Originally published as an Advisory Hour Substack post on 2026-10-13. This first-party site copy preserves the text, localizes public supporting media, and connects the record to its project trail.
Original post
With Waymark working reasonably well, I got to thinking about the other sensors and capabilities on a mobile phone. What could I do with them through a web browser that I hadn’t tried yet?
That was the question one night. What if the phone’s motion sensors could detect tilting and turning, and the microphone could detect you blowing into it? Could you use those together to make a glassblowing game?
The thought was ridiculous enough that I had to see how it would work.
So, with a little back and forth with a very capable AI model, I ended up with Breathglass: The Singing Furnace. It’s now in the catalog of experiments, and I don’t really know what else to say other than how fantastic and slightly insane this is.
You blow across the microphone, and a bubble of molten glass grows on the end of a pipe. Tilt the phone and the soft glass stretches or settles under gravity. Swing it and you can draw the piece out longer. You also have to keep the pipe turning, because otherwise the glass starts to sag.
Then there’s the camera. Point it toward a lamp or a bright window, and that light becomes a way to reheat the glass in the game. You can even sample colors from the room you’re standing in.
The part that makes this particularly fun is that you’re trying to make a vessel that sings a particular note. As the bubble grows, its pitch drops. Changing the body or squeezing the neck changes the sound. The pitch is calculated from the shape you’ve made, so you can watch the tuner or try to get there by ear.
If you keep a finished piece, it goes on your shelf. Tap it and it rings. Blow into the microphone and the shelf becomes a little bottle organ. You can hum a note and have a matching vessel answer you.
I can understand the broader concept of using a microphone as an input. I’m sure plenty of this was possible before. But getting the glass itself to change shape, respond to movement, and produce a sound based on that shape is still pretty amazing to me.
There’s a practice room to help you get used to the controls, and buttons or keyboard controls if you’d rather try it on a computer. Everything runs in the browser. The microphone and camera are analyzed as you play, without recording them.
I encourage you to check it out. There are undoubtedly going to be some sharp corners in the application, unlike your glass project, which hopefully comes out round and doesn’t break on you.
It’s a strange experiment, and it’s worth imagining what kinds of things the phone can do that maybe was just out of reach before.
Play now: Breathglass: The Singing Furnace | GameLab
Read more: https://ericrhea.com/gamelab/breathglass.html
Connected work
- Breathglass Build Notes: Read how the furnace, glass physics, and singing vessels were made.
- Play Breathglass: Shape a vessel and hear the note it sings.