* The level.FileSystem type has updated to support ZIP files too.
* Legacy levels loaded from gz/json have their old FileSystem as a
simple map[filename]data and this parses from JSON OK.
* On save to zip, the legacy loaded file data gets exported to ZIP.
* Going forward: newly added or deleted files during runtime are kept in
the legacy file map until the next save when the filemap is again
flushed out to ZIP.
* For regular read-access, the FileSystem reads from the ZIP file if the
data is not in the hot map (legacy file or recently modified
attachment).
* Bugfix: be sure to Inflate() the Level/Doodad after loading from
zipfile - it used to be that directly after a save, trying to play the
level failed because the Level.Actors struct was missing their IDs,
and similarly recently written chunks would error out (become black
voids) on levels/doodads so we Inflate() both after save/replacing
their zip handle.
Especially to further optimize memory for large levels, Levels and
Doodads can now read and write to a ZIP file format on disk with
chunks in external files within the zip.
Existing doodads and levels can still load as normal, and will be
converted into ZIP files on the next save:
* The Chunker.ChunkMap which used to hold ALL chunks in the main json/gz
file, now becomes the cache of "hot chunks" loaded from ZIP. If there is
a ZIP file, chunks not accessed recently are flushed from the ChunkMap
to save on memory.
* During save, the ChunkMap is flushed to ZIP along with any non-loaded
chunks from a previous zipfile. So legacy levels "just work" when
saving, and levels loaded FROM Zip will manage their ChunkMap hot
memory more carefully.
Memory savings observed on "Azulian Tag - Forest.level":
* Before: 1716 MB was loaded from the old level format into RAM along
with a slow load screen.
* After: only 243 MB memory was used by the game and it loaded with
a VERY FAST load screen.
Updates to the F3 Debug Overlay:
* "Chunks: 20 in 45 out 20 cached" shows the count of chunks inside the
viewport (having bitmaps and textures loaded) vs. chunks outside which
have their textures freed (but data kept), and the number of chunks
currently hot cached in the ChunkMap.
The `doodad` tool has new commands to "touch" your existing levels
and doodads, to upgrade them to the new format (or you can simply
open and re-save them in-game):
doodad edit-level --touch ./example.level
doodad edit-doodad --touch ./example.doodad
The output from that and `doodad show` should say "File format: zipfile"
in the headers section.
To do:
* File attachments should also go in as ZIP files, e.g. wallpapers
