The reader opens a roll of a few thousand frames and holds Ctrl+Shift+R while
it is being read — over a reading that takes minutes, that is the one thing
they do. What came back was a reading that started again at the top: every
folder listed a second time, the toolbar counter back at zero, the frames that
were already in the catalogue walked over so that their size and their write
time could say they had not moved.
None of that was in the catalogue, because the catalogue only holds the frames
that were read. What was lost with the page was the reading's position: the
folders the walk had been through, the folders still in its queue, and the
frames it had found and not yet read. The catalogue alone can never answer
where a reading was.
The position is now written to session storage as the reading goes — walked,
pending and the frames in hand — and read back on the way in. Session storage
and not local storage, because a position belongs to the tab: the tab that
reloads carries on from the frame it stopped at, and a tab opened beside it
starts a reading of its own. The key goes when the reading finishes, and goes
with the folder when the folder is removed.
The frames in hand are the part worth spelling out. A frame a lane is in the
middle of, and a frame whose row is in the batch and not yet in the catalogue,
are on neither side of the line the position is written on: the catalogue does
not hold them and the walk will not find them again, so both are written into
the queue and read again. They also were counted when they left the queue, and
the count is written with them — else the reloaded reading would count them a
second time. The counter now carries on from where it was instead of restarting
from zero.
One thing was hidden behind the other: the stand-in folder the check hands the
page had no `getFileHandle` and no `getDirectoryHandle`, so the path that asks
the root for the frames a position names threw and answered nothing — and the
reading then walked the roll from the top, exactly the behaviour the check was
meant to catch. The check's folder answers both now, the way the browser's does.
Verified:
library-check.mjs — 45 steps, all passed, two of them new. The reading is
stopped on the frame it is reading (`check.hold`), the tab is reloaded, and
it comes back at "Scanning 3/3 — 0 new…" — the same line it was stopped at,
not a reading starting over — with the position still holding 4 folders
walked, an empty queue and 3 frames in hand. Listing 3 tiles and letting the
key go, the reading finishes the roll: 3 tiles in the strip, the catalogue
written, the position cleared, and every folder listed once
({"2026":1,"CheckRoll":1,"Empty":1,"04":1}) where a reading that started
over lists each of them twice.
scan-nav-check.mjs, roll-walk-check.mjs — all passed. frontend tsc --noEmit
clean, vite build clean.
ponytail: the position is the tab's, so a reload keeps it and a new tab does
not — the tab that reloaded is the one the reader is looking at, and a second
tab reading the same roll from the top costs a walk and no bytes, because a
frame that has not moved is dropped on its size and its time. The position is
written at the batch beat, so a reload reads at most one batch again, and the
frames in hand are read again on purpose: their rows were never stored.
Co-authored-by: PenguinHarness <noreply@penguin.local>
The walk already turned its back on the folders a camera and an editor leave
behind: a name beginning with `.` or `@` is skipped, which is `.thumbnails`,
`.git`, `.Trash`, and the `@eaDir` a Synology writes beside every frame.
An external volume drags along a second set of names, and none of them begins
with a dot, so every one of them was walked. `$RECYCLE.BIN` and `RECYCLER` are
where Windows parks what the reader deleted — frames among them, at full size,
and every one of them decoded into a thumbnail on the way in. `System Volume
Information` is Windows' own bookkeeping. `#recycle` is the Synology share, and
`lost+found` is the directory a Linux volume keeps for repairs. A frame that
comes back out of a bin is a frame the reader threw away, and the pictures in a
share's recycle folder are pictures someone else deleted; neither belongs in
the catalogue, and both cost the reading the same seconds a real frame does.
The folder also stood in the column as a row of its own.
The rule is now one `SYSTEM_DIR` expression over both sets, matched
case-insensitively — the same volume spells the bin `$RECYCLE.BIN` on one drive
and `$Recycle.Bin` on the next — and the walk asks it before it looks at what
the entry is, so a refused folder is neither read nor named.
Verified:
roll-walk-check.mjs — all passed, with two new assertions: the stand-in roll
now carries `$RECYCLE.BIN`, `$Recycle.Bin`, `RECYCLER`, `System Volume
Information`, `#recycle` and `lost+found`, and every one of them holds a
file named like a frame, so nothing about the files can be what keeps them
out. No frame is read from them, and none of them reaches the column.
library-check.mjs — 43 steps, all passed. scan-nav-check.mjs — all passed.
frontend tsc --noEmit clean.
ponytail: the list is the names the volumes being read actually use, not a
guess at every spelling there is — a box that files its junk under something
else gets a line in that expression, which is the whole of the change. A folder
of the reader's own that happens to be called `#recycle` is skipped too; that
name is worth the trade.
Co-authored-by: PenguinHarness <noreply@penguin.local>
3dtours