Setup.Spheres were previously coerced to short cylinders (CylHeight=2*r),
which is geometrically wrong: a cylinder has flat caps; a sphere does not.
This ported CSphere::intersects_sphere (0x00537A80) so sphere-typed shadow
entries are tested as spheres — 3-D distance, no height clamping.
Changes:
- ShadowObjectRegistry.cs: added ShadowCollisionType.Sphere (enum value 2).
The BuildFloodSpheres anyCyl dedup at :232 is unaffected: only Cylinder
sets anyCyl=true; Sphere shapes fall through to the BSP-fallback path
(anyCyl=false → included), which is correct.
- ShadowShapeBuilder.cs: FromSetup now emits ShadowCollisionType.Sphere
(CylHeight=0) for Setup.Spheres instead of a short Cylinder.
- CollisionPrimitives.cs: added SweptSphereHitsSphere — quadratic swept
solve ported from ACE Sphere.cs::FindTimeOfCollision, which is a C# port
of retail's CSphere::intersects_sphere @ 0x00537A80. Sign convention
confirmed against the decomp: retail negates the root to produce a
forward t ∈ (0,1].
- TransitionTypes.cs: added Sphere narrow-phase branch between BSP and
Cylinder in FindObjCollisionsInCell; uses 3-D distance for overlap
(not XY-only). Added SphereCollision() method implementing the 3-D
wall-slide response. Updated diagnostic logging at :2734 to cover Sphere.
- Updated ShadowShapeBuilderTests for new Sphere type assertion.
- New SphereIntersectsSphereConformanceTests: 9 geometrically-anchored
cases (head-on, tangent, perpendicular-miss, lateral-near-miss,
sweep-away, beyond-step, degenerate-zero-sweep, already-overlapping,
vertical-sweep).
Retail oracle: CSphere::intersects_sphere @ 0x00537A80 (named-retail);
ACE Sphere.cs::FindTimeOfCollision (C# port, cross-confirmed).
Build: 0 errors, 10 warnings (pre-existing).
Tests: 1576 pass / 0 fail / 2 skip (1578 total).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Adds CollisionPrimitives.cs with C# ports of FUN_005384e0 / FUN_00539500 /
FUN_00539ba0 / FUN_00539110 / FUN_00539060 / FUN_0053a230 / FUN_0053a040 /
FUN_00538eb0 / FUN_00538f50 — covering ray-sphere, sphere-poly contact,
find-time-of-collision, face-normal computation, ray-plane intersection,
walkable checks, edge-normal slide, and sphere landing.
Key findings from cross-referencing with ACE's Polygon.cs:
- The edge-perpendicular formula is cross(N, edge) (normal × edge), matching
the retail param_1[9/10/8] order in the decompiled loops.
- find_time_of_collision uses t = (dot(origin,N)+D) / dot(dir,N); the sign
is negative when approaching from above — contact = origin − dir*t.
- land_on_sphere only succeeds when the sphere centre is within one radius of
the plane (dist < r), which is the "settling onto ground" scenario.
26 new tests green; full suite 367/367 green.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
