Hingewave
The iPhone Duo fold animation for your MacBook lid, Windows laptop and Android foldable.
Close the lid and the desktop stays anchored in space while the glass tilts over it, frosting and darkening from the hinge outward. Open it and the picture comes back. The physical hinge is the timeline: Hingewave reads the angle sensor every 20 ms and redraws on the GPU, so the motion of your hand is the motion on screen.
That clip is a render, not a recording. The screen content is real output from core/reference at the tuned settings, composited into a generated laptop; the machine, the desk and the lighting are synthetic. What the app does on a real Mac is the GIF above.
One repository, three native apps, one shared definition of the effect. Every port passes the same motion fixtures and the same golden render check in CI.
Install
macOS
curl -fsSL https://raw.githubusercontent.com/Ant-lib/hingewave/main/macos/install.sh | bash
That downloads the latest release, verifies its checksum, puts Hingewave in Applications and opens it. A laptop icon appears in the menu bar and macOS immediately asks for Screen Recording: click Open System Settings and turn on Hingewave under Privacy and Security, Screen Recording. Now close the lid slowly. Releases are signed with one stable certificate, so the grant survives updates; an installer cannot grant it for you, macOS only allows the app to ask.
Homebrew users: brew tap ant-lib/tap then brew install --cask ant-lib/tap/hingewave. Homebrew 6 asks you to trust third-party taps first with brew trust ant-lib/tap.
Be aware of what both installers do: because the app is not notarized, the script and the cask remove Gatekeeper's quarantine flag from Hingewave.app after verifying the checksum, so the first launch is not blocked. If you would rather keep Gatekeeper in the loop, use the manual zip route below and approve the app yourself.
Prefer a manual install? Download Hingewave-mac.zip from Releases, unzip, and drag Hingewave.app into Applications. The app is not notarized, so on first open go to System Settings, Privacy and Security, and click Open Anyway.
Requirements: macOS 14 Sonoma or later and a MacBook with a lid angle sensor. That is the 2019 16-inch MacBook Pro and later, MacBook Air with M2 or later, and 14-inch or 16-inch MacBook Pro with M1 Pro or later. The M1 MacBook Air and the 13-inch M1 and M2 MacBook Pro have no continuous sensor; the menu says so and the app stays idle.
Android
Download hingewave-.apk from Releases and install it, or add this repository in Obtainium to get updates. Open Hingewave, pick a picture or keep the built-in one, and tap Set as live wallpaper. Then fold the phone slowly.
It is a live wallpaper, so it needs no accessibility service, no overlay permission and no screen capture. Only the wallpaper folds; icons stay sharp. On the inner screen the moving half folds about the centre line while the other half stays still; on the cover screen the whole panel frosts as the phone opens.
Another render rather than a photograph, and a generic foldable rather than any particular phone. The picture on the panel is real: 140 degrees was put through the inner panel mapping in core/effect.json, which gives tilt 40 and progress 0.44, and the moving half was rendered by core/reference with the hinge on the crease. Hingewave has not run on foldable hardware yet, only on the emulator.
Requirements: Android 13 or later. The fold follows the hinge on foldables whose sensor reports continuous angles to apps: the Galaxy Z Fold 8 and the Pixel Fold family. The Galaxy Z Fold 7 and earlier, Z Flip 5 and 6, and the Z TriFold expose only 0, 90 and 180 degrees to third-party apps. Hingewave detects that and switches to Splash: a ripple leaves the hinge the moment the phone starts opening or closing, keeps breathing while you handle it, and drains away after five seconds without movement. Splash can also be picked by hand in the settings screen on any device.
Windows
Download hingewave-x64.exe (or hingewave-arm64.exe for Snapdragon laptops) from Releases and run it. A laptop icon appears in the tray. The winget manifest under windows/winget is submitted with each release, after which winget install Ant-lib.Hingewave works too.
The executable is not code signed, so SmartScreen shows "Windows protected your PC" the first time: click More info, then Run anyway. Verify the download against SHA256SUMS-windows.txt if you prefer.
Windows laptops rarely have a hinge angle sensor, so Hingewave picks the best source it can find and shows it in the tray menu:
| Tier | Source | What you get |
|---|
| 1 | Hinge angle sensor (Windows.Devices.Sensors.HingeAngleSensor) | The real thing, continuous |
| 2 | Lid accelerometer, present on most convertibles and 2-in-1s | Continuous angle with the base assumed level; run Calibrate lid sensor once from the tray menu |
| 3 | Lid switch only | A fixed 0.6 second transition on close and open |
Requirements: Windows 10 version 2004 or later, a primary display, and Windows Graphics Capture (built in since 2004).
Using it
macOS
The menu has four items. Follow the Lid turns the effect off and on. Preview Fold plays a scripted close and reopen so you can see the effect without touching the lid; before Screen Recording is granted it folds a generated picture instead of your desktop. Launch at Login does what it says. Quit quits.
Good to know:
- It starts from wherever your lid rests, 105 degrees or 130: once the lid has closed 5 degrees from that angle at a deliberate pace, the effect begins. A nudge while typing is too slow to trigger it.
- Stop part way and the desktop clears back after two seconds, so you can work at any angle.
- Reopen before the Mac sleeps and the effect plays in reverse. Once it has slept, waking ends the effect immediately.
