# Session Handoff - February 5, 2026

## Session Summary
Enhanced Gantt chart visualization system with sequence names, adaptive tick intervals, and improved layout.

## Completed Work

### 1. Gantt Chart Enhancements (Commit: abd1d77)

**Optional Sequence Names:**
- New syntax: `SEQUENCE <start> <priority> ["name"] [optional_end]`
- Example: `SEQUENCE 0 0 "Opening Scene" [5.0]`
- Names displayed in both ASCII and HTML Gantt charts
- Backward compatible (names are optional)

**Adaptive Tick Intervals:**
- Fixed hardcoded 5s ticks to be duration-based:
  - ≤5s: 1s intervals
  - ≤40s: 2s intervals (demo.seq now shows 0,2,4,6...36 instead of 0,5,10...35)
  - ≤100s: 5s intervals
  - >100s: 10s+ intervals
- Implemented in `calculate_tick_interval()` helper function

**Chronological Sorting:**
- Sequences now displayed in start-time order regardless of definition order
- Applies to both ASCII and HTML output

**Visual Separators:**
- Horizontal separator lines (────) between sequences in ASCII
- Dashed separator lines in HTML/SVG
- Improves readability for complex timelines

**Files Modified:**
- `tools/seq_compiler.cc`: Core implementation (+111 lines)
- `doc/SEQUENCE.md`: Updated syntax reference with examples
- `assets/demo.seq`: Updated quick reference header

## Current State

**Build Status:** ✅ All targets building successfully
- Demo compiles and runs
- 14 sequences, 32.5s duration
- Gantt charts generated correctly

**Documentation:** ✅ Up to date
- SEQUENCE.md includes name syntax and examples
- demo.seq quick reference updated
- No TODOs or pending documentation

**Testing:**
- Verified with test files (test_names.seq)
- Confirmed sorting works with out-of-order sequences
- Tick intervals validated for various durations (12s, 32.5s)
- Generated files cleaned up

## Generated Artifacts
- `demo_gantt.txt`: ASCII visualization with 2s ticks, 14 sequences sorted
- `demo_gantt.html`: Interactive HTML/SVG version
- Both available in project root (gitignored)

## Architecture Notes

**SequenceEntry Struct:**
```cpp
struct SequenceEntry {
  std::string start_time;
  std::string priority;
  std::string end_time;  // -1.0 = no explicit end
  std::string name;      // empty = no name
  std::vector<EffectEntry> effects;
};
```

**Name Parsing Logic:**
- Reads tokens after `<start> <priority>`
- `"quoted string"` → sequence name (supports multi-word)
- `[bracketed]` → end time
- Both optional, order-independent
- Error on unrecognized tokens

**Tick Interval Display:**
- ASCII: Iterates through columns, checks distance to tick positions
- HTML: Direct iteration through tick_interval values
- Both use same `calculate_tick_interval()` heuristic

## Next Steps (None Pending)
- All requested features implemented
- No blocking issues or TODOs
- System ready for use

## Session Context
- Started: Investigation of sequence end time verification (already completed)
- User requests: (1) Sort sequences by time, (2) Add separators, (3) Optional names, (4) Fix tick intervals
- All requests completed in single session
- Commit: "feat: Enhance Gantt charts with sequence names, adaptive ticks, and sorting"

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*handoff(Claude): Gantt chart visualization enhanced with names, adaptive ticks, sorting, and separators. All features tested and documented.*