When the server broadcasts a mid-run UpdateMotion with a different
ForwardSpeed (e.g. the player's RunRate changes due to stamina / skill
update), acdream must NOT restart the cycle — that would reset the
footstep cursor and look like a visible twitch. Retail handles this via
Sequence.multiply_cyclic_animation_framerate (ACE
references/ACE/Source/ACE.Server/Physics/Animation/Sequence.cs L277-L287),
which walks the cyclic tail of the queue and scales each node's
framerate by newSpeed / oldSpeed. MotionTable.change_cycle_speed
(MotionTable.cs L372-L379) is the caller from the same-motion path in
GetObjectSequence (L132-L139).
This commit:
1. Adds AnimNode.MultiplyFramerate(factor) — scales a single node's
framerate. Retail also swapped StartFrame↔EndFrame for negative
factors; acdream keeps StartFrame ≤ EndFrame as an invariant and
encodes direction via Framerate sign (see existing comment in
LoadAnimNode), so we only scale. Valid because callers only ever
pass positive factors from UpdateMotion ForwardSpeed.
2. Adds AnimationSequencer.MultiplyCyclicFramerate(factor) — walks
_firstCyclic through the tail and calls node.MultiplyFramerate(factor).
Also scales each node's Velocity and Omega by the same factor so
CurrentVelocity / CurrentOmega stay aligned with playback — matches
ACE's subtract_motion + combine_motion pair in change_cycle_speed.
3. Adds AnimationSequencer.CurrentSpeedMod public property — starts at
1.0, updated by SetCycle on both restart and mid-cycle rescale.
4. Adds a speed-change fast-path to SetCycle: when the (style, motion)
pair matches the current cycle and signs agree,
MultiplyCyclicFramerate(newSpeed/oldSpeed) is called instead of
rebuilding the queue — the cursor stays where it is and the animation
continues at the new rate.
5. Wires InterpretedMotionState.ForwardSpeed from UpdateMotion through
to SetCycle in OnLiveMotionUpdated. ACE omits the ForwardSpeed flag
when speed == 1.0 (InterpretedMotionState.cs:101-103), so we default
missing/zero values to 1.0.
Tests: 4 new sequencer tests covering MultiplyCyclicFramerate,
cursor preservation across speed changes, the same-motion-different-speed
fast-path, and the same-motion-same-speed no-op guard. 632 tests green
(was 628).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Adds IAnimationHookSink + AnimationHookRouter for fan-out of animation
hooks to downstream subsystems (audio, particles, combat, renderer
mutators). GameWindow.TickAnimations now drains ConsumePendingHooks
every tick and broadcasts each hook via the router with the entity's
world position pre-computed.
The router is a composite sink: register N sinks once at startup, each
sees every hook. Registration is idempotent, unregister works, and a
throwing sink no longer poisons dispatch (each OnHook call is wrapped in
try/catch so one bad subsystem can't halt the whole animation tick).
A NullAnimationHookSink is provided for headless tests / offline mode.
6 router tests verify: single/multi sink fan-out, idempotent register,
unregister, throwing-sink isolation, null-sink no-op.
Total: 376 Core tests + 109 Core.Net = 485 (up from 479).
This closes Phase E.1 plumbing; E.2 (audio) and E.3 (particles) will
each register a concrete sink that translates their hook types into
real-world effects.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
AnimationSequencer now walks every integer frame boundary crossed in a
tick (ACE Sequence.update_internal pattern), dispatching AnimationHook
objects whose Direction matches the playback direction (Forward or
Backward) or is Both. Mirrors ACE's Sequence.execute_hooks exactly.
New public API:
- ConsumePendingHooks() drains all hooks fired since last call, including
AnimationDone sentinel on link-node drain (emote/attack completion).
- ConsumeRootMotionDelta() drains accumulated PosFrames root motion;
AFrame.Combine (forward) / AFrame.Subtract (backward) applied per
crossed frame to match retail.
- CurrentVelocity / CurrentOmega expose the active MotionData's velocity
and omega (scaled by speedMod at enqueue), letting downstream physics
integrate the animation-driven motion.
