Clyune Component GalleryAbsolute Layers · How it works & code
The elements are removed from the ordinary flow, using coordinates and z-index to determine who is on top.
Runtime logic
Visiting `/layout/layers`, DemoHost lazy-loads `demos/kits/kit-layout.js` (registry `mod: 'kit-layout'`) and calls `mount(host, { variant: 'layers' })`. mount resolves the variant to family `layers`; `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.save() — Saves the drawing state (transform, styles, clip); ctx.translate() — Translates the coordinate system; ctx.rotate() — Rotates the coordinate system; ctx.fill() — Fills the current path; ctx.stroke() — Strokes the current path; ctx.restore() — Restores the saved drawing state; ctx.fillText() — Draws filled text; ctx.beginPath() — Starts a new path; ctx.moveTo() — Moves the pen without drawing; 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.layers (L338-L383), TITLES['layers'] (L648-L648)
Code walkthrough
L340-340: Control definitions (colour/speed/size/count/extras): Emphasis color, Misalignment Amount, Layers, Layer Scaling, Slight Rotation. L341-341: Preset buttons: name → parameter overrides (6). L342-350: Info-panel content: live rows(v), formula, notes, params, steps. L351-382: Init function: sets up state and returns the per-frame callback: draws with Canvas 2D `save`, `translate`, `rotate`, `fill`, `stroke`, `restore`; math via `Math.round`, `Math.min`, `Math.pow`, `Math.sin`; returns readouts `n`, `off`, `cell`, `z`, `sc`, `ph` to the info panel. L648-648: This demo's entry in the `TITLES` table (title).
Principles
Cannot initialise Evolution's mail component lateral drawing (or z larger) layer above transform: translate / Lotate does not leave the visual layer of the file stream Card piles, badges, dialogue box masks Layer upon layer ：Element separates from normal flow, coordinates and z-index 决定谁在上。这里每层略偏移、缩放，形成一叠卡片；速度让它们轻轻错动。