@build-qube/papyra-tauri

Tauri engines for papyra's viewer and file preview: PDFs, TIFFs, spreadsheets, and Word and PowerPoint are parsed and rendered by papyra in the app's host process, through the tauri-plugin-papyra crate. TauriEngine is the PDF engine; openTiff and openWorkbook mirror papyra's own and resolve to its classes; and TauriOfficeEngine stands in for papyra's officeEngine.

A Tauri app's WebView is never cross-origin isolated on Android or iOS, so papyra's wasm build cannot run there. This engine does not need it: the Rust side renders on the device's real cores, and the WebView only paints.

Installing it, wiring tauri-plugin-papyra into the app, and keeping papyra's wasm out of the bundle are in the Tauri guide.

Pages and lifetimes

Pages travel over a papyra:// protocol, as PNG by default. new TauriEngine({ format: 'rgba' }) sends raw pixels instead: no encode or decode, four times the bytes. Which is faster depends on the device.

Documents stay in the host until closed — TIFFs and workbooks too, through their close(). The viewer's store and file preview close what they open; if you call the engine yourself, await engine.close(doc) — it rejects if the host could not release the document. When a WebView loads a page — a reload, HMR, the app restarting its UI — the host drops every document that WebView had open, since nothing on the new page could close them.