All 27 AnimationHookType variants (SoundHook, AttackHook,
CreateParticleHook, ReplaceObjectHook, DefaultScriptHook, SetOmegaHook,
TransparentHook, ScaleHook, SetLightHook, etc.) now flow through the
hook queue. Consumers in E.2/E.3 (audio + particles) will route them to
the right subsystems.
9 new tests cover: forward-hook crossing fires exactly once, Both-direction
fires in either direction, Forward-only suppressed on reverse playback,
Backward fires on reverse, PosFrames accumulation + drain, Velocity
exposure + speedMod scaling, AnimationDone fires on link drain.
Build green; 470 tests → 479 (361 Core + 9 new E.1 hook tests + 109 Net).
Ref: docs/research/deepdives/r03-motion-animation.md §5 (hooks), §7.1-7.2
(PosFrames), §7.3 (negative framerate).
Ref: ACE Sequence.cs:262 (execute_hooks), Sequence.cs:351-443
(update_internal per-frame crossing walk).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
The actual retail behavior for jump animations is a plain SubState swap —
NOT an Action overlay as I'd initially guessed. MotionCommand.Falling
(0x40000015) is a SubState cycle whose motion-table entries handle the
whole jump lifecycle:
- Links[(stance, RunForward)][Falling] = leap-into-air link
- Cycles[(stance, Falling)] = airborne cycle (loops)
- Links[(stance, Falling)][Ready/...] = landing link back to normal
Empirical verification from the diagnostic dump:
Links[0x003D0007] has 3 inner entries:
inner key: 0x41000003 (Ready)
inner key: 0x45000005 (WalkForward)
inner key: 0x40000015 (Falling) ← jackpot
SetCycle() already handles SubState + Links + Cycles resolution correctly,
so the whole fix is three lines:
if (!result.IsOnGround)
animCommand = MotionCommand.Falling;
What's in this commit:
- Added MotionCommand.Falling (0x40000015) constant + comments explaining
the retail jump-is-a-SubState flow
- GameWindow.UpdatePlayerAnimation swaps to Falling when airborne (the
cleanest possible implementation — motion table does all the work)
- Kept AnimationSequencer.PlayAction infrastructure (ported via Links
fallback + Modifiers fallback). Not needed for jump, but perfectly
valid for emotes like /wave, /bow (found in the same Links dict as
inner keys 0x13000080-0x13000083) and eventual combat attacks
- Kept MotionCommand.Jump / Jumpup / FallDown constants (unused for now
but useful reference if non-humanoid motion tables use them)
- Removed all diagnostic logging
What was learned (for future motion work):
- Retail's MotionTable.Cycles dict holds SubState loops (Ready, Walk,
Run, Falling, Crouch, etc.) by (style<<16) | (motion & 0xFFFFFF)
- MotionTable.Links dict holds TRANSITIONS between motions: the OUTER
key is the (style, fromMotion) combo; the INNER key is the TARGET
motion. The stored MotionData IS the link animation played during
the transition. This is what ACE's get_link traverses.
- MotionTable.Modifiers dict holds overlay motions (mask 0x20) — rare
for humanoids, only 8 TurnRight/SideStepRight stance variants
- Actions (mask 0x10) in retail ALSO go through Links — they're
transition animations FROM current substate, not overlays. Use
PlayAction (now correctly routed to Links dict) for them.
Jump animation now works retail-faithfully for running + jumping off.
Standing-jump behavior depends on whether the player's motion table
has a Ready→Falling link; SetCycle's fallback chain should handle it
via the style-level catch-all if the direct link is absent.
470 tests pass. Build clean.
Adds AnimationSequencer.PlayAction as the proper path for Action and
Modifier-class motions (the MotionTable.Modifiers dict, distinct from
Cycles). Action nodes are inserted before the looping cyclic tail so
they drain once and the cycle resumes naturally — leveraging the
sequencer's existing "non-looping head drains, cyclic tail wraps"
queue semantics.
What this does:
- New AnimationSequencer.PlayAction(motionCommand, speedMod=1f):
- Resolves (style<<16) | (motion&0xFFFFFF) from MotionTable.Modifiers
- Falls back to (motion&0xFFFFFF) plain key
- Silent no-op when not found (some motion tables lack these)
- Inserts AnimNodes before _firstCyclic; re-points the cursor when on
the cyclic tail so the action plays immediately
- New MotionCommand.Jump (0x2500003B) + MotionCommand.FallDown (0x10000050)
constants.
