Two bugs in calendar display (the CLOCK ITSELF was already correct):
1. **Month enum had wrong order + non-retail names.** Old enum:
Snowreap=0, ColdMeet, Leafdawning, Seedsow, Rosetide, Solclaim, ...
At day-of-year 83 this gave month index 2 = Leafdawning. Retail's
@timestamp at the same moment shows "Seedsow 24". Fixed enum to
chronological order starting at year-anchor month Morningthaw, with
retail-canonical names:
Morningthaw=0, Solclaim, Seedsow, Leafdawning, Verdantine,
Thistledown, Harvestgain, Leafcull, Frostfell, Snowreap,
Coldeve, Wintersebb.
At day-of-year 83 → month 2 = Seedsow ✓
2. **ToCalendar returned relative year, not absolute Portal Year.**
We had AbsoluteYear() = relative_year + ZeroYear (=10) but
ToCalendar's Calendar.Year was the relative one. So acdream's
title bar showed "PY 106" while retail's @timestamp at the same
tick showed "PY 116". Fixed ToCalendar to add ZeroYear so the
exposed Calendar.Year matches retail's display.
3. **GameWindow title bar now shows the calendar.** Format mirrors
retail's @timestamp output:
"PY<Year> <Month> <Day> <Hour> (df=<dayFraction>)"
Lets the user read the same fields off both clients and confirm
clock parity directly. Drift > 1 hour = real bug.
Tests:
- Updated ToCalendar_PY10Day1_Morningthaw (renamed from PY0Day1_Snowreap)
- Updated ToCalendar_AdvancesCorrectly (Snowreap→Morningthaw etc.)
- Added regression: ToCalendar_TickAtSeedsow24Year106_MatchesRetailFormat
pinning a retail-known tick → retail-known calendar string.
The dayFraction formula (CalcDayBegin's `arg2 + zero_time_of_year`,
decomp 0x005a6400 line 434549) was already correct; an earlier-this-
session attempt to flip the sign was reverted in this same commit's
parent. The "few minutes drift" observed in dual-client comparisons
this session was a combination of:
- calendar label mismatch (this fix addresses)
- slot-boundary rounding (fixes itself)
- 1-minute wall-clock interpolation drift (within tolerance)
NOT a clock-formula bug. ISSUE #3 in docs/ISSUES.md is now misnamed
("Client clock drifts from retail"); plan to re-title or close in a
follow-up commit after the visual-divergence investigation lands.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
User observed: 'time is flipped — supposed to be day/evening, but shows
night/morning.' That's a ~half-day offset.
Root cause in ACE DerethDateTime.cs line 23:
private const double dayZeroTicks = 0; // Morningthaw 1, 10 P.Y. - Morntide-and-Half
ACE anchors tick 0 to Morntide-and-Half (slot 7 on the 0-indexed 16-slot
scale) — NOT Darktide (slot 0 = midnight) as our DayFraction function
assumed. Confirmed by DerethDateTime.cs:145:
private int hour = (int)Hours.Morntide_and_Half;
Fix: shift DayFraction by +7/16 * DayTicks (3333.75) so tick 0 maps to
its real calendar slot. Exposed as DayFractionOriginOffsetTicks constant
for documentation + downstream referencing.
Effect on sun: previously, server tick ~0 (just-booted ACE) produced
dayFraction 0 → midnight sky → night colors at noon real-time.
Now dayFraction 7/16 = 0.4375 → late morning sky → noon-ish colors
within 1/16 of a day, which matches what a user actually sees when
launching during daytime.
Tests updated for the corrected convention:
- DerethDateTime.DayFraction(0) = 7/16 (not 0).
- CurrentHour(0) = MorntideAndHalf (not Darktide).
- IsDaytime(0) = true.
- Midnight (Darktide, slot 0) is 9/16 of a day past tick 0.
- SkyState + WorldTimeDebug tests retargeted to the new frame.
Build green, 711 tests pass.
Ref: references/ACE/Source/ACE.Common/DerethDateTime.cs:23-25 + :145.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Client-side deterministic sky + weather + day/night system per R12.
Retail's model is 95% client-side: the server just delivers its
current PortalYearTicks (double, seconds since boot-seed) at login and
in TimeSync packets; the client computes everything else locally from
the constants in r12 §1.2 + ACE DerethDateTime.cs.
Core layer (AcDream.Core/World):
- DerethDateTime: retail-exact calendar (16 hours/day, 30 days/month,
12 months/year, 7620 ticks/day, 2,743,200 ticks/year). HourName enum
covers all 16 named half-hour slots (Darktide → GloamingAndHalf);
MonthName covers the 12 Derethian months (Snowreap → Frostfell).
DayFraction, CurrentHour, IsDaytime, ToCalendar.
- SkyKeyframe + SkyStateProvider: 4-keyframe default day/dawn/noon/dusk
with linear color + angular-wrap heading interpolation + slerp-like
shortest-arc lerp so heading wraps 350° → 10° don't tween backwards
through 180°. Default keyframe colors tuned to retail screenshots
(sunrise warm, noon white, sunset red, midnight deep blue).
- WorldTimeService: owns the live clock. SyncFromServer(ticks) sets
baseline; NowTicks advances by real-time elapsed. Exposes DayFraction,
CurrentSky, CurrentSunDirection, IsDaytime for the render thread.
This is the foundation Phase G.2 (dynamic lighting) consumes: lighting
uniforms are fed from CurrentSky's SunColor / AmbientColor / sun
direction, varying smoothly across the day.
Tests (16 new):
- DerethDateTime: midnight, half-day, wrap, Dawnsong, Midsong,
day/night flag at dawn vs Darktide-Half, year rollover, month
advance.
- SkyState: 4-default keyframes, noon-exact matches frame data,
midpoint lerps between neighbours, wrap across midnight doesn't
produce NaN, sun direction returns unit vector, WorldTimeService
sync + DayFraction at noon.
Build green, 587 tests pass (up from 570).
Ref: r12 §1 (Portal Year math), §2 (sky objects), §4 (color lerp).
Ref: ACE DerethDateTime.cs + NetworkSession TimeSync handler.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
