Exportieren für das Web

HTML5 export allows publishing games made in Godot Engine to the browser. This requires support for WebAssembly and WebGL in the user's browser.

Wichtig

Use the browser-integrated developer console, usually opened with F12, to view debug information like JavaScript, engine, and WebGL errors.

Achtung

Many browsers, including Firefox and Chromium-based browsers, will not load exported projects when opened locally per file:// protocol. To get around this, use a local server.

Tipp

Python offers an easy method to start a local server. Use python -m http.server 8000 --bind 127.0.0.1 with Python 3 to serve the current working directory at http://localhost:8000.

Achtung

There are significant bugs when running HTML5 projects on iOS (regardless of the browser). We recommend using iOS' native export functionality instead, as it will also result in better performance.

WebGL 2

Until the OpenGL ES 3 renderer is removed from Godot in favor of Vulkan, HTML5 export uses WebGL 2 when the GLES3 option is selected.

Warnung

Using WebGL 2 is not recommended due to its expected removal from Godot without replacement.

WebGL 2 is not supported in all browsers. Firefox and Chromium (Chrome, Opera) are the most popular supported browsers, Safari and Edge do not work. On iOS, all browsers are based on WebKit (i.e. Safari), so they will also not work.

Godot's WebGL 2 renderer has issues with 3D and is no longer maintained.

Limitierungen

For security and privacy reasons, many features that work effortlessly on native platforms are more complicated on the web platform. Following is a list of limitations you should be aware of when porting a Godot game to the web.

Using cookies for data persistence

Users must allow cookies (specifically IndexedDB) if persistence of the user:// file system is desired. When playing a game presented in an iframe, third-party cookies must also be enabled. Incognito/private browsing mode also prevents persistence.

The method OS.is_userfs_persistent() can be used to check if the user:// file system is persistent, but can give false positives in some cases.

Aufnahme des gesamten Bildschirms und der Maus

Browsers do not allow arbitrarily entering full screen. The same goes for capturing the cursor. Instead, these actions have to occur as a response to a JavaScript input event. In Godot, this means entering full screen from within a pressed input event callback such as _input or _unhandled_input. Querying the Input singleton is not sufficient, the relevant input event must currently be active.

For the same reason, the full screen project setting doesn't work unless the engine is started from within a valid input event handler. This requires customization of the HTML page.

Audio autoplay

Chrome restricts how websites may play audio. It may be necessary for the player to click or tap or press a key to enable audio.

Siehe auch

Google offers additional information about their Web Audio autoplay policies.

HTTPClient und HTTPRequest

The HTTP classes have several restrictions on the HTML5 platform:

  • Der Zugriff auf den StreamPeer ist nicht möglich
  • Threaded/Blocking-Modus ist nicht verfügbar
  • Der Fortschritt kann nicht mehr als einmal pro Frame ausgeführt werden, sodass die Abfrage in einer Schleife einfriert
  • No chunked responses
  • Die Host-Verifizierung kann nicht deaktiviert werden
  • Subject to same-origin policy

Exportierte .html Datei darf nicht wiederverwendet werden

Each project must generate their own HTML file. On export, several text placeholders are replaced in the generated HTML file specifically for the given export options. Any direct modifications to the generated HTML file will be lost in future exports. To customize the generated file, see Eigene HTML Seiten für Web Export.

Boot splash is not displayed

The default HTML page does not display the boot splash while loading. However, the image is exported as a PNG file, so custom HTML pages can display it.

Einschränkungen der Shader-Sprache

When exporting a GLES2 project to HTML5, WebGL 1.0 will be used. WebGL 1.0 doesn't support dynamic loops, so shaders using those won't work there.

Unimplemented functionality

The following functionality is currently unavailable on the HTML5 platform:

  • Threads
  • GDNative
  • C#
  • Clipboard synchronization between engine and operating system
  • andere Netzwerke als HTTPClient and WebSocketClient

Tipp

Check the list of open HTML5 issues on GitHub to see if the functionality you're interested in has an issue yet. If not, open one to communicate your interest.

