vnidrop/packaging/apple/studio/README.md

App Store screenshot studio

Code-driven, fully local App Store screenshots — composed natively with SwiftUI + ImageRenderer and SceneKit (no Typst, no ImageMagick). Each marketing screen is a SwiftUI view (gradient + 3D device + captions + generated artwork) rendered off-screen to an exact-size PNG. Captions come from strings.json (9 locales); the app screenshots on the device screens are captured from the real app.

Requirements

• Xcode / Swift toolchain (macOS 26+). That's it.

Run

swift run studio                      # all locales × screens -> generated/<Language>/
swift run studio --publish            # -> ../<Language>/ (ships to App Store)
LOCALES="fr de" SCREENS="share-securely" swift run studio        # subset
PLATFORM=ipad swift run studio        # iPad set -> generated/<Language>/iPad/
PLATFORM=mac swift run studio         # Mac set  -> generated/<Language>/Mac/

PLATFORM must match between capture.sh and swift run studio (they read the same generated/shots/<platform>/ tree). Run from this directory (it reads strings.json and assets/ relative to cwd).

Full pipeline

./capture.sh        # real localized app screens -> generated/shots/<platform>/<locale>/
swift run studio    # composite everything -> generated/<Language>/[iPad/]
./generate.sh       # capture + composite in one shot (forwards PLATFORM / --publish)

capture.sh drives the app into each screen via the DEBUG -VniScreenshot launch argument (see apple/VniDrop/App/ScreenshotSupport.swift), once per locale via -AppleLanguages, in dark mode. Screenshots are transient (git-ignored, regenerated per run) — during layout iteration, capture once then re-run swift run studio on its own.

• iPhone / iPad run in the simulator (9:41 status-bar override) via simctl.
• Mac has no simulator: capture.sh builds the native app, launches the binary directly, sizes its window with osascript, and grabs it with screencapture. Grant the terminal Accessibility + Screen Recording permission the first time.

Platforms

PLATFORM=iphone (default), ipad, or mac. Each Platform (Sources/studio/Platform.swift) carries its canvas size, capture target, output subfolder, and a DeviceModel — the .usdz, its screen material, the orientation fix (yaw so the screen faces the camera), optional front-glass mesh to hide, whether to tint the body graphite, a fillFraction (how much of the frame the device fills; lower for wide 3/4 poses that would otherwise clip), and a screenPad (black margin baked around the shot so the window clears the display's rounded corners). Adding a device is a new DeviceModel + Platform case + a layout set. (The studio is Apple-only today; the same SwiftUI/SceneKit approach is intended to extend to Android and Windows later.)

Device rendering

SceneKitDeviceRenderer textures the captured screenshot onto the model's screen mesh and renders it off-screen. Curvature, bezel and body are the model's real geometry; poses (pitch/yaw/roll) and a studio environment (IBL + bloom) are applied in the scene. It auto-generates planar [0,1] UVs for screen meshes that ship without them, and mattes the shot onto a slightly larger black canvas (screenPad) so the display edge stays black instead of smearing the capture's corner pixels.

Assets (assets/)

• iphone-17-pro-max.usdz, ipad-pro.usdz, macbook-air.usdz — the 3D devices (committed; CC BY 4.0, see ATTRIBUTION.md).
• globe.png — for the send-anywhere hero (committed).
• generated/shots/<platform>/<locale>/*.png — captured app screens (transient).

Layout & tuning

• Sources/studio/ScreenSpec.swift — per-platform layouts (iphone / ipad / mac): gradient, device pose/position/size, globe + route (send-anywhere), the encryption flow (stay-private: beams → lock → stream + banners), caption placement. beams and stream take a horizontal flag for side-by-side devices (used by Mac stay-private).
• Sources/studio/ScreenFrame.swift — the composition (layer order, caption fitting, generated artwork).

Screens

share-securely, choose-receivers, send-anywhere (globe + Paris→LA route arc, reuses the share screenshot), stay-private (encryption beams → padlock → binary protection stream, with localized CHIFFREMENT/PROTECTION banners; two stacked phones on iPhone/iPad, two side-by-side laptops with a horizontal flow on Mac).