@gd-kirie/platform

@gd-kirie/platform exposes browser-side desktop capabilities supplied by the Godot host. Create the client from an existing @gd-kirie/ipc-eventa context.

import { createContext } from "@gd-kirie/ipc-eventa";
import { createPlatformClient, hostWindowPointerPositionChanged } from "@gd-kirie/platform";

const eventa = createContext();
const platform = createPlatformClient(eventa.context);

await platform.hostWindow.setAlwaysOnTop(true);

const windowBounds = await platform.hostWindow.getBounds();
const displayBounds = await platform.hostWindow.getCurrentDisplayBounds();
const stopPointer = eventa.context.on(hostWindowPointerPositionChanged, ({ body }) => {
  console.log(body);
});
const pointer = await platform.hostWindow.getPointerPosition();
const windowState = await platform.hostWindow.getState();
console.log(windowBounds, displayBounds, pointer, windowState);
stopPointer();
eventa.dispose();

Request/response capabilities are methods on the returned client. Host-initiated events are exported @moeru/eventa contracts; subscribe to them on the same context and the returned function unsubscribes.

External URLs

Use openExternalUrl() to open an absolute HTTP or HTTPS URL with the system browser:

await platform.openExternalUrl("https://example.com");

The Godot host rejects relative URLs and other URI schemes. It uses OS.shell_open() to select the system browser.

Use openApplicationDataDirectory() to open the current Godot application's data directory and receive its absolute path:

const path = await platform.openApplicationDataDirectory();

This capability does not accept an arbitrary path.

Host window

• window position and size in screen coordinates
• current display position and size in screen coordinates
• pointer position relative to the host window, including while it is click-through
• pointer passthrough
• native move and resize gestures
• always-on-top
• centering on the current display
• visibility, focus, and minimized-state snapshots and change events

Pointer coordinates use host-window pixels and are not normalized to the browser viewport. Subscribe to hostWindowPointerPositionChanged first. Then call getPointerPosition() to get a snapshot and start native observation. The host sends later changes while the window is unfocused or click-through.

getState() returns one lifecycle snapshot and starts native state observation. Call it once during setup. Later changes arrive as hostWindowStateChanged events; subscribe with context.on(hostWindowStateChanged, ({ body }) => ...) and call the returned function to unsubscribe.

Global shortcuts

The macOS and Windows hosts can register a shortcut that remains active while the Godot window is hidden or unfocused:

const shortcut = {
  keycode: 0x4b, // Godot Key.K
  shiftPressed: false,
  altPressed: false,
  ctrlPressed: false,
  metaPressed: false,
  commandOrControlAutoremap: true,
};

await platform.globalShortcuts.register(shortcut, ({ state }) => {
  console.log(state); // "pressed" or "released"
});

await platform.globalShortcuts.unregister(shortcut);

keycode uses Godot's logical Key values. Every modifier field is required; commandOrControlAutoremap selects Command on macOS and Control on Windows. One onKeyEvent handler receives both states; keyboard auto-repeat does not produce extra calls.

System back

Android delivers the system Back button as a Platform event. The application decides what Back means:

import { backRequested } from "@gd-kirie/platform";

const stop = context.on(backRequested, () => {
  console.log("The system Back button was pressed.");
});

stop();

To handle Back instead of letting Android close the application, set SceneTree.quit_on_go_back to false. The event is not emitted on platforms without a system Back button.