strange-attractorz
v1.0.1
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Interactive 3D strange attractor visualization with real-time parameter control
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strange-attractorz
An interactive 3D visualization of 28 strange chaotic attractor systems — a reusable React component library built with Three.js and TypeScript. Also serves as the reference application for the original Python port vdesdm/attractors.
Table of Contents
- strange-attractorz
- Table of Contents
- Installation
- Quick Start
- Usage
- Basic setup
- [Full control example](#full-control example)
- Custom background color
- Capturing a screenshot / wallpaper
- Navigating the interface
- Interacting with the 3D scene
- What is a strange attractor?
- Features
- The 28 Attractor Systems
- System Equations Reference
- Parameters & Ranges
- API Reference
- Extending: Adding Your Own Attractor
- Architecture
- Performance
- Technical Decisions
- Acknowledgements
Installation
As an npm package
npm install strange-attractorz react react-dom
# or
pnpm add strange-attractorz react react-dom
# or
yarn add strange-attractorz react react-domRequires React 19 as a peer dependency.
import { AttractorCanvas, AttractorPanel, getSystem, systems } from "strange-attractorz";
import "strange-attractorz/styles.css";
import { useState } from "react";
export default function App() {
const [params, setParams] = useState([10, 28, 8 / 3]);
return (
<>
<AttractorCanvas
system={getSystem("lorenz")}
params={params}
/>
<AttractorPanel
system={getSystem("lorenz")}
selectedId="lorenz"
systems={systems}
params={params}
onParamChange={(i, v) => { const p = [...params]; p[i] = v; setParams(p); }}
onReset={() => { /* handle reset */ }}
/>
</>
);
}As a local project
# 1. Clone the repository
git clone https://github.com/yourusername/strange-attractors.git
cd strange-attractors
# 2. Install dependencies
pnpm install
# 3. Start the development server
pnpm devThe dev server starts on http://localhost:5173 by default. It hot-reloads on every file save — edit a system equation, save, and the browser updates instantly.
Production build
pnpm buildOutputs to dist/. Serve with any static file server:
pnpm preview # uses Vite's built-in production server
# or:
npx serve distQuick Start
- Open
http://localhost:5173 - You see a Lorenz attractor rendering — two intertwined spiral lobes, colored in a rainbow gradient
- The attractor is already being integrated — new points are added every frame
- The panel on the left shows controls
First launch
| Step | Action | Result | | --- | --- | --- | | 1 | Select a system from the dropdown | Camera reframes, trajectory resets | | 2 | Drag a parameter slider | Trajectory morphs smoothly to new shape | | 3 | Toggle auto-rotate | Camera orbits the attractor | | 4 | Click Reset | Clears point cloud, restarts from initial conditions |
Navigating the interface
System selector (top of panel): The dropdown lists all 28 systems alphabetically. Selecting a different system resets the trajectory, reframes the camera to the new system's axis limits, and clears the old point cloud.
Parameter sliders — one per ODE parameter: Each slider corresponds to a parameter in the ODE. The label shows the parameter name (e.g., "σ (sigma)"). Dragging a slider:
- Changes the ODE coefficients immediately
- The trajectory smoothly morphs from its current shape to the new one
- No discontinuity — the trajectory continues from its current point
Display controls:
- Color speed — How fast the rainbow cycles through the color wheel. Low = subtle shifts; High = vivid, rapidly-changing gradients.
- Point size — Adjusts the rendered size of each point. Larger = fuller but may obscure fine structure. Smaller = more detail but may look sparse.
- Steps per frame — How many integration steps are computed per animation frame. Low (1–50) = smooth but builds slowly. High (200–1000) = fills fast but may stutter on slow hardware.
Reset button: Clears the point cloud and restarts the simulation from the system's initial coordinates with the current parameter values.
