OrcaSlicer/docs/printer-agent/camera.md

Camera support

Owns the three camera ownership models and what each one renders through. Defers the Snapmaker filament path to Built-in agents, even though the same subclass owns both.

Camera support has three ownership models. They share the Device panel, but not a common frame or stream interface.

Two render surfaces, never one:

flowchart LR
    BU["Bambu URL provider<br/>LAN or cloud, not from IPrinterAgent"]
    MU["Moonraker webcam discovery<br/>/server/webcams/list stream URL"]
    SU["Snapmaker camera page<br/>local HTML that polls monitor.jpg"]

    BV["wxMediaCtrl2<br/>native Bambu media pipeline"]
    WV["Device-panel wxWebView<br/>stream URL or local polling page"]

    BU --> BV
    MU --> WV
    SU -- overrides normal discovery --> WV

Bambu

Bambu playback uses wxMediaCtrl2 and the native Bambu media pipeline. The URL comes from the Bambu LAN or cloud path, not from IPrinterAgent. A printer agent should not attempt to force a Bambu URL through the Moonraker or WebView path.

Moonraker live view

On connection, the Moonraker agent obtains the first enabled webcam URL from /server/webcams/list. An absolute HTTP URL is used directly. A relative URL is resolved against the printer's host web root, with the Moonraker API port removed. This is necessary because a relative webcam path may exist on the printer's web server but not on the API port.

The connection generation guards the result. A late request must not replace the URL after the user has selected a different printer. Failed discovery clears the URL, which prevents a prior camera from remaining visible on a printer with no camera.

The agent places the discovered URL in its status payload. The Device panel renders it in wxWebView. It reloads only when the URL changes and resets the camera-start timestamp at that point. Reloading every update would loop indefinitely for endpoints that redirect, so an unchanged URL is shown again without calling LoadURL().

The trade-off is intentional: a WebView that loses an unchanged stream does not automatically reload. Camera controls beyond live viewing remain out of scope for Moonraker. Recording, timelapse, settings, and virtual camera are Bambu-oriented features and must not be presented as supported merely because live view works.

Snapmaker polling view

Snapmaker overrides normal webcam discovery. It writes a per-printer local HTML page that polls the printer's monitor.jpg with a cache-busting URL. Each next request starts after the prior image loads or fails, preventing requests from piling up on a slow printer. A raw snapshot URL is not used, because it would display one frozen frame instead of a live-looking view.

The printer must be asked to start its camera capture task. While the camera view is visible, the Device panel requests this at first display and then attempts another request every 300 seconds. Other agents reject the command quietly, so the common timer does not create an error for Bambu or ordinary Moonraker.

The Snapmaker command is sent from a detached thread because the request can block on socket I/O and the printer responds over a different channel. This avoids blocking the UI but leaves a raw-this lifetime risk: the agent can be destroyed while the detached operation still refers to it. Do not extend this path without addressing that ownership boundary.

The wrapper is written below the application cache with a name derived from the printer IP. The source contains no cleanup path for those files, so they can accumulate as different printer IPs are used. This is source-derived and was not reproduced during this rewrite.

Source code proves 300-second renewal attempts only. The long-running behavior of the shipped polling and renewal cycle has not yet been tested. Do not claim that the attempt renews an active capture task or that it prevents camera expiry until hardware verification establishes both.

Maintenance checklist

• Keep the three ownership models separate.
• Preserve host-root resolution for relative Moonraker URLs.
• Keep generation guards and stale-URL clearing on every discovery path.
• Reload WebView content only after a URL change.
• Reset the camera-start timestamp when the camera URL changes.
• Treat Moonraker as live-view-only and Snapmaker lifecycle behavior as not yet verified beyond the observed renewal attempts.