Gantt overview

The v1 Gantt is hyper-specific by design: one concrete API, one concrete fixture (a 2026 renderer roadmap), one concrete render target. Surface stays narrow until ergonomics force change.

Pieces

flowchart TD
    Data["Gantt { range, rows, bars, people }"]:::chart
    Theme["Theme::light() + Wong palette"]:::chart
    Layout["date → x · row → y · divider dates"]:::chart
    Render["wisp::Graphics + wisp::Text + wisp::Mask"]:::wisp
    Node["wisp::scene::Node"]:::wisp

    Data --> Layout
    Theme --> Layout
    Layout --> Render
    Render --> Node

    classDef chart fill:#312e81,stroke:#6366f1,color:#e0e7ff
    classDef wisp fill:#7c2d12,stroke:#ea580c,color:#fed7aa

Pixel-spec (v1, from AUT-180)

• Canvas: 1920 × 800 px.
• Left gutter (project labels, right-aligned): 180 px.
• Header band: 60 px (30 px month strip, 30 px week strip below).
• Row height: 44 px. Bar height: 28 px (vertically centred). 6 px corner radius.
• Background: white. Alt-row tint: #fafafa.
• Week grid: #e5e5e5, 1 px. Month grid: #cccccc, 2 px. Month label sits above the week label.
• Bar fill: owner colour (Wong palette, hash-assigned). Bar text: owner name, white or black auto-chosen for contrast.

Status today

• ✅ Data structs (Gantt, Row, Bar, DateRange, PersonMap).
• ✅ Theme + Wong palette + contrast util.
• ⏳ Layout math — placeholder module today; lands in chunk 2.
• ⏳ Gantt::render(&Theme) -> SceneNode — placeholder module today; lands in chunk 3.

Subsequent chapters fill in as the rendering passes ship.

Why hyper-specific first

Per AUT-180:

This is a purely presentational composition: data goes in, a scene-graph subtree comes out. The first chart we ship is hyper-specific by design: one concrete year, one concrete team, one concrete API, so the implementation has zero degrees of freedom before we iterate on flexibility.

Generalisation (bar / line / area) happens AFTER Gantt v1 has a stable internal shape — not before.