Interacting with the 3D scene
| Gesture | Action | | --- | --- | | Left-click + drag | Rotate the camera | | Scroll wheel | Zoom in / out | | Right-click + drag | Pan the camera |
The camera uses damped orbit controls — when you release the mouse, the rotation smoothly decelerates rather than stopping instantly.
Adjusting parameters in real time
The parameter adjustment is the core interactive feature:
- You drag a slider — e.g., the Lorenz
ρ (rho)parameter from 28 to 10 - React state updates —
setParamsis called with the new array - Config object is updated — A
useEffectwrites the new params into the sharedconfigobject that the animation loop reads from - Next animation frame — The
continueIntegrate()call picks up the new parameter values - New trajectory branches — The ODE solver continues from the current trajectory point with the new equations — the result is a smooth morphing, not an abrupt jump
- Visual feedback — Newly added points trace the new attractor shape while old points retain their original colors
Try this experiment:
- Select Lorenz, let the attractor build up to ~200K points
- Slowly increase
ρ (rho)from 28 to 30 - Watch the butterfly wings spread apart
- Slowly decrease
σ (sigma)from 10 to 5 - Watch the trajectory transition from chaotic to convergent
- Click Reset to return to the canonical Lorenz shape
What is a strange attractor?
A strange attractor is a set of values (a trajectory) toward which a dynamical system evolves, in a state space whose geometry is fractal. The systems studied here are defined by ordinary differential equations (ODEs) — systems of first-order equations of the form:
dx/dt = f(x, y, z, params)
dy/dt = g(x, y, z, params)
dz/dt = h(x, y, z, params)where x, y, z are the three state variables (coordinates in 3D phase space) and params is a vector of real-valued constants specific to each system.
When you start a simulation from a point near the attractor, the trajectory spirals and folds in a way that never repeats and never settles — it chaotically wanders within a bounded region. The result is a shape that looks like a cosmic sculpture.
The best-known example is the Lorenz attractor, discovered by Edward Lorenz in 1963 while studying atmospheric convection. It is the system that popularized the term "butterfly effect."
Features
| Feature | Details |
| --- | --- |
| 28 systems | Lorenz, Rössler, Chen, Thomas, Halvorsen, Nose-Hoover, Sakarya, Burke-Shaw, Rucklidge, Moore-Spiegel, Dequan Li, Langford, Dadras, Hadley, Chen-Lee, Shimizu-Morioka, Chen-Lu, Yu-Wang, Wang-Sun, Finance, Lotka-Volterra, Bouali Type 1/2/3, Newton-Leipnik, Rikitake, Rabinovich-Fabrikant, Three-Cell-CNN |
| Real-time RK4 integration | Fourth-order Runge-Kutta with O(dt⁵) local error |
| Custom GLSL shaders | Soft-edged circular points, per-point size attenuation, additive blending, HSL color mapping |
| Orbit camera | Mouse drag to rotate, scroll to zoom, right-drag to pan — Three.js OrbitControls |
| Auto-rotate | Toggle smooth 360° camera orbiting |
| 26+ parameter sliders | Every attractor exposes its parameters as sliders with min/max bounds; changing a slider immediately changes the trajectory |
| Configurable rendering | Steps per frame (speed vs. smoothness tradeoff), color speed (rainbow cycle rate), point size |
| Reset | Instantly restarts the trajectory from the system's initial conditions |
| Fully typed | Zero any — TypeScript enforces correctness across the entire codebase |
| No build-time framework overhead | Vite + React (no Next.js, no R3F) — lean bundle, instant dev server |
