Port of gmToolbarUI::HandleSelectionChanged (acclient_2013_pseudo_c.txt:198635).
When the player selects a world object the action bar's bottom strip shows the
object name + (for player/pet/attackable targets) a live Health meter; deselect
clears it. Mana (#140) + stack slider deferred.
- SelectedObjectController (new): clear-then-populate on selection change; sets
name (UiText child, VitalsController pattern), overlay state (ObjectSelected /
StackedItemSelected via UiDatElement.ActiveState), shows the health meter and
sends QueryHealth for health targets. Subscribes via a delegate seam (no
GameWindow coupling).
- GameWindow: _selectedGuid field -> SelectedGuid property + SelectionChanged
event (fires on actual change only); 3 write sites converted, reads untouched.
All selection-write paths (LMB pick, Tab/Q, despawn-clear via Tick()) run on
the render thread, so the event-driven UI mutation is single-threaded.
- WorldSession.SendQueryHealth (0x01BF) — wraps SocialActions.BuildQueryHealth.
- DatWidgetFactory.BuildMeter: handle the single-image toolbar meter shape
(back-track on the element's own DirectState, fill on one Type-3 child). The
sprites go in the TILE slot (DrawMode=Normal tiles to full bar geometry per
UIElement_Meter::DrawChildren) — a left-cap assignment would gap/clamp a
sub-140px sprite. Vitals 3-slice path unchanged.
- ToolbarController.HiddenIds: A1 (health) now owned by SelectedObjectController;
A2 (mana) + A4 (stack) stay hidden (deferred) so their dat back-tracks don't
render as stray empty bars.
Adversarial Opus review found + fixed: the mana-meter orphan (A2 left unhidden)
and the meter tile-vs-cap render bug (C1). Divergence rows AP-46 (health gate
approximation: IsLiveCreatureTarget vs IsPlayer||pet||attackable) + AP-47
(meter shown on select vs on UpdateHealth reply). Spec §5 corrected.
Build + full test suite green (2,684 passed / 4 skipped). Health meter render
fidelity (full-width fill + fraction mapping) pending the user's visual gate.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
6636e50c2a