Godot

Godot exports to the web as a folder of static files. Upload the folder.

Export #

1. Install the export templates that match your editor version: Editor → Manage Export Templates → Download and Install.

2. Open Project → Export, choose Add, then Web.

3. Set the export path to a folder, with the HTML file named index.html, for example build/index.html. That puts index.html at the top of the build. Godot names every other file after the HTML file (index.js, index.wasm), so keep the names it gives them.

4. Export the project.

5. Put fradiation.json in the export folder, next to index.html. Godot doesn't write it.

   jsonCopy

   {
     "$schema": "https://www.fradiation.games/fradiation.schema.json",
     "viewport": { "width": 1152, "height": 648 },
     "threads": false
   }

   viewport sets the aspect ratio the cabinet letterboxes to. 1152×648 is Godot 4's default window size. See fradiation.json.

If your HTML file has another name, set entry in fradiation.json to that name.

Files in the export #

A Godot 4 web export usually contains these files. The set varies with the Godot version and your export options.

Every one of these has an allowed extension (html, js, wasm, pck, png, json). Run node check-build.mjs build on the folder to confirm. See Builds and uploads.

Threads #

Use Godot 4.3 or later and leave the export preset's Thread Support option off (it's off unless you turn it on). A single-threaded export needs no SharedArrayBuffer, and "threads" stays false.

C# projects #

Godot 4 doesn't support exporting C# projects to the web. Godot's web export docs say so. Check them for your version before you start.

Command line export #

mkdir -p build
godot --headless --export-release "Web" build/index.html

"Web" is the name of the export preset. A relative output path is relative to the folder that holds project.godot, not to the current directory. Pass --path <project folder> to run from elsewhere. For a full build script, see Batch builds.

Filling the frame #

The game runs in an iframe. The cabinet letterboxes it to your viewport and expects the game to fill its window.

• In the Web preset, leave Canvas Resize Policy on Adaptive, its default. Godot then sizes the canvas to the whole browser window, which here is the frame. The default HTML shell fills the window.
• Set the project's stretch settings so the game scales: Project Settings → Display → Window → Stretch. Choose a Mode (canvas_items for 2D, viewport for pixel art) and an Aspect (keep or expand).
• Don't use None unless your own HTML shell sizes the canvas.

Calling the SDK from GDScript #

Godot reaches JavaScript through JavaScriptBridge. The SDK sets window.fradiation, so load it in the page first.

1. Download fradiation-sdk.js into the export folder, next to index.html.

2. In the Web preset, under HTML, set Head Include to:

   htmlCopy

   <script src="fradiation-sdk.js"></script>

   Godot adds Head Include to the <head> of the exported page.

3. Copy fradiation-sdk.js into the folder again if you clear the export folder before exporting.

Save this as fradiation.gd and add it as an autoload named Fradiation in Project Settings. This example is untested on the site.

extends Node

var _fradiation

func _ready() -> void:
	if OS.has_feature("web"):
		_fradiation = JavaScriptBridge.get_interface("fradiation")
		if _fradiation:
			_fradiation.ready()

func unlock_mutation(key: String) -> void:
	if _fradiation:
		_fradiation.unlockMutation(key)

func submit_score(board: String, value: float) -> void:
	if _fradiation:
		_fradiation.submitScore(board, value)

func track(event_name: String) -> void:
	if _fradiation:
		_fradiation.track(event_name)

func ask_for_feedback(prompt: String = "") -> void:
	if _fradiation:
		if prompt.is_empty():
			_fradiation.askForFeedback()
		else:
			_fradiation.askForFeedback(prompt)

Call it from anywhere:

Fradiation.unlock_mutation("boss-down")
Fradiation.submit_score("fastest-clear", elapsed_seconds * 1000.0)

• JavaScriptBridge.get_interface("fradiation") returns the window.fradiation object. Godot has no get_window() method.
• OS.has_feature("web") is false in the editor and on desktop, so those calls do nothing there. Godot's docs recommend this guard.
• Declare every mutation and board key in fradiation.json. A board with "format": "time" takes milliseconds.
• The SDK methods return promises. The example ignores them. Reading a result needs a callback made with JavaScriptBridge.create_callback, which Godot calls with one Array argument. This guide doesn't cover it.
• Outside the site, the SDK resolves every call with defaults. See SDK.

Upload #

Upload the export folder, or a zip of it, on /dev/<slug>. To check and zip in one step, download check-build.mjs (Node 20 or later):

node check-build.mjs pack build Godot.zip

See Publish a game for the upload steps.

Troubleshooting #