The 28 Attractor Systems
Each system is a tuple (name, equations, parameters, initial state) — and they fall into several families:
Classic / Foundational
| System | Year | Equations (default params) | Visual Character |
| --- | --- | --- | --- |
| Lorenz | 1963 | dx = σ(y-x), dy = x(ρ-z)-y, dz = xy-βz | Two-lobed "butterfly" |
| Rössler | 1976 | dx = -(y+z), dy = x+ay, dz = b+z(x-c) | Single-loop tapestry |
| Chen | 1999 | dx = a(y-x), dy = (c-a)x-xz+cy, dz = xy-bz | Twin-scroll, like Lorenz but topologically different |
| Thomas | 1999 | dx = sin(y)-bx, dy = sin(z)-by, dz = sin(x)-bz | Symmetric toroidal knot |
Physical / Thermodynamic
| System | Year | Equations (default params) | Visual Character |
| --- | --- | --- | --- |
| Halvorsen | 2002 | dx = -ax-4y-4z-y², dy = -ay-4z-4x-z², dz = -az-4x-4y-x² | Spherical symmetric cluster |
| Nose-Hoover | 1989 | dx = ay, dy = -x+yz, dz = 1-y² | Curving double-wing |
Engineering / Electronics
| System | Year | Equations (default params) | Visual Character |
| --- | --- | --- | --- |
| Burke-Shaw | 1981 | dx = -s(x+y), dy = -y-sxz, dz = sxy+v | Compact double-scroll |
| Sakarya | 2008 | dx = -x+y+yz, dy = -x-y+axy, dz = z-bxy | Twisted loop |
| Moore-Spiegel | 1978 | dx = y, dy = z, dz = -z-(t-r(1-x²))z-tx | Chaotic oscillator |
| Rikitake | 1958 | dx = -αx-zy+βz², dy = -βz², dz = y-ξz | Dynamo model |
| Three-Cell-CNN | 2003 | dx = a(y-h(x)), dy = x-y+z, dz = -by-cx+d(x+2y-x(z)) | Cellular network chaos |
Mathematical Curiosities
| System | Year | Equations (default params) | Visual Character |
| --- | --- | --- | --- |
| Rucklidge | 1992 | dx = -kx+αy-yz, dy = x, dz = -z+y² | Double convection model; four-wing patterns at k=2, α=6.7 |
| Langford | 1979 | dx = (z-β)x-ωy, dy = ωx+(z-β)y, dz = λ+αz-z³/3-(x²+y²)(1+ρz)+εzx³ | Complex multi-wing |
| Dequan Li | 2008 | dx = a(y-x)+dxz, dy = kx+fy-xz, dz = cz+xy-ex² | Six-scroll chaotic attractor; six parameters |
| Shimizu-Morioka | 1980 | dx = y, dy = x-ax-xz, dz = -βz+x² | Bifurcation of symmetric limit cycle |
Economic / Financial
| System | Year | Equations (default params) | Visual Character |
| --- | --- | --- | --- |
| Finance | 2007 | dx = (1/β-α)xy+z, dy = -by-x², dz = -x-cz | Financial chaos model |
| Lotka-Volterra | 1999 | dx = x-xy+cx²-azx², dy = -y+xy, dz = -bz+azx² | Predator-prey extension |
Four-Wing / Multi-Wing Attractors
| System | Year | Notes |
| --- | --- | --- |
| Yu-Wang | 2012 | "Fully qualified four-wing type"; uses exp(x·y) nonlinearity |
| Wang-Sun | 2009 | Three-dimensional four-wing attractor |
Parameter Space Surprises
| System | Year | Notes |
| --- | --- | --- |
| Dadras | 2009 | dx = y-ax+byz, dy = cy-xz+z, dz = dxy-hz — generates two, three, and four-scroll attractors depending on parameters |
| Hadley | 2013 | dx = -y²-z²-a(x-f), dy = xy-bxz-y+g, dz = bxy+(x-1)z — multi-wing convection |
| Chen-Lee | 2004 | dx = ax-yz, dy = by+xz, dz = cz+xy/3 — anti-control of chaos in rigid body motion |
| Chen-Lu | 2002 | dx = a(y-x), dy = -xz+cy, dz = xy-bz — a "new" chaotic attractor between Lorenz and Chen |
| Bouali Type 1/2/3 | 2013 | Circuit-based chaotic oscillators with different feedback configurations |
| Newton-Leipnik | 1988 | dx = (ay-ux)/(1-y²), dy = (ax+uy)/(1-y²) — double-scroll oscillator |
| Rabinovich-Fabrikant | 1979 | Classic model of nonlinear waves in active media |
System Equations Reference
Below are the complete ODEs for every system. Each equation is dx/dt = ..., dy/dt = ..., dz/dt = ....