- GameWindow.UpdatePlayerAnimation fires PlayAction(Jump) on
result.JumpExtent.HasValue and PlayAction(FallDown) on JustLanded.
Key research finding: retail does NOT animate jumps.
- ACE Player.HandleActionJump explicitly clears PendingMotions and sets
IsAnimating=false during a jump (Player.cs:914-915).
- Empirical verification: the player humanoid's MotionTable only has 8
Modifier entries — all TurnRight/SideStepRight stance variants. No
Jump (0x2500003B) or FallDown (0x10000050) entries.
- Jump is a physics-only action: the character keeps whatever cycle
was active (walk/run/idle) while the physics body arcs through the
air. There is no "raise arms to jump" pose in retail.
PlayAction is still called on jump/land as a safety hatch for creature
Setups that DO carry leap animations in their Modifiers dict (drudge
jumps, monster pounces, etc.). For player humanoids it's a no-op. The
infrastructure is also ready for future emote/combat actions that
legitimately use the Modifiers dict.
470 tests pass, build clean.
Adds the first on-screen HUD for the dev client plus today's mouse-control
refinements. Also lands yesterday's scenery-alignment changes that were
left uncommitted in the working tree.
Overlay:
- BitmapFont rasterizes a system TTF via StbTrueTypeSharp into a 512x512
R8 atlas at startup (Consolas on Windows, DejaVu/Menlo fallbacks)
- TextRenderer batches 2D quads in screen-space with ortho projection;
one shader + two draw calls (rect then text) for panel backgrounds
under glyphs
- DebugOverlay composes info / stats / compass / help panels on top of
the 3D scene; toggles via F1/F4/F5/F6; transient toasts for key events
- DebugLineRenderer and its shaders (carried over from the scenery work)
are properly committed in this commit
Controls:
- Per-mode mouse sensitivity (Chase 0.15, Fly 1.0, Orbit 1.0); F8/F9 to
adjust the active mode multiplicatively (x1.2)
- Hold RMB to free-orbit the chase camera around the player; release
stays at the new angle (no snap-back)
- Mouse-wheel zooms chase distance between 2m and 40m
- Chase pitch widened to [-0.7, 1.4] so mouse-Y tilts both ways from
the default neutral angle
Scenery alignment (carried from yesterday's session):
- ShadowObjectRegistry AllEntriesForDebug + Scale field
- SceneryGenerator uses ACViewer's OnRoad polygon test + baseLoc +
set_heading rotation
- BSPQuery dispatchers accept localToWorld so normals/offsets transform
correctly per part
- TransitionTypes.CylinderCollision rewritten with wall-slide + push-out
- PhysicsDataCache caches visual-mesh AABB for scenery that lacks
physics Setup bounds
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>
Rewind to t-0.02 instead of exact contact time, plus 2cm normal
push-back. The previous 0.5cm was too small — at high speed the
sub-step could overshoot past the surface.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
When FindTransitionalPosition fails (stuck in corner, too many steps),
use the partially-resolved position instead of falling back to the
simple Resolve which has no object collision. This prevents walking
through objects when the transition can't find a clean path.
The player now stops at corners instead of clipping through.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
The broad-phase rejection was using 3D distance for cylinder objects,
which includes the Z offset between player feet and cylinder base.
Trees have their origin at the base (Z=ground) while the player
sphere is at chest height (Z=ground+~2.5m). The 3D distance exceeded
the combined radius, causing the collision test to be skipped entirely.
Fix: use horizontal (XY) distance for cylinder broad-phase since
the vertical extent is checked separately in the cylinder test.
Also increase broad-phase margin from 1m to 2m.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
GetNearbyObjects now searches the player's landblock plus all 8
neighbors. Previously only searched one landblock, missing objects
near landblock boundaries — which includes most trees/rocks since
scenery is placed across the full streaming window.
Also added diagnostic logging (will strip after verification).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
When collision is detected at t=0 (already overlapping at step start),
push the sphere out along the collision normal by half-radius instead
of trying to slide with zero displacement (which gets stuck).
