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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¶

Promise	`load` ( string basePath )
void	`unload` ( )
boolean	`isWebGLAvailable` ( [ number majorVersion=1 ] )

Instance Methods¶

Promise	`init` ( [ string basePath ] )
Promise	`preloadFile` ( string\|ArrayBuffer file [, string path ] )
Promise	`start` ( EngineConfig override )
Promise	`startGame` ( EngineConfig override )
void	`copyToFS` ( string path, ArrayBuffer buffer )
void	`requestQuit` ( )

class Engine(initConfig)¶

Create a new Engine instance with the given configuration.

Arguments

initConfig (EngineConfig()) -- The initial config for this instance.

Static Methods

Engine.load(basePath)¶

Load the engine from the specified base path.

Arguments

basePath (string()) -- Base path of the engine to load.

Returns

A Promise that resolves once the engine is loaded.

Return type

Promise

Engine.unload()¶

Unload the engine to free memory.

This method will be called automatically depending on the configuration. See unloadAfterInit.

Engine.isWebGLAvailable([majorVersion=1])¶

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

Arguments

majorVersion (number()) -- The major WebGL version to check for.

Returns

If the given major version of WebGL is available.

Return type

boolean

Instance Methods

Engine.prototype.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().

Arguments

basePath (string()) -- Base path of the engine to load.

Returns

A Promise that resolves once the engine is loaded and initialized.

Return type

Promise

Engine.prototype.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.

If not provided, the path is derived from the URL of the loaded file.

Arguments

file (string|ArrayBuffer()) --
The file to preload.

If a string the file will be loaded from that path.

If an 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.

Returns

A Promise that resolves once the file is loaded.

Return type

Promise

Engine.prototype.start(override)¶

Start the engine instance using the given override configuration (if any). startGame can be used in typical cases instead.

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

Fails if a canvas cannot be found on the page, or not specified in the configuration.

Arguments

override (EngineConfig()) -- An optional configuration override.

Returns

Promise that resolves once the engine started.

Return type

Promise

Engine.prototype.startGame(override)¶

Start the game instance using the given configuration override (if any).

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

This will load the engine if it is not loaded, and preload the main pck.

This method expects the initial config (or the override) to have both the executable and mainPack properties set (normally done by the editor during export).

Arguments

override (EngineConfig()) -- An optional configuration override.

Returns

Promise that resolves once the game started.

Return type

Promise

Engine.prototype.copyToFS(path, buffer)¶

Create a file at the specified path with the passed as buffer in the instance's file system.

Arguments

path (string()) -- The location where the file will be created.
buffer (ArrayBuffer()) -- The content of the file.

Engine.prototype.requestQuit()¶

Request that the current instance quit.

This is akin the user pressing the close button in the window manager, and will have no effect if the engine has crashed, or is stuck in a loop.

Engine configuration¶

An object used to configure the Engine instance based on godot export options, and to override those in custom HTML templates if needed.

Properties¶

type	name
boolean	`unloadAfterInit`
HTMLCanvasElement	`canvas`
string	`executable`
string	`mainPack`
string	`locale`
number	`canvasResizePolicy`
Array.<string>	`args`
function	`onExecute`
function	`onExit`
function	`onProgress`
function