7DTD 3.0.0 API Changes (Mod Migration)

Breaking C# API changes observed when migrating mods from 7DTD 2.x to 3.0.0. A mod DLL compiled against 2.x loads under 3.0.0 but throws MethodAccessException / Method not found at runtime for any removed overload. Recompile against the 3.0.0 Assembly-CSharp.dll to surface these as compile errors, then fix per below.

Symptom: silent feature break, Method not found in log

A 2.x DLL that calls a now-removed overload fails only when that code path runs. If the call is inside a try/catch (e.g. an input listener's Update), you'll just see a warning like:

WRN [zPhone] Listener update error: Method not found: void .GUIWindowManager.Open(string,bool,bool,bool)

The 4-arg Open doesn't exist in source — the 2.x compiler baked optional-parameter defaults into the call site, so a 2-arg source call (Open("x", true)) compiled to a 4-arg IL call. When 3.0.0 changes the optional params, the baked call no longer resolves. Recompiling re-binds it to the current overload.

World — clrIdx (cluster index) first parameter removed

3.0.0 dropped the leading int _clrIdx argument from many World block/tile methods (continues the same cleanup as the ExplosionServer clrIdx removal). Block position now goes through BlockValueRef, which has an implicit conversion from Vector3i (and a new BlockValueRef(Vector3i) ctor).

2.x call	3.0.0 call
world.GetTileEntity(0, pos)	world.GetTileEntity(pos) — GetTileEntity(Vector3i) or (BlockValueRef)
world.SetBlockRPC(0, pos, bv)	world.SetBlockRPC(new BlockValueRef(pos), bv) — SetBlockRPC(BlockValueRef, BlockValue)

World.ChunkClusters collection removed → World.ChunkCache

The indexed world.ChunkClusters[i] list is gone. There's now a single primary public ChunkCluster ChunkCache field. Replace the iterate-all-clusters pattern:

// 2.x
for (int i = 0; i < world.ChunkClusters.Count; i++) {
    var ebcd = world.ChunkClusters[i].GetBlockEntity(pos);
    ...
}
// 3.0.0
var ebcd = world.ChunkCache?.GetBlockEntity(pos);   // ChunkCluster.GetBlockEntity(Vector3i)

XUiController.RefreshBindings(bool) → RefreshBindings()

The bool overload (force/release) was removed; only the no-arg RefreshBindings() remains. Drop the argument at every call site.

GUIWindowManager.Open overloads

Current overloads (no 4-arg form):

Open(string _windowName, bool _bModal)
Open(string _windowName, bool _bModal, bool _bIsNotEscClosable)
Open(GUIWindow _w, bool _bModal)
Open(GUIWindow _w, bool _bModal, bool _bIsNotEscClosable)

Source like windowManager.Open("zPhoneHome", true) is still correct — it binds to the 2-arg overload once recompiled.

XUi: vanilla folder split — mods must move Config/XUi/ → Config/XUi_InGame/

This is the big one and easy to miss. 2.x loaded a single Data/Config/XUi/ folder. 3.0.0 split vanilla XUi into three folders: XUi_Common, XUi_InGame, XUi_Menu (confirmed as metadata strings in Assembly-CSharp.dll; the old Config/XUi/ is gone).

7DTD's modlet patch system applies a mod file by mirroring the vanilla file's exact relative path. So a mod that shipped Config/XUi/windows.xml + Config/XUi/xui.xml patched the 2.x vanilla Config/XUi/*. In 3.0.0 there is no Config/XUi/ to mirror, so those mod files patch nothing — and there's no error. xui reload even logs Parsing all window groups completed because it parsed the (now-orphan) document; the window group still never reaches the in-game GUIWindowManager. Net symptom: Window "<name>" unknown! at Open() time even though the files look loaded.

Fix — relocate the mod's in-game UI files to mirror the new path:

Config/XUi/windows.xml  ->  Config/XUi_InGame/windows.xml
Config/XUi/xui.xml      ->  Config/XUi_InGame/xui.xml

(In-game HUD/gameplay windows → XUi_InGame; main-menu UI → XUi_Menu; shared styles/controls → XUi_Common.) Vanilla roots are unchanged: XUi_InGame/windows.xml root is <windows>, XUi_InGame/xui.xml root is <xui> — so xpath="/windows" and xpath="/xui" appends still work.

<ruleset> wrapper also removed from xui.xml

2.x wrapped window-group registration in <xui><ruleset name="default">.... 3.0.0 removed the <ruleset> element — <window_group> nodes are now direct children of the root <xui>. Any modlet that registered a custom window group with:

<append xpath="/xui/ruleset[@name='default']">   <!-- 2.x: no longer matches anything -->

silently no-ops in 3.0.0 (the xpath matches nothing, no error), so the window group never registers. Symptom at runtime — opening the window logs:

WRN GUIWindowManager.Open: Window "<name>" unknown!