Returns Adjusted instead of Slid so the transition loop retries
from the pushed-out position.
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>
Most scenery objects (trees, rocks) use CylSphere collision from
their Setup, not PhysicsBSP. Register these in ShadowObjectRegistry
with a Cylinder collision type. FindObjCollisions now handles both:
- BSP: full polygon collision via BSPQuery (buildings, stabs)
- Cylinder: radial + vertical cylinder-sphere test (trees, NPCs)
Diagnostics showed 170 CylSphere entities vs 278 BSP entities in
the Holtburg landblock alone — this roughly doubles collision coverage.
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>
Replace simplified push-out with retail-faithful SlideSphere and
AdjustOffset from transition_pseudocode.md. Crease-projection between
collision normal and contact plane produces smooth wall-sliding.
Object collision uses proper rotation transform to object-local space.
SlideSphere (section 6): computes crease direction via cross product
of collision normal and contact plane normal, projects displacement
onto the crease, then applies the correction offset. Handles three
cases: crease exists, parallel same-direction, parallel opposing.
AdjustOffset (section 6): adds safety check to keep sphere above
contact plane by computing signed distance and pushing up along Z
when the sphere dips below.
FindObjCollisions: removes ad-hoc penetration push-out, now calls
SlideSphere after BSP hit detection for proper wall-slide behavior.
Also fixes: ShadowEntry gains Rotation field, tests updated to match
Register signature, unused variables removed from GameWindow.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Register static entities into terrain cells during streaming.
Transition system queries nearby objects and runs BSP collision.
Player can no longer walk through trees and buildings.
- ShadowObjectRegistry: 24m×24m cell index, Register/Deregister/
RemoveLandblock/GetNearbyObjects matching retail AC's approach
- PhysicsEngine: ShadowObjects property + DataCache wiring point;
RemoveLandblock now also clears shadow objects; TryGetLandblockContext
helper lets Transition resolve landblock id+offset for a world pos
- Transition.FindObjCollisions: queries registry, broad-phase sphere test,
narrow-phase BSPQuery.SphereIntersectsPoly in object-local space,
returns Slid on hit to redirect movement along the surface
- GameWindow.ApplyLoadedTerrainLocked: registers each static entity after
physics BSP data is cached; selects radius from BSP bounding sphere or
Setup.Radius; wires PhysicsDataCache into engine on OnLoad
- 16 new ShadowObjectRegistry unit tests, all 361 tests green
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Replace simple Z-snap PhysicsEngine.Resolve with ResolveWithTransition
that uses the ported CTransition sphere-sweep pipeline. Movement is
subdivided into sphere-radius steps, terrain collision tested at each
step with step-down for ground contact maintenance.
Falls back to simple Resolve if transition fails. Player controller
now passes pre/post integration positions to the transition system.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
SmallVelocity threshold (0.25 m/s) in UpdatePhysicsInternal was zeroing
velocity every frame while airborne at the jump apex. With vel~0.01 m/s
and gravity adding only 0.012/frame, the zeroing won every frame and
the character got stuck at peak height forever.
Fix: only apply small-velocity zeroing when OnWalkable (grounded).
While airborne, gravity must accumulate freely through the zero-crossing.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Two fixes for jump physics:
- Skip ground-snap when velocity Z > 0 (prevents immediate re-landing
at high framerates where per-frame Z delta < 0.05 snap threshold)
- Guard apply_current_movement velocity write behind OnWalkable check
(prevents MotionInterpreter.DoMotion from zeroing jump velocity on
every frame while airborne)
- Guard PlayerMovementController velocity replacement behind OnWalkable
(preserves momentum during airborne flight)
Jump works locally but server packet not yet sent (BUG-002).
Facing direction mismatch logged as BUG-003.
RunRate not verified as BUG-004.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Port FindTransitionalPosition, TransitionalInsert, FindEnvCollisions,
AdjustOffset, DoStepDown, ValidateTransition from transition_pseudocode.md.
Outdoor terrain collision with step-down ground contact. Indoor BSP and
object collision deferred to subsequent tasks.
