From 1454eab75aa711962205d248686c87f27d41ff20 Mon Sep 17 00:00:00 2001
From: Erik <erik.nihlen@gmail.com>
Date: Sun, 24 May 2026 15:14:20 +0200
Subject: [PATCH] feat(phys): ShadowEntry adds LocalPosition + LocalRotation

Local-to-entity transform fields, default-valued so existing single-shape
callers keep working unchanged. RegisterMultiPart (next commit) populates
them per part so UpdatePosition can rebuild the entry's world Position +
Rotation when the entity moves.

All 24 existing ShadowObjectRegistry tests pass (including the 2 new
slice 1 tests from b49ed90).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
---
 src/AcDream.Core/Physics/ShadowObjectRegistry.cs | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/AcDream.Core/Physics/ShadowObjectRegistry.cs b/src/AcDream.Core/Physics/ShadowObjectRegistry.cs
index 8a4518a..e0425d8 100644
--- a/src/AcDream.Core/Physics/ShadowObjectRegistry.cs
+++ b/src/AcDream.Core/Physics/ShadowObjectRegistry.cs
@@ -431,4 +431,11 @@ public readonly record struct ShadowEntry(
     /// from <c>PWD._bitfield</c> at <c>CreateObject</c> time via
     /// <see cref="EntityCollisionFlagsExt.FromPwdBitfield(uint)"/>.
     /// </summary>
-    EntityCollisionFlags Flags = EntityCollisionFlags.None);
+    EntityCollisionFlags Flags = EntityCollisionFlags.None,
+    // A6.P4 door fix (2026-05-24): local-to-entity transform for multi-part
+    // entities. ShadowObjectRegistry.UpdatePosition uses these to rebuild
+    // Position/Rotation when the entity moves. Single-shape callers leave
+    // these at default (zero offset, identity rotation) — equivalent to
+    // the shape sitting at the entity's origin.
+    Vector3 LocalPosition = default,
+    Quaternion LocalRotation = default);