∞ forever components

Particles & Physics

N-Body Waltz

Five glowing gravitational bodies orbit and sling each other in deep space, trailing colored comet tails; pointer perturbs the dance, click reseeds.

canvasheavy complexityintense motionpointer

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When to use it

Dark-mode hero backgrounds, space/science themes, generative art displays where constant motion is welcome.

When not to

Low-end devices (O(N²) physics loop per frame with 3 substeps). Any context requiring legible text overlays or light backgrounds.

Working with an AI agent

Every component ships agent-ready metadata. An example instruction for this one:

Increase body count to 7 by changing N=5 to N=7 and add two palette entries to PAL, then slow trails by reducing TLEN from 46 to 30. Theme: dark tokens live in :root, the light variant in :root[data-theme="light"]; ?theme=light or a {type:'forever:theme'} postMessage switches at runtime.

Safe to edit

  • body count (N=5)
  • gravitational constant (G=1400)
  • trail length (TLEN=46)
  • color palette (PAL array)
  • pointer repulsion strength (f=2600/d2)
  • substep count (sub=3)
  • theme tokens (:root dark defaults + [data-theme=light] overrides)

Keep intact

  • DPR-aware canvas sizing and ctx.setTransform
  • visibilitychange pause/start guard
  • reduced-motion static fallback (draw after 140 steps)
  • IIFE wrapper
  • theme hook (?theme= bootstrap + forever:theme message listener + theme tokens)

Known limitations

  • O(N²) gravity loop runs 3 substeps per frame — heavy on low-end CPUs as N grows
  • Background color hardcoded (#05060f) — must edit CSS to change from deep navy
  • Soft recentering and leash may cause subtle energy drift in long runs

physicsgravityn-bodycanvasparticlesspacegenerative

More Particles & Physics components

  • Gravity Dot RainMulticolored dots fall under gravity with motion trails, bounce off the floor, and scatter away from the cursor on a dark navy canvas.
  • Firework BurstColorful glowing sparks burst radially, fall under gravity, and fade against a dark sky. Auto-launches bursts; click anywhere to add more.
  • Confetti CannonColored rectangles fire from bottom corners in auto-cycling bursts, tumbling with gravity and flip animation. Click anywhere to trigger a cursor burst.
  • Bouncing Balls7–14 glossy pastel balls bounce off walls and collide with elastic physics; cursor repels balls within a 70px radius.
  • Spring ChainA 16-node spring chain whips and follows the cursor in a lime-to-gold gradient; drifts in a figure-eight pattern when idle.
  • Cloth Wave GridAn 11x11 wireframe grid ripples like cloth via sine/cosine waves in cyan-to-violet hues; mesh nodes bulge away from the cursor on hover.