Lorenz:
dx/dt = σ · (y - x)
dy/dt = x · (ρ - z) - y
dz/dt = x · y - β · zRössler:
dx/dt = -(y + z)
dy/dt = x + a · y
dz/dt = b + z · (x - c)Chen:
dx/dt = a · (y - x)
dy/dt = (c - a) · x - x · z + c · y
dz/dt = x · y - b · zThomas:
dx/dt = sin(y) - b · x
dy/dt = sin(z) - b · y
dz/dt = sin(x) - b · zHalvorsen:
dx/dt = -a · x - 4y - 4z - y²
dy/dt = -a · y - 4z - 4x - z²
dz/dt = -a · z - 4x - 4y - x²Nose-Hoover:
dx/dt = a · y
dy/dt = -x + y · z
dz/dt = 1 - y²Sakarya:
dx/dt = -x + y + y · z
dy/dt = -x - y + a · x · z
dz/dt = z - b · x · yBurke-Shaw:
dx/dt = -s · (x + y)
dy/dt = -y - s · x · z
dz/dt = s · x · y + vRucklidge:
dx/dt = -k · x + α · y - y · z
dy/dt = x
dz/dt = -z + y²Moore-Spiegel:
dx/dt = y
dy/dt = z
dz/dt = -z - (t - r · (1 - x²)) · y - t · xDequan Li:
dx/dt = a · (y - x) + d · x · z
dy/dt = k · x + f · y - x · z
dz/dt = c · z + x · y - e · x²Langford:
dx/dt = (z - β) · x - ω · y
dy/dt = ω · x + (z - β) · y
dz/dt = λ + α · z - z³/3 - (x² + y²) · (1 + ρ · z) + ε · z · x³Dadras:
dx/dt = y - a · x + b · y · z
dy/dt = c · y - x · z + z
dz/dt = d · x · y - h · zHadley:
dx/dt = -y² - z² - a · (x - f)
dy/dt = x · y - b · x · z - y + g
dz/dt = b · x · y + z · (x - 1)Chen-Lee:
dx/dt = a · x - y · z
dy/dt = b · y + x · z
dz/dt = c · z + x · y / 3Shimizu-Morioka:
dx/dt = y
dy/dt = x - a · y - x · z
dz/dt = -B · z + x²Chen-Lu:
dx/dt = a · (y - x)
dy/dt = -x · z + b · y
dz/dt = x · y - c · zYu-Wang:
dx/dt = a · (y - x)
dy/dt = b · x - c · x · z
dz/dt = exp(x · y) - d · zWang-Sun:
dx/dt = a · x + c · y · z
dy/dt = b · x + d · y - x · z
dz/dt = e · z + f · x · yFinance:
dx/dt = (1/b - a) · x + x · y + z
dy/dt = -b · y - x²
dz/dt = -x - c · zLotka-Volterra:
dx/dt = x - x·y + c·x² - a·z·x²
dy/dt = -y + x·y
dz/dt = -b·z + a·z·x²Bouali Type 1:
dx/dt = -a · x + a · (y - z)
dy/dt = -x - y + d · y · z
dz/dt = -b · z + x · yBouali Type 2:
dx/dt = a · (y - x)
dy/dt = c · x - x · z
dz/dt = x · y - b · zBouali Type 3:
dx/dt = -a · x + y - z
dy/dt = x + b · y - z
dz/dt = -y - c · zNewton-Leipnik:
dx/dt = (a · y - u · x) / (1 - y²)
dy/dt = (a · x + u · y) / (1 - y²)Rabitnovich-Fabrikant:
dx/dt = y · (z - 1 + x²) + γ · z
dy/dt = z · (bx - y + z)
dz/dt = x · (y - xz - 1)Three-Cell-CNN:
dx/dt = a · (y - h(x))
dy/dt = x - y + z
dz/dt = -b · y - c · x + d · (x + 2y - x(z))Parameters & Ranges
