LegacyWeaveLoader/docs/INTERNALS.md

Internals

This file covers how Weave Loader works under the hood.

Symbol resolution

The runtime reads the game's PDB file and resolves function addresses by mangled C++ names. Resolved RVAs are added to the module base to build callable function pointers.

We use raw_pdb to parse PDBs without the DIA SDK.

Texture atlas merging

1. Mod textures are found under mods/*/assets/<namespace>/textures/.
2. The vanilla terrain.png and items.png are loaded.
3. Empty cells are detected and mod textures are placed into them.
4. The merged atlas is written to mods/ModLoader/generated/.
5. File open hooks redirect the game to the merged atlases during init.

Model asset overlay

When the game requests assets/<namespace>/models/..., WeaveLoader redirects to the mod's matching file under mods/*/assets/<namespace>/models/.

String table injection

The runtime locates the game's string table and appends mod strings directly. This avoids relying on inlined string lookup calls.

Crash handler

A vectored exception handler writes crash reports with register dumps, stack traces, and loaded modules. It also skips __debugbreak() asserts so the game can continue running.

ID ranges

Type	Numeric Range	Notes
Blocks (Tiles)	174 -- 255	82 slots; maps to TileItem in Item::items[]
Items	3000 -- 31999	Constructor param = numericId - 256
Entities	1000 -- 9999	Reserved for mod entities