- With an external monitor attached, the effect ends when the built-in display switches off. Nothing lands on the monitor.
- Reduce Motion in System Settings disables the tilt; blur and darkening still follow the lid.
How it works
| Piece | Role |
|---|
core/effect.json | The tuned numbers: eye distance, blur, darkening, spring, angles. One file for every platform. |
core/reference/ | Python reference implementation of the motion model and the shader math. Generates the fixtures and golden images every port must pass. |
macos/Sources/Hingewave/LidAngleSensor.swift | Reads the hinge angle over IOKit HID (usage page 0x20, usage 0x8A). Hundredths of a degree on Apple silicon. No permission needed. |
macos/Sources/HingewaveCore/LaptopMotionModel.swift | Critically damped spring plus the idle, armed, active, clearing state machine. Verified against core/fixtures. |
macos/Sources/Hingewave/ScreenStreamer.swift | Streams the built-in display through ScreenCaptureKit into Metal textures. Runs only while the lid moves. |
macos/Sources/Hingewave/FoldShader.swift | One Metal fragment pass: perspective hold onto the resting plane, mip-chain blur growing from the hinge, darkening. Verified against core/golden by PSNR. |
macos/Sources/Hingewave/OverlayWindow.swift | Click-through window over the built-in display, excluded from every screen capture so it never feeds back into its own picture. |
The full design, including the math, is in docs/design.md.
Privacy
No network access, no analytics, no accounts, on any platform. On macOS and Windows, screen frames go from ScreenCaptureKit or Windows Graphics Capture straight to the GPU and are dropped when the effect clears; screens the system marks secure are not captured. The Android wallpaper captures nothing at all: it only reads the hinge sensor and draws your picture. Event logs (~/Library/Logs/Hingewave.log on macOS, %LOCALAPPDATA%\Hingewave\Hingewave.log on Windows) never contain screen content.
Build from source
macOS
The Xcode Command Line Tools are enough (xcode-select --install). The Metal shader compiles at runtime, so full Xcode is not required.
git clone https://github.com/Ant-lib/hingewave.git
cd hingewave/macos
./build.sh --install --run
./build.sh --universal --zip produces the release zip with an Intel slice. swift test runs the motion model against the shared fixtures. Debug flags on the built binary:
Hingewave --probe 5 print the lid angle for five seconds
Hingewave --render-check /tmp/rc render the golden set through Metal and report PSNR
Hingewave --simulate-close scripted 120 to 0 to 120 sweep over the live desktop
Hingewave --demo the same sweep over a generated picture, no permission needed
Hingewave --preview 45 move to one angle and hold until the effect clears
Android
JDK 17 and the Android SDK (platform 35). cd android && ./gradlew :app:testDebugUnitTest :app:assembleDebug. With a device or emulator attached, ./render-check.sh runs the golden check through the real GPU pipeline and ./emulator-check.sh additionally applies the wallpaper and drives the virtual hinge, saving screenshots into android/build/emulator-shots.
Windows
The .NET 8 SDK. dotnet test windows/Hingewave.Core.Tests runs anywhere, including macOS and Linux; dotnet build windows/Hingewave.App compiles anywhere too. pwsh windows/build.ps1 on Windows publishes the single-file executables, and hingewave.exe --render-check runs the golden check on the WARP software rasteriser. Other flags mirror the macOS ones: --probe, --simulate-close, --demo, --preview .
Shared core
The reference implementation needs Python 3 with NumPy and Pillow: pip install -e "core/reference[test]", then python -m pytest core/reference and, after changing the effect, python -m hingewave_ref regen from core/reference. CI fails if the committed fixtures and goldens are stale. python3 tools/make_demo.py --desktop <picture> re-renders the two README images through the same reference code.
Verified hardware
| Platform | Device | Status |
|---|
| macOS | 14-inch MacBook Pro, M1 Pro, macOS 26 | Sensor, motion model, Metal renderer and the demo overlay verified on the machine. Live desktop capture still needs a Screen Recording grant on that machine. |
| Android | Emulator, 7.6 inch fold-in profile, API 34, in CI | Unit tests and fixtures pass; the fold shader scores 37 to 67 dB against the goldens on the emulator GPU; the splash shader is rendered offscreen and its ring and wet states checked; the wallpaper is applied and driven through a hinge sweep in both modes with timestamped screenshots on every CI run. Not yet run on a physical Galaxy Z Fold 8 or Fold 7. |
| Windows | GitHub Actions runner, WARP software rasteriser | Unit tests, fixtures and the golden render check pass in CI. Not yet run on a physical laptop; a Lenovo Yoga 7i 2-in-1 is the planned test machine. |
Physical Galaxy Z Fold 8 and Windows laptop reports are welcome as issues. Include the device, OS version, what the settings screen or tray menu says about the sensor, and a short recording if you can.
Credits
The lid angle sensor was documented by Sam Henri Gold's LidAngleSensor (Apache 2.0). Lidfold and Mac Duo showed the way on macOS; duo-open and FoldFX on Android. Hingewave is independent work and is not affiliated with Apple, Samsung, Google or Microsoft. iPhone, iPhone Duo and MacBook are trademarks of Apple Inc.
License
MIT. See LICENSE.