Clyune Component GalleryGrid Layout · How it works & code
CSS Grid toy: light gradient cells.
Runtime logic
Visiting `/layout/grid`, DemoHost lazy-loads `demos/kits/kit-layout.js` (registry `mod: 'kit-layout'`) and calls `mount(host, { variant: 'grid' })`. mount resolves the variant to family `grid`; `withControls` builds the control panel (6 presets + sliders). `createCanvasStage` creates the `<canvas>` (HiDPI ≤ 2×, ResizeObserver) and the info panel. The family’s `build(S)` initialises state and returns the per-frame callback. Every `requestAnimationFrame`: read controls, advance a speed-scaled clock (dt ≤ 50 ms), run the frame callback; returned readouts go to the info panel. Changing parameters: colour/speed/size apply live; structural ones remount; leaving the page cancels rAF, removes listeners and frees resources.
Environment
Canvas 2D: 2D canvas drawing; requestAnimationFrame: Display-synced animation loop; ResizeObserver: Canvas follows container size; Pointer Events: Unified mouse/touch/pen events; devicePixelRatio: Crisp HiDPI rendering (capped at 2×) · react 18.3.1, react-router-dom 6.30.6, vite 5.4.21
Dependencies
react 18.3.1
Imported APIs
withControls — Wraps the demo in the shared control panel (presets, sliders, reset); hot-updates or remounts on change; paramsFromSpec — Turns the spec (colour/speed/size/count/extras) into control-panel parameter definitions; createCanvasStage — Shared Canvas 2D stage: canvas + info panel, HiDPI, one rAF loop, pointer state, idle auto-pointer; hueOf — Hue of a colour (0–360°); clamp — Clamps a value to a range; TAU — Constant 2π; fmt — Number formatting (fixed decimals); F — Formula block HTML; S.clear — Clears with the background colour (translucent = trails); S.onFrame — Registers a per-frame callback; its return value feeds the info panel; ctx.setLineDash() — Sets the dash pattern for strokes; ctx.beginPath() — Starts a new path; ctx.moveTo() — Moves the pen without drawing; ctx.lineTo() — Adds a straight line to a point; ctx.stroke() — Strokes the current path; ctx.fill() — Fills the current path; ctx.fillText() — Draws filled text; ctx.arcTo() — Adds an arc using tangent lines; ctx.closePath() — Closes the current sub-path; ctx.measureText() — Measures text width
Source code
frontend/src/demos/kits/kit-layout.js: FAM.grid (L45-L104), TITLES['grid'] (L647-L647)
Code walkthrough
L47-47: Control definitions (colour/speed/size/count/extras): Emphasis color, gap, Column Count, Rows, Rounded, dense packing. L48-48: Preset buttons: name → parameter overrides (6). L49-57: Info-panel content: live rows(v), formula, notes, params, steps. L58-103: Init function: sets up state and returns the per-frame callback: draws with Canvas 2D `setLineDash`, `beginPath`, `moveTo`, `lineTo`, `stroke`, `fill`; math via `Math.round`, `Math.sin`; returns readouts `cols`, `rows`, `n`, `gap`, `cell`, `area`, `dense` … to the info panel. L647-647: This demo's entry in the `TITLES` table (title).
Principles
grid-template-columns: repeat(N, 1fr) Each grid is wide = (Container wide − gap×(N−1)) / N grid-auto-flow: dense fills a small piece in the back to the front Grid 是二维布局：同时管行和列。你声明「几列几行、间隙多少」，浏览器把子元素按顺序放进格子；也可以让某个元素横跨多列（span）。 Here's the light card simulation grid entry. Other Organiser / Rows / The gap is immediately geometry; open dense It's coming up behind the big block"Fifteen"效果。指针移到格子上，右侧显示它的行列坐标。