Also adds PhysicsEngine.SampleTerrainZ() which dispatches the terrain Z
query to the right registered landblock by world-space XY position.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
SpherePath, CollisionInfo, ObjectInfo, TransitionState, PhysicsGlobals.
Types match the pseudocode from transition_pseudocode.md, faithful to
decompiled CTransition + ACE Transition.cs naming.
Co-Authored-By: Claude Sonnet 4.6 <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>
Implements IWeenieObject with GetRunRate and GetJumpHeight from
decompiled client, cross-referenced against ACE MovementSystem.
Default skills (Run=200, Jump=100) used until skill parsing ships.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Sprint 2 of the audit remediation plan.
Re-enables the outdoor→indoor portal transition in PhysicsEngine with
an added containment check: after detecting a portal plane crossing,
verify the target cell's floor polygon actually covers the candidate
position AND the floor Z is within step height of the player's Z.
This prevents the wall-bounce bug (where portal planes on upper
floors captured outdoor positions) while allowing genuine doorway
transitions. Without full CellBSP, the SampleFloorZ + Z-proximity
check is the best available approximation per the indoor transition
research (docs/research/acclient_indoor_transitions_pseudocode.md).
Source: ACE EnvCell.find_transit_cells validates via
sphere_intersects_cell in the target cell's local space. Our
SampleFloorZ + Z check is the equivalent without BSP.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
ROOT CAUSE of "twitching" / stuck-on-frame-0 for reverse animations
(TurnRight with negative dat framerate, StrafeRight, etc.):
The frame swap (StartFrame↔EndFrame for negative speed) made EndFrame=0,
and GetStartFramePosition returned (0+1)-eps = 0.999. The cursor
oscillated between 0.0 and 0.999 — floor() of anything in [0,1) is
always 0, so only frame 0 ever rendered.
Fix: DON'T swap. Keep StartFrame=0, EndFrame=N-1 regardless of speed
sign. GetStartFramePosition for negative speed returns (N-1+1)-eps ≈ N,
so the cursor starts near the high end and counts down through ALL
frames. The Advance loop's reverse boundary check uses StartFrame (the
low value) correctly without the swap.
Also strips diagnostic logging from AnimationSequencer and GameWindow.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Complete ground-up rewrite of AnimationSequencer.cs using the retail AC client
pseudocode (docs/research/acclient_animation_pseudocode.md) as the direct
translation guide. Every key algorithmic difference from the previous patched
implementation is addressed:
1. _framePosition is now double (64-bit), matching Sequence+0x30 in the retail
client binary. Previously float, which accumulated rounding error over long
sessions.
2. FUN_005267E0 (multiply_framerate) is now correctly applied at node load time:
negative speedScale swaps startFrame↔endFrame so the advance loop counts DOWN
from (EndFrame+1)-epsilon toward EndFrame, exactly matching the retail layout.
3. update_internal (FUN_005261D0) is faithfully ported: one loop handles both
forward and reverse; boundary detection uses EndFrame as the lower bound for
reverse playback (matching the post-swap field semantics); remainder time
propagates correctly across node boundaries for large dt values.
4. GetStartFramePosition (FUN_00526880) and GetEndFramePosition (FUN_005268B0)
formulas are now correct: negative speed starts at (EndFrame+1)-epsilon,
ends at StartFrame; positive speed starts at StartFrame, ends at (EndFrame+1)-epsilon.
5. advance_to_next_animation (FUN_00525EB0) wraps to _firstCyclic when the
linked list is exhausted, matching the retail loop-forever semantics.
6. adjust_motion (ACE MotionInterp.cs:394-428) remapping is unchanged and
correct: TurnLeft→TurnRight, SideStepLeft→SideStepRight (negate speed),
WalkBackward→WalkForward (negate×0.65 BackwardsFactor).
7. SlerpRetailClient (FUN_005360d0) is unchanged — the pseudocode confirms the
existing implementation is correct.
AnimationSequencerTests grows from 9 to 17 tests:
- Negative-speed playback: TurnLeft remaps and cursor initializes near EndFrame+1
- Reverse frame position decreases (not increases) over time
- Reverse wrap at start boundary recovers and loops
- advance_to_next_animation: link node drains then enters cycle
- Cycle loops repeatedly without crash or position drift
All 431 tests green (109 net + 322 core).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Backward-playback nodes (TurnLeft, SideStepLeft) have LowFrame >
HighFrame after multiply_framerate swaps them. Math.Clamp(x, 19, 0)
throws because min > max.
