HTML5 shell class reference

Projects exported for the Web expose the Engine class to the JavaScript environment, that allows fine control over the engine’s start-up process.

This API is built in an asynchronous manner and requires basic understanding of Promises.

Engine

The Engine class provides methods for loading and starting exported projects on the Web. For default export settings, this is already part of the exported HTML page. To understand practical use of the Engine class, see Custom HTML page for Web export.

Static Methods

PromiseEngine.load ( string basePath )
voidEngine.unload ( )
booleanEngine.isWebGLAvailable ( [ number majorVersion=1 ] )
voidEngine.setWebAssemblyFilenameExtension ( string extension )

Instance Properties

Emscripten Moduleengine.rtenv

实例方法

EngineEngine ( )
Promiseengine.init ( [ string basePath ] )
Promiseengine.preloadFile ( string|ArrayBuffer file [, string path ] )
Promiseengine.start ( [ string arg1, string arg2, … ] )
Promiseengine.startGame ( string execName, string mainPack )
voidengine.setUnloadAfterInit ( boolean enabled )
voidengine.setCanvas ( HTMLCanvasElement canvasElem )
voidengine.setCanvasResizedOnStart ( boolean enabled )
voidengine.setLocale ( string locale )
voidengine.setExecutableName ( string execName )
voidengine.setProgressFunc ( function callback )
voidengine.setStdoutFunc ( function callback )
voidengine.setStderrFunc ( function callback )

Static Method Descriptions

Engine.``load(basePath)

Load the engine from the specified base path.

参数:
  • basePath (string) — 引擎加载的底层路径。
返回:

当引擎加载时承诺解决。

Engine.``unload()

卸载引擎以释放内存。

This method is called automatically once the engine is started unless explicitly disabled using engine.setUnloadAfterInit().

Engine.``isWebGLAvailable([majorVersion = 1])

Check whether WebGL is available. Optionally, specify a particular version of WebGL to check for.

参数:
  • majorVersion (number) — The major WebGL version to check for. Defaults to 1 for WebGL 1.0.
返回:

如果WebGL的主要版本可用，则为真，否则为假。

Engine.``setWebAssemblyFilenameExtension(extension)

Set an alternative filename extension for the WebAssembly module. By default it is assumed to be wasm.

参数:
  • extension (string) — 文件名扩展没有前面的点。

实例属性描述

engine.``rtenv

The runtime environment provided by Emscripten’s Module. For more information refer to the official documentation on Emscripten.

Instance Method Descriptions

class Engine()

Create a new instance of the Engine class.

engine.``init([basePath])

Initialize the engine instance. Optionally, pass the base path to the engine to load it, if it hasn’t been loaded yet. See Engine.load().

参数:
  • basePath (string) — 引擎加载的底层路径。
返回:

承诺一旦加载并初始化引擎就会解析。

engine.``preloadFile(file[, path])

Load a file so it is available in the instance’s file system once it runs. Must be called before starting the instance.

参数:
  • file (string|ArrayBuffer) —

    If type is string, the file will be loaded from that path.

    If type is ArrayBuffer or a view on one, the buffer will used as the content of the file.

  • path (string) — Path by which the file will be accessible. Required, if file is not a string. If not passed, the path is derived from the URL of the loaded file.
返回:

Promise that resolves once the file is loaded.

engine.``start([arg1, arg2, …])

Start the instance of the engine, using the passed strings as command line arguments. engine.startGame() can be used in typical cases instead.

This will initialize the instance if it is not initialized. For manual initialization, see engine.init(). The engine must be loaded beforehand.

Fails if a canvas cannot be found on the page.

参数:
  • variadic (string) — Command line argument.
返回:

引擎启动后解析的承诺。

engine.``startGame(execName, mainPack)

Start the game instance using the given executable URL and main pack URL.

This will initialize the instance if it is not initialized. For manual initialization, see engine.init().

This will load the engine if it is not loaded. The base path of the executable URL will be used as the engine base path.

参数:
  • execName (string) — Executable name in a form of URL, omitting filename extension.
  • mainPack (string) — URL of the main pack to start the game.
返回:

当游戏启动后承诺解析。

engine.``setUnloadAfterInit(enabled)

Specify whether the engine will be unloaded automatically after the instance is initialized. Enabled by default.

参数:
  • enabled (boolean) — 如果引擎在初始化后卸载，则为“真”，否则为“假”。

engine.``setCanvas(canvasElem)

Specify a canvas HTML element to use. By default, the first canvas element on the page is used for rendering.

参数:
  • canvasElem (HTMLCanvasElement) — The canvas element to use.

engine.``setCanvasResizedOnStart(enabled)

Specifies whether the canvas will be resized to the width and height specified in the project settings on start. Enabled by default.

参数:
  • enabled (boolean) — 如果在开始时需要调整画布大小，则为”真”，否则为“假”。

engine.``setLocale(locale)

Specify a language code to select the proper localization for the game.

参见

Complete list of supported locales.

参数:
  • locale (string) — 语言代码。

engine.``setExecutableName(execName)

Specify the virtual filename of the executable. By default, the base name of the loaded engine files is used.

This affects the output of OS.get_executable_path() and sets the automatically started main pack to *ExecutableName*.pck.

参数:
  • execName (string) — 可执行文件名称。

engine.``setProgressFunc(callback)

Specify a callback function for displaying download progress. The callback function is called once per frame, so that the usage of requestAnimationFrame() is not necessary.

If the callback function receives a total amount of bytes as 0, this means that it is impossible to calculate. Possible reasons include:

  • 文件随服务器端分块压缩一起提供
  • 文件在Chromium上通过服务器端压缩提供
  • 并非所有文件下载都已开始(通常在没有多线程的服务器上)
参数:
  • callback (function) — The callback function must accept two numeric arguments: the amount of bytes loaded so far, and the total number of bytes to load.

engine.``setStdoutFunc(callback)

Specify a callback function for handling the standard output stream. This method should usually only be used in debug pages. By default, console.log() is used.

参数:
  • callback (function) — The callback function must accept one string argument: the message to print.

engine.``setStderrFunc(callback)

Specify a callback function for handling the standard error stream. This method should usually only be used in debug pages. By default, console.warn() is used.

参数:
  • callback (function) — The callback function must accept one string argument: the message to print.