| System | Parameters | Default Values | Min | Max | | --- | --- | --- | --- | --- | | Lorenz | σ, ρ, β | 10, 28, 8/3 | 0–50 | 0–100 | | Rössler | a, b, c | 0.2, 0.2, 5.7 | -10–10 | -10–10 | | Chen | a, b, c | 35, 3, 28 | 0–50 | 0–50 | | Thomas | b | 0.2081 | 0 | 2 | | Halvorsen | a | 0.2 | 0 | 5 | | Nose-Hoover | a | 0.5 | 0 | 10 | | Burke-Shaw | s, v | 20, 10 | 0–50 | 0–50 | | Rucklidge | k, α | 2, 6.7 | 0–10 | 0–10 | | Sakarya | a, b | 2, 2 | 0–10 | 0–10 | | Moore-Spiegel | r, t | 1.5, 0.6 | 0–5 | 0–5 | | Dequan Li | a, d, k, f, c, e | 1, 1.2, 0.3, 1.8, 1.2, 0.5 | -20–20 | -20–20 | | Langford | β, ω, λ, α, ρ, ε | 0.5, 0.8, 1.8, 0.2, 0, 0.02 | Vary by param | Vary by param | | Dadras | a, b, c, d, h | 1.6, 1.6, 2.7, 2.7, 1.45 | 0–10 | 0–10 | | Hadley | a, b, f, g | 2, 2, 10, 10 | 0–20 | 0–20 | | Chen-Lee | a, b, c | 1, 3, -3.1 | -10–10 | -10–10 | | Shimizu-Morioka | a, B | 1, 14 | 0–20 | 0–20 | | Chen-Lu | a, b, c | 10, 2.5, 1.5 | 0–50 | 0–50 | | Yu-Wang | a, b, c, d | 1, 2, 0.1, 1 | -10–10 | -10–10 | | Wang-Sun | a, b, c, d, e, f | 4, 6, 4, 5, -2, 1 | -20–20 | -20–20 | | Finance | a, b, c | 0.1, 1, 1 | 0–1 | 0–1 | | Lotka-Volterra | a, c, b | 1, 0.2, 0.4 | 0–5 | 0–5 | | Bouali Type 1 | a, b, d, f | 5, 0.05, 0.02, 1 | 0–10 | 0–10 | | Bouali Type 2 | a, b, c | 5, 1, 5 | 0–10 | 0–10 | | Bouali Type 3 | a, b, c | 5, 1, 20 | 0–50 | 0–50 | | Newton-Leipnik | a, u | 0.375, 0.25 | 0–1 | 0–1 | | Rikitake | α, β, ξ | 1.5, 2, 0.6 | 0–10 | 0–10 | | Rabinovich-Fabrikant | a, b, γ | 1, 1.1, -1.1 | -5–5 | -5–5 | | Three-Cell-CNN | a, b, c, d | 2, 1, 1, 1.25 | 0–5 | 0–5 |
Architecture
Data layer: src/systems.ts
The single source of truth. Each attractor system is a typed object:
interface AttractorSystem {
id: string; // e.g. "lorenz"
name: string; // e.g. "Lorenz (1963)"
equation: EqFn; // (x, y, z, params) => [dx, dy, dz]
params: {
defaults: number[]; // e.g. [10, 28, 8/3]
names: string[]; // e.g. ["σ (sigma)", "ρ (rho)", "β (beta)"]
min: number[]; // Slider minimums
max: number[]; // Slider maximums
};
initCoord: [number, number, number];
limits?: { xlim?: [number, number]; ylim?: [number, number]; zlim?: [number, number] };
}- ~650 lines — all 28 system definitions, equation functions, type definitions, and the
systemsarray EqFnis a function type:(x: number, y: number, z: number, params: number[]) => [number, number, number]- The
wrap()function converts a rawEqFninto the expected equation signature, binding the parameter vector - The
systemsarray is exported as a const, providing both the full list and the type inference for the UI
Integration engine: src/integrate.ts
Two core functions:
integrate(system, steps, dt, paramsOverride?)