Fix: compute rangeLo/rangeHi from Min/Max of Low/High, use those
for clamping. Also step nextIdx in the playback direction (forward
+1, backward -1) instead of always +1.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
ROOT CAUSE FIX for missing left-side animations.
The AC client's MotionTable has NO cycles for TurnLeft (0x000E),
SideStepLeft (0x0010), or WalkBackward (0x0006). The real client
calls adjust_motion() which remaps these to their right-side
equivalents with NEGATIVE speed before looking up the cycle. Then
multiply_framerate() swaps LowFrame↔HighFrame so the animation
plays backward.
Source: ACE MotionInterp.cs:394-428, decompiled FUN_005267E0.
Changes:
- AnimationSequencer.SetCycle: adds adjust_motion block that remaps
left→right with speed *= -1 (TurnLeft, SideStepLeft) or
speed *= -0.65 (WalkBackward = BackwardsFactor)
- LoadAnimNode: when framerate < 0, swaps Low↔High (matching the
decompiled multiply_framerate)
- GameWindow.UpdatePlayerAnimation: passes original animCommand to
SetCycle (sequencer handles remapping internally), keeps legacy
fallback for non-sequencer entities
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Port the animation playback engine from the decompiled retail client
into AcDream.Core.Physics.AnimationSequencer.
## What this adds
**AnimationSequencer** (src/AcDream.Core/Physics/AnimationSequencer.cs):
- Frame advancer: `frameNum += framerate * dt`, bounds-checks against
AnimData.HighFrame/LowFrame (with sentinel resolution for HighFrame=-1),
wraps at cycle boundaries. Matches ACE's `Sequence.update_internal`.
- Quaternion slerp (`SlerpRetailClient`): ported from decompiled
`FUN_005360d0` (chunk_00530000.c:4799-4846):
1. dot-product sign-flip to take the shorter arc
2. fallback to linear blend when 1-dot <= 1e-4 (near-parallel)
3. sin-based slerp for all other cases
4. validate weights lie in [0,1] before using sin result (retail
client validation step that guards degenerate inputs)
- Transition link resolution: `GetLink(style, fromMotion, toMotion)`
mirrors ACE's `MotionTable.get_link` positive-speed path.
DatReaderWriter layout: `Links[style<<16|(from&0xFFFFFF)]` is a
`MotionCommandData` whose `.MotionData[toMotion]` is the transition
`MotionData`. Link frames are prepended before the cyclic tail, so
idle->walk plays the short transition clip then loops the walk cycle.
- `IAnimationLoader` / `DatCollectionLoader`: thin abstraction so the
sequencer is testable offline without opening dat files.
- Public API: `SetCycle(style, motion, speedMod)` + `Advance(dt)`
returning `IReadOnlyList<PartTransform>` (Origin+Orientation per part).
**AnimationSequencerTests** (tests/...Physics/AnimationSequencerTests.cs):
14 tests, all offline, covering slerp math, frame wrap, transition link
prepend, no-link direct switch, same-motion fast path, reset.
317 tests green, 0 warnings.
Co-Authored-By: Claude Opus 4.6 (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>
The SampleZ method had the two triangle-boundary conditions swapped relative
to what the mesh index buffer actually renders, causing the physics Z to
sample from the wrong triangle on roughly half of all terrain cells. The
error could be up to 7.5 units on steep 24×24 cells, which manifested as
feet clipping into rising terrain on slopes.
Root cause (discovered via WorldBuilder-ACME-Edition exhaustive analysis):
"SWtoNE cut" means BL and TR are the *isolated* vertices; the shared
hypotenuse runs TL(0,1) → BR(1,0), so the correct dividing test is
tx+ty=1, NOT ty=tx. The old code used ty≤tx for the SWtoNE branch
(the BL→TR diagonal), which matches the SEtoNW mesh layout instead.
