feedBack/plugins/highway_3d/README.md

3D Highway

A 3D note highway visualization for FeedBack — an alternative to the default 2D highway, with a sense of depth and perspective inspired by stage views in modern rhythm games.

What you get

• A camera-perspective highway with notes flying down toward a virtual fretboard at the bottom of the screen
• Glowing strings that pulse and brighten on each hit
• Note Detection feedback, including hit/miss outlines and diagnostic early/late/sharp/flat labels when the note detection plugin emits enriched judgments
• Chord frame-boxes, named-chord labels, and a chord diagram overlay (configurable corner position) so you can read shapes at a glance
• Two complementary barre indicators fire together when a barre chord shape is detected (2+ consecutive strings fretted at the lowest fret, e.g. F [1,1,2,3,3,1], or an outer-edge full-span barre with every intermediate string fretted, e.g. B major x24442): a translucent vertical line across the strings on the 3D highway, and a straight bracket drawn inside the first fret space of the chord diagram overlay
• A heat-colored fret number row that lights up around your active playing region
• Selectable color palettes for the strings — pick the look you want
• Audio-reactive ambient background animations (particles, silhouettes, stage lights, geometric — pick one or turn it off)
• Lyrics overlay synced to the song
• Works as the main player view or per-panel inside the splitscreen plugin

Install

3D Highway ships bundled with FeedBack — no separate installation needed. Pick 3D Highway from the visualization picker in the player.

Note: The bundled version is preferred over any user-installed copy with the same plugin ID. If you have an old feedBack-plugin-3dhighway clone on disk (from before 3D Highway was promoted to core), it will be ignored at startup — a warning in the server log names the path of the discarded copy. You can safely delete the stale clone.

Fallback: In the unlikely event that the bundled copy fails to load its routes (e.g., a broken bundled release), FeedBack will automatically fall back to your user-installed copy and show a yellow "Fallback" badge in the Settings panel. Check the server startup log for the root cause in that case.

Settings

Most of the visual controls (background style, intensity, audio reactivity, color palette) live on FeedBack's Settings screen under the 3D Highway section.

Contributing / development

For maintainers and AI assistants working on the codebase, see CLAUDE.md — it's a navigation guide that maps every visual element to where it lives in screen.js, plus the gotchas worth knowing before tweaking.

Perf bench (?h3dbench=1)

Append ?h3dbench=1 to the player URL to enable opt-in console.log reporting of update() self-time, broken into six segments — frame (everything between pbBeg(0) at the top of update() and pbEnd(0) at the bottom; excludes the trailing pbReportTick() logging that fires after pbEnd(0)), state (per-frame state-derivation loop), next (next-note-by-string lookahead), mat (per-string material writes), noteDraw (single-note draw loop), chordDraw (chord draw loop). Reported every 5 seconds with p50 / p95 / max per segment and frame count, so before/after numbers on a target chart are reproducible (feedBack#226). Off-by-default; the bench helpers (pbBeg / pbEnd / pbReportTick) are bound to a shared empty-function literal when the renderer instance is created (each createHighway() panel re-checks the flag), so the hot-path call sites are no-ops with negligible overhead (typically JIT-inlined).