llamamod/notes/mod-levels.md

Level projects as mods (mods.levels, category LEVELS)

Every .llamalevel file (format: notes/editor-format.md) in <data>/levels/ is a mod. Code: mods/levels/LevelProjectSource (a ModSource), LevelProjectMod, LevelProjects (folder, importFile for an "Import level…" button), LoadingPicture, EditorCli.

id	level-<file name> (lower case, non-alphanumerics → -)
name / description	level name, description and author from the project
version	first 16 hex digits of the file's SHA-256 (any change of the file rebuilds)
order	60: after Test World (50, chapter 1), before Mirror (75) and the debug view (100), so those also apply to the level
option chapter (new levels only)	TestLevel (world 9) chapter 1..49; default = the project's targetChapter, or the next free one (from 2) if another project already uses it

Apply: the project is loaded against the pristine CD (ctx.originalCd()), built with editor.io.WadBuilder and written to wads/T1L9M0nn.wad (new levels) or wads/<base>.wad (edited originals). New levels also get a loading picture T19<n>.COR (thumbnail if present, level name, "TestLevel – chapter n"). If the target was already changed by an earlier mod (Test World on chapter 1, another level on the same chapter, two edits of one original level), the apply stops with a clear message naming the file and what to do.

World 9: ModManager.world9Fixup now also works when only a chapter other than 1 is provided: the lowest provided chapter fills all missing chapters 1..49 (the map crashes on a missing chapter WAD), loading pictures as before. To play chapter n: unlock it in the save editor (or --unlock <slot> 9 <n> --cursor), then select it on the world-9 map.

CLI (EditorCli): --editor-import, --editor-new, --editor-build, --import-level, see editor-format.md. The registry reads the folder when it is created (restart the app / create a new ModRegistry after importing).

Verified in game (apptest, display :7, Wine 6, 2026-11-06)

• Original imported → project → built (--editor-import t1l1m001, mod level-village): the WAD in cd-active is byte-identical to the CD file; Village 1 loads and plays (intro, Pacha).
• Edited original (level-village-edited: three coins moved, coins, charge boosters and three CheckPointPosts added): loads and plays; the added post stands where placed (3 cells ahead of the start, img/mods/levels_01_village_edit.jpg), the moved coins appear at their new places, added coins are collected (coin HUD). Note: in Village 1 the coins and other objects within ~3 cells of the start are not visible at the start (also in the original), so edits there are hard to see.
• New level from brushes (examples/testwelt.llamalevel → level-testwelt, chapter 2): loads from the world-9 map (slot shows "TestLevel Kapitel 2"), generated loading picture, plaza, gallery objects, walking (img/mods/levels_02_testwelt_chapter2.jpg). Its geometry, objects, waypoints and textures equal the Test World mod's WAD (unit test; only the generated death plane model differs).
• Mesh and texture import (testwelt + an OBJ box with a PNG texture via MTL, a block with an imported PNG texture, chapter 3): both render with their textures, the mesh has collision (img/mods/levels_03_mesh_import.jpg).

Known limits

• Exit doors (LevelDoor) keep their parameters; the test world's door leads to (1,9,1) = chapter 1 (which then is a copy of the lowest provided chapter if no other mod provides it).
• New ModRegistry instances are needed to see newly imported projects.