Fix: swap the boundary conditions for the two split cases so they match
LandblockMesh.cs's actual index buffer layout:
SWtoNE: tx+ty ≤ 1 → BL+BR+TL, else TR+TL+BR
SEtoNW: ty ≤ tx → BL+BR+TR, else BL+TR+TL
Verified by running all three formulas (acdream, ACME GetHeight, ACME
HeightSampler) against the mesh index buffer at 50 interior points across
both split types: fixed version matches 0 errors, old version had 50.
All 283 tests still pass.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
The triangle-aware Z sampling from the previous commit produces exact
terrain-surface Z values, but a point-sampled Z on a tilted surface
places the character's center on the surface while their feet (which
extend horizontally) clip into the rising terrain ahead/behind.
Fix: in PlayerMovementController, sample Z 1 unit ahead in the walk
direction and add 40% of the gradient as an upward bias. This
compensates for the character's collision cylinder radius on slopes
while producing zero bias on flat ground. The bias is applied in the
movement controller (gameplay concern) not in TerrainSurface.SampleZ
(which stays exact for physics/tests).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Two fundamental terrain fixes based on the AC2D + holtburger deep dive:
1. Terrain split formula: replaced WorldBuilder's physics-path formula
(214614067/1813693831) with AC2D's render-path formula (0x0CCAC033,
0x421BE3BD, 0x6C1AC587, 0x519B8F25). The two produce different splits
for some cells. Since the render mesh uses this formula, the physics
Z sampler must match it to avoid misalignment on slopes.
2. Triangle-aware Z: replaced bilinear interpolation in TerrainSurface
with per-triangle barycentric interpolation. Each cell is split into
two triangles (using the same AC2D formula). SampleZ determines which
triangle the query point falls in, then interpolates within that
triangle. This produces Z values that exactly match the visual terrain
mesh — no more slope clipping.
Removes the multi-point Z sampling hack from PlayerMovementController
(no longer needed with exact triangle Z).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Two targeted fixes for user-reported movement bugs:
1. Wall bounce: PortalPlane.FromVertices now accepts ALL polygon vertices
(not just 3) for accurate centroid + bounding radius. IsCrossing uses
2D (XY) distance check with tight radius (no multiplier) to prevent
wall faces from triggering false indoor transitions. Walking along a
building wall no longer launches the player into the air.
2. Slope alignment: PlayerMovementController adds a slope-proportional
Z bias when walking uphill (up to +0.8 on steep slopes, grounded
only). Prevents feet from sinking into the visual terrain mesh on
slopes where the physics sample point lags the render surface.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Portal planes are infinite — IsCrossing only checked if positions
were on opposite sides of the plane, without verifying the crossing
point was near the actual portal opening. Walking 50m from a
building but crossing the same plane extension triggered false indoor
transitions, sinking the player into underground cell floors.
Fix: FromVertices now computes centroid (average of 3 vertices) and
bounding radius (max vertex distance + 2 unit padding). IsCrossing
rejects crossings where both positions are further than 2×radius
from the centroid. Only nearby crossings (within doorway range)
trigger a transition.
Also fixes jump-not-landing: the false portal transitions were
producing wrong resolvedGroundZ values during the jump arc, making
the landing check (candidateZ <= resolvedGroundZ) never true.
283 tests still green.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Adds the foundational portal-plane record for cell transition detection.
PortalPlane.FromVertices computes a normalised plane from 3 coplanar
polygon vertices via cross product + dot product; IsCrossing tests whether
a movement vector straddles the plane (strictly negative dot-product
product — exact-on-plane position returns false as specified).
4 new unit tests: normal construction, opposite-side crossing, same-side
no-crossing, start-on-plane no-crossing. All 269 tests green.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Three attempts at guarding the indoor transition (cellId mask,
Z threshold, terrainZ comparison) all failed because CellSurface
floor polygons are too aggressive — building footprints, roofs, and
upper floors all have PhysicsPolygons that cover wide XY areas at
various Z levels, and ANY outdoor position near a building matches
a cell floor. The proper solution is portal-based transition
(CellPortal boundary crossing), not floor-polygon containment —
but that's Phase E scope.
For the B.2 MVP: outdoor players NEVER transition to indoor cells.
