Clyune Component GalleryHeartbeat Like · How it works & code
Liked hearts pulse rhythmically — quickly zooming in and back out, like a 'thump'.
Runtime logic
Visiting `/micro/heart`, DemoHost lazy-loads `demos/kits/kit-micro.js` (registry `mod: 'kit-micro'`) and calls `mount(host, { variant: 'heart' })`. mount resolves the variant to family `heart`; `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. Pointer down/drag/move updates the interaction (drag handles, hover readouts); when untouched and auto-demo is on, the pointer follows a Lissajous path. 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.onDown — Pointer down; S.onUp — Pointer up; S.clear — Clears with the background colour (translucent = trails); S.isAutoDemo — Whether auto demo is on; S.onFrame — Registers a per-frame callback; its return value feeds the info panel; ctx.stroke() — Strokes the current path; ctx.save() — Saves the drawing state (transform, styles, clip); ctx.fill() — Fills the current path; ctx.restore() — Restores the saved drawing state; ctx.beginPath() — Starts a new path; ctx.lineTo() — Adds a straight line to a point; ctx.moveTo() — Moves the pen without drawing; ctx.arcTo() — Adds an arc using tangent lines; ctx.closePath() — Closes the current sub-path; ctx.bezierCurveTo() — Adds a cubic Bézier curve segment; ctx.fillRect() — Fills a rectangle
Source code
frontend/src/demos/kits/kit-micro.js: FAM.heart (L236-L249)
Code walkthrough
L236-249: Calls the factory `mFam()` to produce the full definition (spec + doc + build) from the options below. L236-236: Title shown in the info and control panels: “Heartbeat Like”. L236-236: Range/default of the count slider. L236-236: Extra demo-specific slider/toggle: Zoom Factor. L236-236: Range/default of the size slider. L236-236: Default main colour. L236-236: Animation period (s). L237-237: Help text of the count parameter. L237-237: Help text of the extra parameter. L237-237: Help text of the size parameter. L238-238: Preset buttons: name → parameter overrides (5). L239-239: Body of the “Notes” section. L240-240: Main formula of the “Formula” section. L240-240: Second formula line. L241-249: Per-frame draw function: draws with Canvas 2D `stroke`, `save`, `fill`, `restore`, `beginPath`, `lineTo`; math via `Math.floor`, `Math.sin`, `Math.min`, `Math.exp`, `Math.hypot`; returns readouts `mode`, `cell` to the info panel.
Principles
Scale = 1 + (multiple - 1) · Pulse (phase) Pulse (p) = sin(π · p)², p For the progress of each heartbeat Heart beats: The praised heart beats like the heart - quickly magnifying and then falling back, like "Pushing." Each beat is undergone by a pulsation that spreads out of the heart of love, while the EKG line below peaks when it beats. There's no real use here DOM 控件：每个微交互都在画布上逐帧画出来。动画按固定周期自动循环播放，并用一个「演示指针」模拟用户的点击、按住或拖动；你在画布上点一下，动画就会从头重新播放一遍。右侧滑条改动后立刻生效，下方信息面板实时显示当前状态。