Serving the files

Exporting for the web generates several files to be served from a web server, including a default HTML page for presentation. A custom HTML file can be used, see Eigene HTML Seiten für Web Export.

The generated .html file can be used as DirectoryIndex in Apache servers and can be renamed to e.g. index.html at any time, its name is never depended on by default.

The HTML page draws the game at maximum size within the browser window. This way it can be inserted into an <iframe> with the game's size, as is common on most web game hosting sites.

The other exported files are served as they are, next to the .html file, names unchanged. The .wasm file is a binary WebAssembly module implementing the engine. The .pck file is the Godot main pack containing your game. The .js file contains start-up code and is used by the .html file to access the engine. The .png file contains the boot splash image. It is not used in the default HTML page, but is included for custom HTML pages.

The .pck file is binary, usually delivered with the MIME-type application/octet-stream. The .wasm file is delivered as application/wasm.

Vorsicht

Delivering the WebAssembly module (.wasm) with a MIME-type other than application/wasm can prevent some start-up optimizations.

Delivering the files with server-side compression is recommended especially for the .pck and .wasm files, which are usually large in size. The WebAssembly module compresses particularly well, down to around a quarter of its original size with gzip compression.

Export options

Wenn eine ausführbare Web-Exportvorlage verfügbar ist, wird im Editor eine Schaltfläche zwischen den Schaltflächen Szene stoppen und Bearbeitete Szene abspielen angezeigt, um das Spiel schnell im Standardbrowser zum Testen zu öffnen.

If a path to a Custom HTML shell file is given, it will be used instead of the default HTML page. See Eigene HTML Seiten für Web Export.

Head Include is appended into the <head> element of the generated HTML page. This allows to, for example, load webfonts and third-party JavaScript APIs, include CSS, or run JavaScript code.

Aufruf von JavaScript aus dem Skript

In Webbuilds ist der JavaScript-Singleton implementiert. Es bietet eine einzige Methode namens "eval", die ähnlich wie die gleichnamige JavaScript-Funktion funktioniert. Es nimmt eine Zeichenfolge als Argument und führt sie als JavaScript-Code aus. Dies ermöglicht die Interaktion mit dem Browser auf eine Weise, die mit in Godot integrierten Skriptsprachen nicht möglich ist.

func my_func():
    JavaScript.eval("alert('Calling JavaScript per GDScript!');")

Der Wert der letzten JavaScript-Anweisung wird in einen GDScript-Wert konvertiert und unter bestimmten Umständen von `` eval () `` zurückgegeben:

  • JavaScript `` Nummer`` wird als GDScript zurückgegeben: ref: class_float
  • JavaScript boolean is returned as GDScript bool
  • JavaScript string is returned as GDScript String
  • JavaScript ArrayBuffer, TypedArray and DataView are returned as GDScript PoolByteArray
func my_func2():
    var js_return = JavaScript.eval("var myNumber = 1; myNumber + 2;")
    print(js_return) # prints '3.0'

Any other JavaScript value is returned as null.

HTML5 export templates may be built without support for the singleton. With such templates, and on platforms other than HTML5, calling JavaScript.eval will also return null. The availability of the singleton can be checked with the JavaScript feature tag:

func my_func3():
    if OS.has_feature('JavaScript'):
        JavaScript.eval("""
            console.log('The JavaScript singleton is available')
        """)
    else:
        print("The JavaScript singleton is NOT available")

Tipp

GDScript's multi-line strings, surrounded by 3 quotes """ as in my_func3() above, are useful to keep JavaScript code readable.

The eval method also accepts a second, optional Boolean argument, which specifies whether to execute the code in the global execution context, defaulting to false to prevent polluting the global namespace:

func my_func4():
    # execute in global execution context,
    # thus adding a new JavaScript global variable `SomeGlobal`
    JavaScript.eval("var SomeGlobal = {};", true)