The else-if branch is compiled out with `if (false)`. Indoor→outdoor
transition (walking OUT of a building) is also effectively disabled
since you can't get indoors in the first place. Walking on outdoor
terrain works correctly; walking into buildings will be blocked by
the terrain heightmap (you walk on the roof-level terrain, not
through the building).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Previous cellId-mask fix was necessary but insufficient: the engine
correctly identified the player as outdoor, but then immediately
transitioned to an indoor cell because a CellSurface floor polygon
covered the player's XY at a Z within stepUpHeight. The floor
polygon was a roof or upper floor of a nearby building that happens
to sit at terrain level — not a walkable indoor floor the player
should snap to.
Fix: outdoor→indoor transition now requires bestCellZ < terrainZ - 1.
A genuine indoor transition is into a cell whose floor is BELOW the
terrain surface (basement, ground floor of elevated building). Cells
at or above terrain Z are roofs/upper floors viewed from outside and
must not capture the player.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
ROOT CAUSE of the fall-through-ground bug. The currentlyIndoor check
compared the FULL 32-bit cell ID (0xA9B40001, includes landblock
prefix) against 0x0100. Every outdoor cell ID with a landblock
prefix is >= 0x0100, so the engine ALWAYS took the "stay indoors"
path, snapping the player to the nearest EnvCell floor at Z=66
instead of the outdoor terrain at Z=94.
ACE confirmed the bug: "AddWorldObjectInternal: couldn't spawn
+Acdream at 0xA9B40121 [84.2 37.7 66.0]" — we were sending the
server an indoor cell ID with a below-terrain Z position.
Fix: mask cellId with 0xFFFF before the indoor check (outdoor
cells are 0x0001–0x0040; indoor are 0x0100+; the high 16 bits
are the landblock prefix and must be stripped). Also mask the
returned targetCellId from CellSurface (which carries the full
EnvCell dat id) to just the cell index.
265 tests still green.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Three more fixes from the diagnostic dump:
1. Initial position: PhysicsEngine.Resolve was mapping the player
into an indoor EnvCell (foundry at Z=66) when they're standing
on outdoor terrain at Z=93+. The cell-containment check was too
aggressive for initial placement. Now uses the server-sent
position directly — the server already gave us a valid position.
2. Yaw unbounded: mouse delta accumulated without wrapping, growing
to 24+ radians. Now wraps to [-PI, PI] after every turn.
3. Turn command spam: MouseDeltaX > 0.5 threshold was too low for
raw pixel deltas. Any mouse jitter triggered turnCmd flips every
frame → stateChanged=True → MoveToState flood to the server.
Mouse turning now only affects yaw directly; turn COMMANDS only
come from A/D keyboard (matching retail client behavior where
mouse-look doesn't generate a TurnRight/TurnLeft command).
265 tests still green.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Combines TerrainSurface + CellSurface into a single Resolve() API
that handles outdoor terrain walking, indoor floor walking,
outdoor<->indoor cell transitions, step-height enforcement, and
ground detection.
Step-height blocks upward Z deltas exceeding the limit (walls,
cliffs); downhill movement is always accepted. Indoor transitions
pick the cell whose floor Z is closest to the entity's current Z
(handles multi-story buildings). Reports IsOnGround=false when
no landblock or surface covers the entity's position (gravity
applied by the caller).
One API mismatch fixed vs plan: plan encoded the upper 16 landblock
bits into the returned cell ID, but the tests assert the raw cell ID
(0x0100, <0x0100) — so Resolve returns targetCellId directly.
6 new tests covering flat terrain, slopes, step-height rejection,
indoor entry/exit, and void detection. 243 total, all green.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Extracts the bilinear heightmap interpolation from GameWindow's
inlined SampleTerrainZ into a reusable class. Also adds outdoor
cell ID computation (8×8 grid of 24-unit cells, 0x0001..0x0040).
First component of the physics collision engine.
6 new tests, all green.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Projects an XY point onto a cell's floor polygons via brute-force
triangle iteration + barycentric Z interpolation. Fan-triangulates
quads and larger polygons. Returns null when outside all floor
surfaces. Accepts pre-transformed world-space vertex positions so
the caller handles EnvCell coordinate transforms.
Second component of the physics collision engine.
4 new tests, all green.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
