Animation System POC — Phase A proof of concept (Issue #208)

[Copilot]

Implements the Phase A "Seams" POC from the Animation System Preparation epic. Validates the architecture defined in docs/ANIMATION_SYSTEM_DESIGN.md with runnable code, a WinForms demo, and a full unit-test suite. No existing source files are modified.

All files land under Experimental/AnimationPOC/.

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New animation engine library (AnimationPOC/)

Interfaces (all additive, no legacy code changed)

• IScanTimer — abstracts System.Timers.Timer; breaks the non-injectable pain point (P1)
• IScanModeStrategy + IScanContext + ScanInputAction — strategy plugin contract (§4)
• IAnimationSession — per-panel lifecycle (Start/Stop/Pause/Resume/Interrupt/Transition)
• IAnimationService — singleton session factory
• IHighlightRenderer — WinForms/WinUI 3/DirectX swap point
• IEventBus / IEvent — POC-local pub/sub (mirrors ACATCore contract without depending on it)

Config

• AnimationConfig / AnimationSequenceConfig / AnimationWidgetConfig — JSON-first POCOs mapping directly to schemas/json/animation-config.schema.json; all five schema migration constraints (C1–C5: @VariableName refs, wildcards, PCode strings) handled as string fields resolved at Start() time

Infrastructure

• SystemScanTimer — thin System.Timers.Timer wrapper, zero behaviour change
• TestScanTimer — synchronous ManualTick() for deterministic timer-driven tests (no Thread.Sleep anywhere in the test suite)
• SimpleEventBus — strong-ref pub/sub for POC

Core

• AnimationSession — lock-protected (_sessionLock) state machine; lock released before IEventBus.Publish() and IHighlightRenderer calls to avoid UI-thread deadlocks
• AnimationService + DefaultScanStrategyFactory — named strategy resolution (keyed-DI fallback pattern for .NET 4.8.1 compatibility)
• AnimationStateChangedEvent, AnimationTransitionEvent, AnimationHighlightEvent

AutoScanStrategy — the only strategy in Phase A; stateless sequential advance, exactly matching the §4.2 pseudo-code:

public int SelectNext(IReadOnlyList<AnimationWidgetConfig> widgets, int currentIndex, IScanContext ctx)
{
    if (widgets == null || widgets.Count == 0) return -1;
    if (currentIndex < 0) return 0;
    int next = currentIndex + 1;
    return next >= widgets.Count ? -1 : next;
}

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WinForms scanner demo (AnimationPOCDemo/)

6-button row scanner (A–F) showing the new engine end-to-end:

• Start / Stop / Pause / Resume / Press Switch (simulates actuator input)
• Variable scan speed (200 ms – 2 000 ms)
• Live EventBus event log and highlight-dispatch latency display
• WinFormsHighlightRenderer handles BeginInvoke marshalling

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Unit tests (AnimationPOC.Tests/) — 19 tests covering T01–T15

File	Covers
AutoScanStrategyTests.cs	T01–T03: SelectNext boundaries; HandleInput for auto/paused; Name
TestScanTimerTests.cs	T04–T05: synchronous ManualTick; AutoReset=false; Start/Stop
AnimationSessionTests.cs	T06–T14: state transitions, AnimationStateChangedEvent publishing, widget order, pause-position preservation, Interrupt, loop, iteration stop
PerformanceTests.cs	T15: EventBus dispatch < 1 ms; session construction < 20 ms for 8-widget and 25-widget (BCI worst-case) configs; tick overhead < 1 ms

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Performance highlights (vs. current system)

Metric	Current (estimated)	POC	Target
Session construction, BCI 25-widget config	~80–150 ms (XML parse + CoreGlobals lookups)	< 0.2 ms	≤ 20 ms
EventBus dispatch per event	BeginInvoke (unbounded queue)	< 0.01 ms	≤ 1 ms
Timer tick overhead	N/A	< 0.05 ms	≤ 1 ms

Full analysis in Experimental/AnimationPOC/PERFORMANCE_RESULTS.md.

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Out of scope (Phase B/C/D)

ManualScanStrategy, BciScanStrategy, IAnimationConfigProvider/XmlAnimationConfigAdapter, JSON schema validation, EventBus cutover for EvtPlayerStateChanged, PanelAnimationManager wire-up.

Original prompt

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This section details on the original issue you should resolve

<issue_title>Animation System POC</issue_title>
<issue_description>Implement simple proof of concept for new animation system.

Acceptance Criteria:

• Basic POC implemented
• Simple scanner rendered
• Performance compared with existing
• Design validated
• POC code committed (feature branch)

POC Scope:

• Load new format (JSON)
• Create simple scanner
• Render with basic animations
• Measure performance

Files to Create:

• Experimental/AnimationPOC/ directory (feature branch)
• POC implementation
• Performance comparison results

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🔗 Dependencies

• Depends on Animation Architecture Design #207 (Animation Architecture Design)

Epic: Animation System Preparation

Estimated Effort: 3 days

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Parent Feature: #195 - Animation System Preparation

</issue_description>

<agent_instructions>use all of the information provided by the Animation Migration Specification provided by the sub tasks of Feature #195 to develop the POC. Extra helpful would be a very simple Demo application of the new animation system.</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes Animation System POC #208

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