WDT format

The WDT map description — one per map, saying exactly which of the 64 × 64 terrain tiles exist (or which single global WMO an object-only map shows), and carrying the map-wide satellite files later expansions added. WDT is the compound user-facing class (the main .wdt file plus its era's _occ/_lgt/_fogs/_mpv satellites, baked into one object); each expansion has a concrete subclass (WDTWod, WDTShadowlandsToDragonflight, …) exposing that version's layout.

Pages:

• WDT entity — the user-facing compound WDT (the main file with every satellite baked in), read/written through the filesystem gateway.
• WDT main file — the main file: every field with the expansion range it is available in (generated from the sources, so the ranges never drift) and its chunk FourCC.
• Satellites — the _occ occlusion, _lgt lights, _fogs volumetric-fog and _mpv particulate-volume files, each field with its FourCC and expansion badges.
• Chunks — the wire structs used across all five files.

Version-agnostic unions

Each family exposes an Any… type alias — the union of its per-version classes (a single-range family's alias is its one class), bound on its module and importable:

from wowlib.formats.wdt import AnyWDT

def process(wdt: AnyWDT) -> None:
    ...

wdt = WDT.for_version(pick_expansion())     # statically typed as AnyWDT

Alias	Module	Union of
AnyWDT	wowlib.formats.wdt	every WDT⟨version⟩
AnyWDTRoot	wowlib.formats.wdt.root	every WDTRoot⟨version⟩
AnyWDTHeader	wowlib.formats.wdt.root.chunks	every WDTHeader⟨version⟩
AnyWDTOcclusion	wowlib.formats.wdt.occlusion	the one WDTOcclusionWodPlus
AnyWDTLights	wowlib.formats.wdt.lights	every WDTLights⟨version⟩
AnyWDTFogs	wowlib.formats.wdt.fogs	every WDTFogs⟨version⟩
AnyWDTParticulates	wowlib.formats.wdt.mpv	the one WDTParticulatesBfaPlus

See the guide's Reading a map (WDT & WDL) for a worked example.