Fix: append directly to /xui:

<append xpath="/xui">
    <window_group name="..." controller="...">
        <window name="..." />
    </window_group>
</append>

windows.xml is unchanged — window definitions still append to /windows. Note the split: vanilla XUi now lives under Data/Config/XUi_InGame/, XUi_Menu/, XUi_Common/ (the old single Data/Config/XUi/ folder is gone), but mods still ship their own Config/XUi/ folder.

This is an XUi-only change → hot-reloadable (xui reload), no DLL rebuild or game restart.

Localization: Config/Localization.txt → Config/Localization.csv

3.0.0 renamed the per-mod localization file. Localization.LoadPatchDictionaries hardcodes Localization.csv; a mod still shipping Localization.txt gets no error, no log line — item/entity tooltips just show raw keys (vehicleFooPlaceable). Rename (or ship both for 2.x compat) and restart the game — mod localization is only loaded at startup (ModManager.LoadLocalizations bails when _isLoadingInGame). Column mapping is by header name, so old headers without 3.0.0's KeepLoaded column still work. Details in Localization.

Block activation methods also lost _cIdx (and the _interaction string)

The Block activation surface dropped the cluster-index parameter in 3.0.0 (same cleanup as the World methods above). Current signatures (reflection-verified, Elevator mod 2026-07):

bool  OnBlockActivated(WorldBase _world, Vector3i _blockPos, BlockValue _blockValue, EntityPlayerLocal _player)
bool  OnBlockActivated(string _commandName, WorldBase _world, Vector3i _blockPos, BlockValue _blockValue, EntityPlayerLocal _player)
bool  HasBlockActivationCommands(WorldBase _world, BlockValue _blockValue, Vector3i _blockPos, EntityAlive _entityFocusing)
BlockActivationCommand[] GetBlockActivationCommands(WorldBase _world, BlockValue _blockValue, Vector3i _blockPos, EntityAlive _entityFocusing)
string GetActivationText(WorldBase _world, BlockValue _blockValue, Vector3i _blockPos, EntityAlive _entityFocusing)

Note the old 2.x OnBlockActivated(string _interaction, WorldBase, int _cIdx, ...) form (still visible in older mods like SentryLight) no longer overrides anything — copying signatures from an un-migrated sibling mod produces methods that silently never get called. Reflect on the current assembly instead.

Block lifecycle signatures (3.0, reflection-verified)

OnBlockAdded gained a trailing PlatformUserIdentifierAbs; the other two are unchanged (verified against the 3.0 assembly, Elevator mod 2026-07):

void OnBlockAdded(WorldBase _world, Chunk _chunk, Vector3i _blockPos, BlockValue _blockValue, PlatformUserIdentifierAbs _addedByPlayer)
void OnBlockRemoved(WorldBase _world, Chunk _chunk, Vector3i _blockPos, BlockValue _blockValue)
void OnBlockUnloaded(WorldBase _world, Vector3i _blockPos, BlockValue _blockValue)

Gotchas when overriding OnBlockRemoved to clean up per-block mod data:

• It fires for every air-set, including your own SetBlocksRPC batches. A mod that moves blocks (like the Elevator car) must guard with "is this position part of my own move?" or it deletes its data mid-move.
• Check _blockValue.ischild and only act on the master of a multiblock.
• Chunk unload is OnBlockUnloaded, not OnBlockRemoved — unload must NOT drop persistent data.

GameManager.ShowTooltip is static now

GameManager.Instance.ShowTooltip(...) → CS0176. Call it as GameManager.ShowTooltip(EntityPlayerLocal _player, string _text, bool _showImmediately, bool _pinTooltip, float _timeout).

Chunk.RemoveTileEntityAt is generic

chunk.RemoveTileEntityAt(world, localPos) no longer infers — use chunk.RemoveTileEntityAt<TileEntity>(world, localPos).

ModEvents handlers take typed ref-struct data

Every ModEvents event is a ModEvent<TData> whose handler signature is void Handler(ref ModEvents.S<Name>Data _data):

ModEvents.GameStartDone.RegisterHandler(OnGameStartDone);
static void OnGameStartDone(ref ModEvents.SGameStartDoneData _data) { ... }

Also new and very useful: ModEvents.UnityUpdate fires every Unity frame — per-frame input polling / timers from a plain static class, no MonoBehaviour or Harmony patch needed. Guard on GameManager.Instance?.World != null since it also fires in the main menu.

Migration checklist

1. Point the csproj Assembly-CSharp reference at the 3.0.0 7DaysToDie_Data\Managed\.
2. dotnet build and fix every error (the ones above are the common ones).
3. DLL change → full deploy + game restart (not xui reload) to take effect.
4. Quick way to discover a new signature without a decompiler — reflect on the shipped DLL: [Reflection.Assembly]::LoadFrom("...\Assembly-CSharp.dll").GetType("World").GetMethods() | ? Name -eq 'GetTileEntity'