Computes the initial trajectory from scratch using RK4 (Runge-Kutta 4th order).
- Input: system definition, number of steps (typically 50,000 for initial render), time step (always 0.005), optional parameter override
- Output:
Float32Arrayof lengthsteps × 3, flat-encoded as[x₀, y₀, z₀, x₁, y₁, z₁, ...]
continueIntegrate(system, lastState, steps, dt, paramsOverride?)
Resumes integration from a given state — used for the animation loop.
- Input: system, last state
[x, y, z], number of steps, time step, optional parameters - Output:
{ data: Float32Array, lastState: [number, number, number] }
Rendering pipeline: src/components/AttractorCanvas.tsx
The most complex component (~200 lines). Manages the entire Three.js lifecycle:
- Initialization: Creates
WebGLRenderer,PerspectiveCamera,Scene - Buffer allocation: 20 MB of GPU memory — 6 MB positions + 6 MB colors + 8 MB sizes for up to 2M points
- Shader pipeline: Custom vertex + fragment shaders for soft-edged circular points with depth attenuation
- Animation loop:
requestAnimationFrame→ integrate → update buffer attributes → render - OrbitControls: Damped rotation, scroll-to-zoom, right-drag-to-pan
- Resize handling:
ResizeObserverupdates renderer and camera on window resize - Cleanup: Disposes all Three.js resources on unmount
Custom GLSL Shaders:
// Vertex shader (key lines)
gl_PointSize = aSize * (300.0 / vDepth); // Depth-attenuated point size
gl_Position = projectionMatrix * modelViewMatrix * vec4(aPosition, 1.0);
// Fragment shader (key lines)
vec4 texColor = texture2D(t2D, vec2(dot(co, vec2(0.25, 0.75)) * 2.0, 0.5));
if (texColor.a < 0.1) discard; // Discard transparent pixels
gl_FragColor = vec4(mix(vec3(0.0), texColor.rgb, aColor), 1.0);UI layer: src/components/AttractorPanel.tsx
The floating control panel. Key sections:
- System selector — dropdown populated from
systemsarray - Parameter sliders — auto-generated from
system.params, one per parameter - Display controls — steps per frame, color speed, point size, auto-rotate
- Reset button — triggers trajectory restart
Styling: Frosted glass panel: rgba(10, 10, 20, 0.85) with backdrop-filter: blur(12px). Width: 280px, positioned absolute at top-left.
API Reference
<AttractorCanvas>
The 3D rendering component. Renders the attractor trajectory as a point cloud in a Three.js WebGL context.
| Prop | Type | Default | Description |
| --- | --- | --- | --- |
| system | AttractorSystem | — | The attractor system to render |
| params | number[] | system.params.defaults | Parameter values for the ODE |
| stepsPerFrame | number | 50 | Integration steps computed per animation frame |
| colorSpeed | number | 1 | Rainbow color cycle speed multiplier |
| pointSize | number | 1.5 | Base size of rendered points (subject to depth attenuation) |
| speed | number | 0.5 | Simulation speed multiplier |
| autoRotate | boolean | true | Whether the camera auto-orbits |
| resetKey | number | 0 | Increment to trigger a reset |
| backgroundColor | string | '#000000' | Canvas background color |
| onSceneReady | (data: SceneData) => void | — | Callback with { camera, renderer, scene } for screenshots |
Internal behavior:
- Allocates 20 MB of GPU memory (6 MB positions + 6 MB colors + 8 MB sizes for 2M points)
- Uses
ResizeObserverfor responsive layout - Runs
requestAnimationFramefor the render loop - Disposes all Three.js resources on unmount
- Maximum point count: 2,000,000 (hard cap — draw range caps at this)
<AttractorPanel>
The floating control panel. Provides the UI for all configuration.
