Clyune Component GalleryNebula Sphere · How it works & code
Divide the sphere into N×N segments along meridians and parallels, placing one glowing point at each grid point to create the 'Nebula sphere'.
Runtime logic
Visiting `/threejs/nebula`, DemoHost lazy-loads `demos/kits/kit-three.js` (registry `mod: 'kit-three'`) and calls `mount(host, { variant: 'nebula' })`. mount resolves the variant to family `nebula`; `withControls` builds the control panel (6 presets + sliders). `createThreeStage` sets up WebGLRenderer, Scene, PerspectiveCamera and OrbitControls, plus 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; WebGL (three.js): WebGL through three.js WebGLRenderer; 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, three 0.170.0
Dependencies
three 0.170.0, three/addons/controls/OrbitControls.js 0.170.0, 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; createThreeStage — Shared three.js stage: WebGLRenderer, scene, perspective camera, OrbitControls, auto framing and render loop; addLights — Adds ambient + key + fill lights; THREE — three.js namespace; fmt — Number formatting (fixed decimals); deg — Radians → degrees text; F — Formula block HTML; S.get — Reads current control values; S.onFrame — Registers a per-frame callback; its return value feeds the info panel; THREE.SphereGeometry — Sphere geometry; THREE.PointsMaterial — Points material; THREE.AdditiveBlending — Additive blending (glow); THREE.Points — Point cloud; THREE.Mesh — Mesh (geometry + material); THREE.MeshBasicMaterial — Unlit material
Source code
frontend/src/demos/kits/kit-three.js: FAM.nebula (L81-L109)
Code walkthrough
L82-82: Control definitions (colour/speed/size/count/extras): Star point color, Point size, Lat/long segmentation, Breathing amplitude. L83-83: Preset buttons: name → parameter overrides (6). L84-84: 3D framing radius. L85-93: Info-panel content: live rows(v), formula, notes, params, steps. L94-108: Init function: sets up state and returns the per-frame callback: creates three.js objects `SphereGeometry`, `PointsMaterial`, `AdditiveBlending`, `Points`, `Mesh`, `MeshBasicMaterial`; math via `Math.max`, `Math.min`, `Math.round`, `Math.cos`; returns readouts `th`, `seg`, `pts`, `ps`, `rho` to the info panel.
Principles
x = ρ·sinφ·cosθ，y = ρ·cosφ，z = ρ·sinφ·sinθ ρ(t) = 1 + b · sin(1.5 · /1373 (Breathing) Cut the surface by the longitude, the latitude N×N Greg, put a light spot on each grid, and it's done“Nebula Sphere”. This is it Ball Coordinates : Angle θ (Longitude) and φ (Latitude plus radius ρ Describes the point in space. 靠近两极的点会挤在一起，因为每一圈纬线都分了同样多的点——This is the characteristic of the latitude grid. “Breathe”Let the radius change with the time sine, and the whole ball expands and shrinks.