Module camera_preview 

<CameraPreview /> — Leptos canvas painted by raw BGRA frames pulled from the CameraFrameSlot (M-PIX.8 of M-RECORD-EXPORT-REAL-PIXELS).

Owns the RecorderPreviewState enum that drives the four UX states (Initialising / AwaitingPermission / PermissionDenied / Live), and a <canvas> element painted at 15 fps by an setInterval worker that polls the latest_camera_frame_bgra Tauri command (raw ArrayBuffer over tauri::ipc::Response — zero JSON overhead).

`CanvasRenderingContext2D::putImageData` expects RGBA in linear
byte order. The capture pipeline emits BGRA (the macOS /
GStreamer / SCK default for screen + camera). We swap the R/B
channels in-place in JS before constructing the `ImageData`.

M-PIX.8 paints the raw rectangular BGRA frame into the canvas
and uses `border-radius: 50%` to render it as a circle. The
wisp-baked mask (described in earlier comments) lives in the
ENCODER side: `RecordingScene` masks the cam sprite into a
circle in the .mp4 output. The UI preview uses CSS so we
don't need a separate wisp pipeline running in the webview
just for the preview.

Structs

CameraPreviewProps

Props for the CameraPreview component.

Enums

RecorderPreviewState

Four-state UX machine for the camera preview surface (M-CAM.3 / AUT-257).

Constants

CANVAS_DOM_ID

Stable DOM id for the <canvas> element. M-CAM.3’s Rust-side pipeline finds the canvas by document.getElementById(...) and putImageDatas frames into its 2D context.

PREVIEW_CANVAS_BYTES

Bytes per frame (BGRA × width × height).

PREVIEW_CANVAS_HEIGHT

Frame height (square: matches the preview pipeline).

PREVIEW_CANVAS_WIDTH

Frame width the camera preview canvas paints at — must match the capture size (screen_app::preview::pipeline::PREVIEW_WIDTH, 720 since M-QUAL.3) so the polled BGRA bytes fit the canvas pixel-for-pixel (putImageData does not scale). The two crates can’t share a constant (native vs wasm), so keep them in lockstep.

PREVIEW_POLL_MS

15 fps preview poll interval in milliseconds. Sufficient for a “see your face” UX; IPC traffic ~31 MB/s at 720×720.

Functions

CameraPreview

<CameraPreview /> — the recorder surface’s webcam preview.

install_camera_frame_poll 🔒

paint_one_frame 🔒