The thumbnail cache wrote .jpg files into the library's thumbs folder, which is usually inside
Pictures: photo galleries listed every thumbnail as a photo (issues #610, #1066), and every read
brought the file's date forward, so each launch made them all look new.
- Cache files are named <32 hex>.lcthumb (JPEG data as before). A .jpg of before is taken over
under the new name when it is asked for; the rest when the cache is tidied, which the engine does
once per cache folder, on a thread of its own with a row in the activity stack that shows its
progress and can stop it. Nothing is rendered again.
- Reading writes nothing: what was read is remembered for the session (a full cache lets it go
last), and only a file that went unused for a week has its date brought forward.
- A folder that holds nothing but the cache gets a CACHEDIR.TAG, when the cache makes it and when
it is tidied; one that also holds somebody's files is not tagged (issue #98).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
An unedited raw's face tile is cut from its largest embedded preview, read
the planned way (header and JPEG, never the sensor data), when the preview
holds at least 3/4 of the tile's pixels across the face; otherwise, and for
edited photos and other files, it is developed as before. Tiles keep going
to the memory + on-disk thumbnail cache, now at 16 px size steps so the
thumbnail slider reuses them. The planned preview path carries an Adobe RGB
preview colour space and applies it instead of declining to the whole-file
read (Sony alpha 1 previews).
