The BSP collision detection runs in object-local space, but the
collision response (normals, push offsets) was being applied directly
to world-space SpherePath without rotating back to world space. For
rotated objects (trees, rocks, buildings), this caused the push
direction to be wrong — pushing the player sideways or into the
object instead of away from it.
Added localToWorld quaternion parameter to FindCollisions and all
helper methods (StepSphereDown, CollideWithPt, NegPolyHitDispatch).
All normals and offsets are now transformed via
Vector3.Transform(v, localToWorld) before being applied to SpherePath,
matching ACE's path.LocalSpacePos.LocalToGlobalVec() pattern.
Indoor cell collision uses Quaternion.Identity (cell-local = world).
Object collision passes obj.Rotation.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Replace the patched collision system (~60-70% retail) with a faithful
port of ACE's BSPTree/BSPNode/BSPLeaf/Polygon collision pipeline.
BSPQuery.cs completely rewritten (1808 lines):
- Polygon-level: polygon_hits_sphere_precise (retail two-loop test),
pos_hits_sphere, hits_sphere, walkable_hits_sphere, check_walkable,
adjust_sphere_to_plane, find_crossed_edge, adjust_to_placement_poly
- BSP traversal: sphere_intersects_poly, find_walkable, hits_walkable,
sphere_intersects_solid, sphere_intersects_solid_poly
- BSP tree-level: find_collisions (6-path dispatcher), step_sphere_up,
step_sphere_down, slide_sphere, collide_with_pt, adjust_to_plane,
placement_insert
PhysicsDataCache.cs: Added ResolvedPolygon type with pre-computed
vertex positions and face planes (matching ACE's Polygon constructor
which calls make_plane() at load time). Populated at cache time to
avoid per-collision-test vertex lookups.
TransitionTypes.cs: FindObjCollisions rewritten to use the retail
per-object FindCollisions 6-path dispatcher instead of the old
"find earliest t, then apply custom response" approach. BSP objects
now go through the same collision paths as indoor cell BSP.
The previous approach was explicitly rejected by the user after ~10
iterations of patches. This port follows the CLAUDE.md mandatory
workflow: decompile first → cross-reference ACE → port faithfully.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Indoor CellStruct PhysicsBSP collision for room walls/ceilings.
Dual sphere (body+head) from Setup dimensions.
StepUp attempts before sliding when hitting low obstacles.
FindTimeOfCollision for exact parametric BSP contact time.
Full 6-path BSP dispatcher wired into FindEnvCollisions.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Restructure FindObjCollisions to compute collision ALONG the movement
path instead of at the final position:
BSP: movement-aware SphereIntersectsPoly with front-face culling
(dot(movement, normal) < 0). Only detects faces the sphere is
approaching, matching retail Polygon.pos_hits_sphere.
Cylinder: quadratic ray-cylinder intersection computes parametric
contact time t. If t < 1.0, sphere is rewound to the contact point.
Both: find the EARLIEST collision (minimum t), rewind sphere to
contact point + small epsilon along normal, then SlideSphere.
This prevents the "walking into walls" penetration (BUG-005).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Replace simplified BSP overlap test with retail-faithful 6-path
collision dispatcher. Sphere-intersects-poly now uses movement
vector for front-face culling (prevents wall penetration).
All paths: placement/ethereal, checkWalkable, stepDown, collide,
contact+onWalkable, and default (not in contact).
Ported from ACE BSPTree.cs/BSPNode.cs/BSPLeaf.cs/Polygon.cs,
cross-referenced against decompiled chunk_00530000.c.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Load PhysicsBSP and PhysicsPolygons from GfxObj dats during streaming.
BSPQuery.SphereIntersectsPoly traverses the tree for collision detection.
Ported from decompiled FUN_00539270, cross-ref ACE BSPNode.sphere_intersects_poly.
- PhysicsDataCache: thread-safe ConcurrentDictionary-backed cache of GfxObjPhysics
(BSP tree + polygon dict + vertex array) and SetupPhysics (capsule dimensions).
CacheGfxObj/CacheSetup are idempotent — safe to call at every dat load site.
- BSPQuery.SphereIntersectsPoly: recursive BSP descent with bounding-sphere broad
phase, leaf polygon test via existing CollisionPrimitives.SphereIntersectsPoly
(FUN_00539500), and splitting-plane classification for internal nodes.
- GameWindow: _physicsDataCache populated at all GfxObj/Setup dat load sites
(streaming worker path, live-spawn path, ApplyLoadedTerrain render-thread path).
- 6 new unit tests covering null node, bounding-sphere miss, leaf hit, no-contact,
internal node recursion, and empty cache behaviour. All 447 tests green.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
