feat(map): browse the prepared Hyrule atlas from 3DS SD storage

README.md

@@ -4,11 +4,22 @@ A map browser for Nintendo 3DS and PSP, built with [PocketJS](https://github.com
 
 The Mac fetches OSM vector tiles, prepares bounded geometry and streams it to the 3DS GPU drawing path. Four real San Francisco tiles used **79.5% fewer terrain bytes** than the previous raw bitmap path; z14 geometry is reused through display z18. Hyrule retains its complete local raster atlas and 2,576 searchable places, with no internet requests while browsing. See [vector architecture, measurements and limits](docs/VECTOR_MAP.md).
 
-<p><img src="docs/images/vector-osm.png" width="320" alt="Actual San Francisco vector data rendered by the compiled dual-screen Pocket Map guest" /> <img src="docs/images/hyrule.png" width="320" alt="Pocket Map displaying the local Hyrule atlas on a compiled dual-screen guest" /> <img src="docs/images/hyrule-search.png" width="320" alt="Local Kakariko search results with the bottom-screen selection touchpad" /></p>
+### San Francisco on the 3DS native renderer
+
+Union Square, the Embarcadero near the Ferry Building, and Golden Gate Park:
+
+![Union Square, San Francisco — Pocket Map's native 3DS build in Azahar](docs/images/sf-union-square-3ds.png)
+![Embarcadero near the Ferry Building, San Francisco — Pocket Map's native 3DS build in Azahar](docs/images/sf-ferry-building-3ds.png)
+![Golden Gate Park, San Francisco — Pocket Map's native 3DS build in Azahar](docs/images/sf-golden-gate-park-3ds.png)
+
+These are **native 3DS screenshots captured in Azahar**, using real OSM data and
+the production app's UI. The 400×240 upper and 320×240 lower framebuffers are
+stacked without scaling. They are emulator captures, not console photographs.
+[Capture method, coordinates and provenance](docs/images/CAPTURES.md).
 
 OSM map data © [OpenStreetMap contributors](https://www.openstreetmap.org/copyright), served as Shortbread vectors by VersaTiles.
 
-These are **compiled guest + Wasm captures**, at the 3DS's 400×240 / 320×240 logical resolutions, not console photographs. Map artwork belongs to Nintendo; the pinned atlas and marker source is [Zelda Dungeon's map repository](https://github.com/zeldadungeon/maps/tree/d32a85656031d861cef38e32eb927a7d08a983a9/public/botw). Downloaded assets and generated databases stay outside Git.
+Map artwork belongs to Nintendo; the pinned atlas and marker source is [Zelda Dungeon's map repository](https://github.com/zeldadungeon/maps/tree/d32a85656031d861cef38e32eb927a7d08a983a9/public/botw). Downloaded assets and generated databases stay outside Git.
 
 ## PSP over USB
 
@@ -72,17 +83,28 @@ queue; it is not a device-render receipt.
 
 The Mac keeps connection management separate from native decoding and network work. If the capability process exits, it is reaped and replaced on reconnect. Socket backpressure pauses traffic; cancelling a sent device request retains its wire credit until a reply or disconnection.
 
-Typing, dragging, inertia and zoom transitions update locally. Missing tiles show a fallback; an already loaded previous zoom level stays visible during replacement. A disconnected Mac leaves resident tiles navigable. Search, new tiles and uncached labels require the Mac, including in Hyrule mode. Offline here means independent of internet map services, not independent of the paired Mac.
+Typing, dragging, inertia and zoom transitions update locally. Missing tiles show a fallback; an already loaded previous zoom level stays visible during replacement. The optional [Hyrule SD pack](docs/SD_MAP.md) lets the 3DS open and load the entire terrain atlas without a Mac. Search, saved places, OSM and dynamic labels still use the paired host. Without the pack, a disconnected Mac leaves only resident tiles navigable.
+
+## Hyrule on the 3DS SD card
+
+After preparing the Mac atlas, run `bun run prepare:sd` and
+`bun run deploy:sd <3ds-ip>` to install a **354 MiB** prepared texture pack.
+The console reads and inflates individual records on a native worker; terrain
+misses no longer require Wi-Fi. In one physical 3DS comparison, mean time to
+ready terrain across four views fell from **1,178 ms over Wi-Fi to 293 ms from
+SD**. This does not establish sustained 60 FPS. See [installation, storage costs,
+measurements and limits](docs/SD_MAP.md).
 
 ## Complete local Hyrule atlas
 
 `bun run prepare:hyrule` sparsely checks out a pinned Zelda Dungeon revision:
 1,365 JPEG source tiles across six levels, about 49 MB. It rebakes the full
 24,000px square source into **21,845 RGB565 textures across levels 0–7**, using
 256px texture envelopes. Original source detail is preserved by subdividing
-the 750px tiles; the top level is a 32,768px grid. Deflate compression is used
-only for Mac storage. The 3DS receives raw pixels and performs no JPEG or
-Deflate decoding.
+the 750px tiles; the top level is a 32,768px grid. In the desktop streaming path,
+Deflate is used for Mac storage and the 3DS receives raw pixels. With the optional
+SD pack, the Mac prepares PICA texture layout and the native SD worker inflates
+individual records. The 3DS performs no JPEG decoding.
 
 The completed `.local/hyrule/atlas.sqlite` is about **592 MB** and includes an
 FTS5 index of regions, landmarks, towers, shrines, villages, Korok seeds and
@@ -176,7 +198,7 @@ const view = createResourceView(tiles, { demand: visibleTileDemand });
 // <ResourceMesh state={() => view.state(tile)} fallback={() => <TileSkeleton />} />
 ```
 
-Hyrule declares `createOffloadImageCollection` and renders `ResourceImage`.
+Hyrule declares `createPackedImageCollection` with a desktop fallback and renders `ResourceImage`.
 Rendering starts no IO. The native worker owns reception; the scheduler admits
 one materialization per frame; the collection returns staging and eventually
 frees its native handles.