| Prop | Type | Description |
| --- | --- | --- |
| system | AttractorSystem | Current attractor system |
| selectedId | string | Currently selected system ID |
| systems | AttractorSystem[] | All available systems (for the dropdown) |
| params | number[] | Current parameter values |
| stepsPerFrame | number | Current integration speed |
| colorSpeed | number | Current color speed |
| pointSize | number | Current point size |
| speed | number | Current simulation speed |
| autoRotate | boolean | Current auto-rotate state |
| backgroundColor | string | Current background color |
| resetAfter | number | Auto-reset after N ms (0 = disabled) |
| mobileOpen | boolean | Mobile panel visibility |
| onStepsChange | (value: number) => void | Callback for steps per frame slider |
| onColorSpeedChange | (value: number) => void | Callback for color speed slider |
| onPointSizeChange | (value: number) => void | Callback for point size slider |
| onSpeedChange | (value: number) => void | Callback for speed slider |
| onAutoRotateChange | (value: boolean) => void | Callback for auto-rotate checkbox |
| onBackgroundColorChange | (value: string) => void | Callback for background color |
| onReset | () => void | Callback for reset button |
| onResetAfterChange | (value: number) => void | Callback for auto-reset timer |
| onSystemChange | (id: string) => void | Callback when system is changed |
| onParamChange | (index: number, value: number) => void | Callback when a parameter slider changes |
| onShare | () => void | Callback for share dialog |
| onWallpaperDownload | () => void | Callback for wallpaper download |
| onCloseMobile | () => void | Close mobile panel |
Utility Exports
| Export | Signature | Description |
| --- | --- | --- |
| getSystem | (id: string) => AttractorSystem \| undefined | Looks up a system by ID |
| systems | AttractorSystem[] | Complete array of 28 AttractorSystem objects |
AttractorSystem Type
interface AttractorSystem {
id: string; // e.g. "lorenz"
name: string; // e.g. "Lorenz (1963)"
equation: (state: Vector3, params: number[]) => Vector3;
params: {
defaults: number[]; // e.g. [10, 28, 8/3]
names: string[]; // e.g. ["σ (sigma)", "ρ (rho)", "β (beta)"]
min: number[]; // Slider minimums
max: number[]; // Slider maximums
};
initCoord: [number, number, number]; // e.g. [0, 1, 0]
limits?: {
xlim?: [number, number];
ylim?: [number, number];
zlim?: [number, number];
};
}Extending: Adding Your Own Attractor
To add a new attractor system:
1. Define the equation function in src/systems.ts:
const myAttractor: EqFn = (x, y, z, p) => [
p[0] * y - p[1] * x * z, // dx/dt
x * z - p[2] * y, // dy/dt
p[3] * x * y - p[4] * z, // dz/dt
];2. Register the system in the systems array:
{
id: "my_attractor",
name: "My Attractor (2024)",
equation: wrap(myAttractor),
params: {
defaults: [1, 2, 3, 4, 5],
names: ["a", "b", "c", "d", "e"],
min: [-10, -10, -10, -10, -10],
max: [10, 10, 10, 10, 10],
},
initCoord: [0.1, 0.1, 0.1],
limits: {
xlim: [-5, 5],
ylim: [-5, 5],
zlim: [-5, 5],
},
},3. Save and refresh — the new system appears in the dropdown automatically. No other changes needed.
That's it. The wrap() function and the systems array handle the rest: registration, type-checking, slider generation, and rendering.
