Ports retail's ParticleEmitterInfo / Particle::Init / Particle::Update
(0x005170d0..0x0051d400) and PhysicsScript runtime to a C# data-layer
plus a Silk.NET billboard renderer. Sky-PES path is debug-only behind
ACDREAM_ENABLE_SKY_PES because named-retail decomp confirms GameSky
copies SkyObject.pes_id but never reads it (CreateDeletePhysicsObjects
0x005073c0, MakeObject 0x00506ee0, UseTime 0x005075b0).
Post-review fixes folded into this commit:
H1: AttachLocal (is_parent_local=1) follows live parent each frame.
ParticleSystem.UpdateEmitterAnchor + ParticleHookSink.UpdateEntityAnchor
let the owning subsystem refresh AnchorPos every tick — matches
ParticleEmitter::UpdateParticles 0x0051d2d4 which re-reads the live
parent frame when is_parent_local != 0. Drops the renderer-side
cameraOffset hack that only worked when the parent was the camera.
H3: Strip the long stale comment in GfxObjMesh.cs that contradicted the
retail-faithful (1 - translucency) opacity formula. The code was
right; the comment was a leftover from an earlier hypothesis and
would have invited a wrong "fix".
M1: SkyRenderer tracks textures whose wrap mode it set to ClampToEdge
and restores them to Repeat at end-of-pass, so non-sky renderers
that share the GL handle can't silently inherit clamped wrap state.
M2: Post-scene Z-offset (-120m) only fires when the SkyObject is
weather-flagged AND bit 0x08 is clear, matching retail
GameSky::UpdatePosition 0x00506dd0. The old code applied it to
every post-scene object — a no-op today (every Dereth post-scene
entry happens to be weather-flagged) but a future post-scene-only
sun rim would have been pushed below the camera.
M4: ParticleSystem.EmitterDied event lets ParticleHookSink prune dead
handles from the per-entity tracking dictionaries, fixing a slow
leak where naturally-expired emitters' handles stayed in the
ConcurrentBag forever during long sessions.
M5: SkyPesEntityId moves the post-scene flag bit to 0x08000000 so it
can't ever overlap the object-index range. Synthetic IDs stay in
the reserved 0xFxxxxxxx space.
New tests (ParticleSystemTests + ParticleHookSinkTests):
- UpdateEmitterAnchor_AttachLocal_ParticlePositionFollowsLiveAnchor
- UpdateEmitterAnchor_AttachLocalCleared_ParticleFrozenAtSpawnOrigin
- EmitterDied_FiresOncePerHandle_AfterAllParticlesExpire
- Birthrate_PerSec_EmitsOnePerTickWhenIntervalElapsed (retail-faithful
single-emit-per-frame behavior)
- UpdateEntityAnchor_WithAttachLocal_MovesParticleToLiveAnchor
- EmitterDied_PrunesPerEntityHandleTracking
dotnet build green, dotnet test green: 695 / 393 / 243 = 1331 passed
(up from 1325).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Two independent investigations (in-house decomp re-check + two
external agent reports) converged on the same root cause for the
"too blue-white sky" symptom:
acdream computed SunColor = DirColor × DirBright and AmbientColor =
AmbColor × AmbBright. Retail computes them from the magnitude of a
specially-shaped sun vector instead. Per the named retail decomp:
SkyDesc::GetLighting at 0x00500ac9 (decomp 261343-261353):
sunVec.x = sin(H_rad) × DirBright × cos(P_rad)
sunVec.y = cos(P_rad) ← NOT scaled by DirBright
sunVec.z = DirBright × sin(P_rad)
PrimD3DRender::UpdateLightsInternal at 0x0059b57c (decomp 424118):
D3DLIGHT9.Diffuse.r = sunlight_color.r × sqrt(x²+y²+z²)
SmartBox::SetWorldAmbientLight callsite at 0x0050560b (decomp 267117):
SetWorldAmbientLight(sqrt(|sunVec|²) × 0.2 + ambient_level, ...)
Y stays unscaled by DirBright on purpose, so |sunVec| ≠ DirBright in
general — the magnitude varies with sun pitch/heading. That's what
gives retail's "sun feels stronger when it's overhead, ambient warms
up at midday" behavior we were missing.
Added SkyStateProvider.RetailSunVector(kf) that builds the vector
verbatim. SkyKeyframe.SunColor / AmbientColor now compose via |sunVec|.
SunDirectionFromKeyframe normalizes the same vector (replaces our
geometrically-clean spherical convention which didn't match retail's
deliberate Y-decoupled-from-heading shape).
Tests:
- Replaced the linear-interp assumption in
Interpolate_BetweenKeyframes_LerpsColors with a test on the RAW
inputs (DirColor, AmbBright, etc.) — those still lerp linearly;
the composite SunColor doesn't, intentionally.
- Added 4 golden-value tests for the new formulas
(RetailSunVector_AtZenith, _AtHorizonNorth,
SunColor_UsesRetailMagnitudeNotDirBrightDirectly,
AmbientColor_BoostsByTwentyPercentOfSunVectorLength).
- Updated stale LoadFromRegion_SunColor_IsPrepreMultipliedByBrightness
test to LoadFromRegion_SunColor_UsesRetailSunVectorMagnitude
with the new expected magnitude.
User visually verified — acdream's sky shifted from blue-white toward
the warm tint retail shows at the same keyframe.
1227 tests pass.
Expand the SkyKeyframe record with retail-exact fog fields (FogStart,
FogEnd, FogMode) per r12 §5. The existing FogDensity field is retained
for backwards compat with tests that pin it; new shipping code reads
FogStart / FogEnd / FogMode directly.
Add WeatherSystem (WeatherKind + EnvironOverride enum + 10s transition
ease + deterministic per-day-index roll) matching r12 §6.1. Roll weights
are ~60% Clear / 20% Overcast / 12% Rain / 5% Snow / 3% Storm — tuned
against retail observations. Storm mode triggers lightning flashes
every 8–30 s via an exponential-decay (200ms τ) flash level that the
shader consumes as an additive scene bump.
Add SkyDescLoader that parses the Region dat (0x13000000) into
LoadedSkyDesc — DayGroupData with SkyObjectData (visibility window +
arc sweep), per-keyframe SkyObjectReplaceData, and a shader-ready
SkyStateProvider builder. Sun/ambient colors are pre-multiplied by
DirBright/AmbBright so the shader never needs to know about retail's
scalar brightness field.
19 new tests (weather determinism, transition ease, environ override
tint, flash decay, dat-load conversion with fog + pre-mult colors).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>