Stadia Controller’s Two Extra Buttons Get Seen With WebHID

The Google Stadia game streaming service relied on a proprietary controller. It was a pretty neat piece of hardware that unfortunately looked destined for landfills when Google announced that Stadia would discontinue. Thankfully it’s possible to use them as normal gamepads, and related to that, [Thomas Steiner] has a developer blog post about how to talk to the Stadia controller via WebHID.

(First, a quick recap: Bluetooth mode is a custom firmware that transforms a Stadia controller from proprietary device into standard gamepad that can be connected via USB cable, or wirelessly over Bluetooth.)

But here’s the thing: standard gamepads have 17 total buttons, but the Stadia controller actually has 19 (the extra two are the Assistant and Capture buttons near the center of the unit.)  Those two extra buttons are perfectly functional, but the standard Gamepad API only acknowledges buttons 0-16.

That’s where the WebHID API comes in, allowing one to talk to the two additional Stadia buttons. The Gamepad API handles all the usual gamepad stuff, and the WebHID API can access events like button down and button up for the two additional buttons not covered by the Gamepad API. There’s a demo and source code demonstrating it all working together.

Google’s termination of Stadia left a sour taste in many mouths. But efforts like this to keep the controllers out of landfills are a good direction, even if they don’t really erase the perception of Google as an organization with a penchant for killing off products that customers actively use.