Performance
| Metric | Value |
| --- | --- |
| Initial render time | ~50ms (50K steps + GPU buffer upload) |
| Memory usage | ~20 MB for 2M points (positions + colors + sizes) |
| GPU memory | ~44 MB (Float32Arrays + BufferGeometry) |
| Max points | 2,000,000 (hard cap — draw range caps at this) |
| Animation frame cost | ~0.5–5ms depending on stepsPerFrame |
| Bundle size (prod) | ~342 KB JS (ESM) + ~209 KB JS (CJS) |
Tuning for performance
If the animation is choppy:
- Lower
stepsPerFrame(try 10–20) — reduces per-frame integration load - Lower
pointSizeslightly — reduces GPU rasterization cost - Close other GPU-heavy applications — the canvas is a WebGL context
If you want a denser/more detailed attractor:
- Raise
stepsPerFrame(try 200–500) — the attractor builds faster - Wait for it to fill — the point cloud grows up to 2M points over time
- The color gradient will become more continuous at higher point counts
If the attractor looks sparse:
- The trajectory may be building slowly — increase
stepsPerFrame - Or the system may genuinely have a sparse attractor — try switching systems to compare
Hardware recommendations
| Platform | Minimum | Recommended | | --- | --- | --- | | GPU | Integrated graphics (Intel HD 630) | Dedicated GPU (NVIDIA GTX 1060+) | | RAM | 4 GB | 8 GB+ | | CPU | Any x86_64 | Any modern CPU (integration is single-threaded) |
Technical Decisions
Why raw Three.js instead of React Three Fiber? React Three Fiber adds ~100 KB to the bundle and an extra abstraction layer. For this project — a single full-screen canvas with no complex scene hierarchy — raw Three.js is simpler, faster, and gives more control over the shader pipeline.
Why custom GLSL shaders?
The default Points material renders square pixels. Custom shaders let us:
- Render soft-edged circles (fragment shader checks distance from point center)
- Depth-attenuate point sizes (vertex shader divides by camera distance)
- Use additive blending for the characteristic "glowing" attractor look
- Control per-point color with a custom
aColorattribute
Why a mutable shared config object instead of React state for the animation loop?
The animation loop runs at requestAnimationFrame speed (~60fps), independent of React's render cycle. Using a mutable object with known fields is simpler and more efficient than React state updates (which trigger re-renders). The animation loop reads from config directly on each frame.
Why RK4 instead of Euler?
Euler integration (xₙ₊₁ = xₙ + f(xₙ) · dt) accumulates error rapidly and can send the trajectory spiraling off to infinity even when the true solution is bounded. RK4 gives O(dt⁵) local error, keeping trajectories accurate even with dt = 0.005. For chaotic systems — which are extremely sensitive to initial conditions — numerical accuracy is critical.
Why JavaScript instead of WebAssembly? The attractor systems are simple ODEs — no complex linear algebra, no matrix operations. The per-step cost is a handful of multiply-add operations. JavaScript V8 (Chrome/Edge) or SpiderMonkey (Firefox) handles this easily at 60fps. WebAssembly would add build complexity for negligible gain.
Why HSL for color mapping? HSL gives a smooth, predictable rainbow that covers the full color spectrum. Converting from HSL to RGB in JavaScript per-frame is cheap (~10 operations). Alternative approaches — mapping by position (coloring by x, y, or z coordinate), or by velocity magnitude — also work but HSL produces the most visually striking result.
Acknowledgements
Mathematical models ported from vdesdm/attractors by vdesdm.
Numerical integration method: Classical 4th-order Runge-Kutta (Leo Fox & George B. Dantzig, 1927).
Inspired by the beautiful work of:
- Edward Lorenz (1963) — deterministic nonperiodic flow
- Otto Rössler (1976) — continuous chaos
- Guanrong Chen (1999) — the Chen attractor
- J.C. Sprott — Chaos and Time Series Analysis (2003)
Rendering built with:
- Three.js — threejs.org
- Vite — vitejs.dev
- React 19 — react.dev
- TypeScript — typescriptlang.org
