以在任何时候活跃在前台,但是许多的游戏和应用程序需要基于时间或者其他特定的用户行为来触发事件， 并且不需要活跃在前台。In these cases, Local and Remote push notifications can allow these games to notify their users when events occur.
当操作系统推送了一个本地或远程的通知而目标程序并没有在前台运行时，通知将会以banner(横幅) 的形式来展示。If there is a notification alert and the user taps on it, then the game is launched and an Asynchronous Push Event is called where you can check the callback string that you specify and resolve the push based on its value. If the application is running in the foreground when the notification is delivered, the application will still receive an Asynchronous Push Event, but the user will get no message displayed unless you create it yourself.
There are a few differences to note between supported platforms:
- On Android, all notifications received when the app is not running/in background, will be stored, and the data delivered by the async event the next time the app runs and you will need to enable push notifications within the Android Game Options for them to work.
- On iOS, data for a particular notification will only be delivered when the notification is selected (or if the app is running in foreground when the notification is received) and you will need to enable push notifications within the iOS Game Options for them to work.
本地通知由安装游戏的设备直接推送，并不需要后端服务器。你仅仅需要设置时间日期和通知内容，如果你的程序当前没有在运行的话，通知就会被推送。You simply set the date and time for the notification and it will be displayed to the user if the game is not currently running. This type of notification is useful to set "reminders" for the user to play your game again, or to offer a daily reward for playing, etc... and when the user taps the notification it will launch the game and pass in a data string which can then be parsed by the game to give a reward or whatever.
远程通知由对应平台的应用商店提供的推送服务发送，通知将会被发送到所有安装了你的应用的设备上。This is supported by GameMaker Studio 2 on the iOS and Android target modules.
There are no functions in GameMaker Studio 2 to deal with remote notifications, as they must all be generated by your server and handled by the respective App Stores. However, once set up correctly, GameMaker Studio 2 games will receive these notifications, which can then be dealt with in the Asynchronous Push Event, as you would a local notification.
For all available platforms, once you have done the necessary set-up, when the game is run on a device it will register that device with the platforms push notification service. This will trigger an Asynchronous Push Notification Event, and the ds_map key "type" will have the value "register" as well as a new key, "reg_id", containing the registration id (or an error message in the "error" key, if "status" is 0). 你必须发送这个注册ID（registration id）到你的服务器，每个设备都拥有独一无二的注册ID（registration id）。Your server must maintain a list of ids for registered devices, as when when you send a push notification message from your server, you use the registration ids to send the message to the registered devices.
请注意，远程推送通知不能保证一定传递成功，并且允许传送的数据的负载也非常小。This varies between platforms, but iOS is particularly limited - the apple service only delivers the most recent notification, which must be selected by the recipient for the payload data to be delivered to your async event, and these notifications have a maximum payload size of 256bytes. 举个例子，通常一个远程推送式通知就表明服务器上有新的数据。注意： Android requires that you add the GCM Sender ID into the Android Game Options. Project Number 在你创建安卓工程时被创建。
For further details on how to go about setting up a server, as well as information specific to the available platforms, please see this article on the YoYo Games Helpdesk.注意： Implementing the server-side is entirely up to the end user, and YoYo Games do not provide any support for that side of things, other than basic set-up information available from their Knowledge Base.
As the mobile platforms grow and take up more of the gaming market share, so to does the demand for social interaction and feedback from these games. To meet these demands GameMaker Studio 2 has certain 3rd party APIs integrated into it to permit you to communicate with different networks depending on the device you are targeting for your game.
The following sections contain information on the available social media integration:
There is also an asynchronous function that will open a dialogue and permit you to request that a user of your game leaves a comment or rating on a specific web page: