Device calls no longer block the calling isolate #

pv_request used to answer in-band, so a call sat on the caller's thread until the engine was done — up to ten seconds for open with no panel attached, which froze the UI. It now hands the request over and returns; the answer is posted to the pv_init SendPort as a PvResponse carrying the id its request was sent with, and the controller completes the matching Future.

First published release.

Display #

• PicoView widget mirrors its child subtree to an external SPI LCD driven by ESP32-P4 firmware over a driverless USB vendor-bulk link. The child is laid out at exactly the panel's resolution, so a captured pixel maps 1:1 to a panel pixel.
• Capture is driven off Flutter's frame pipeline rather than a fixed-rate timer, and frames are only sent when the content actually changed — a static screen produces no USB traffic. Cap the rate with PicoView(maxFps: ...).
• A trailing capture guarantees the final resting frame of an animation reaches the panel even when it settles inside a throttle window.
• The mirror keeps running while the app window is hidden or minimized, by driving the frame pipeline manually once the engine stops requesting frames.
• PicoViewController.flushRgba pushes a pre-rendered RGBA8888 frame directly, for producers that bypass the widget capture path (set suspendCapture while they own the panel).

Touch #

• Physical capacitive touches are injected back into the mirrored subtree as synthetic pointer events, so ordinary GestureDetectors and Material widgets respond to the panel.
• Per-event deltas and monotonic timestamps are carried through, so drag and velocity-based recognizers (sliders, flings) behave as they do on-screen.
• Raw events are also exposed on PicoViewController.touches in panel pixel coordinates.

Device #

• open / dispose lifecycle, setBrightness, playHaptic / stopHaptic (DRV2605L ROM waveforms), and otaStart for streaming a signed firmware image, with progress on otaEvents.
• getDeviceInfo() round-trips to the device for its id, serial, firmware version, panel geometry and capabilities.
• linkStates reports connect/disconnect transitions; the engine reconnects on its own.
• Devices carrying a vendor-provisioned identity can be attested — see deviceVerified and attestedDeviceId.

Packaging #

• The Rust engine ships as a prebuilt library for Linux x64/arm64, macOS x64/arm64 and Windows x64. hook/build.dart downloads the release pinned in native/engine.lock, verifies its SHA-256 and links it as a native code asset, so consuming apps need no Rust toolchain.
• The C ABI is frozen at five symbols; everything except the raw-frame hot path travels as protobuf messages, so new engine capabilities arrive as new message variants rather than new symbols.
• A no-op web stub keeps code using package:pico_view compiling for web.