Particles & Physics
Verlet Rope Bridge
Amber glowing rope sags between two pegs under invisible rolling weights via Verlet physics; pointer disturbs it, clicks launch new loads.
canvasheavy complexitymoderate motionpointer
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Worth keeping?
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When to use it
Physics demo backgrounds, portfolio heroes, ambient canvases with tactile interaction.
When not to
Layouts needing legible text overlays; low-end mobile where 14-iteration constraint relaxation per frame may stutter.
Working with an AI agent
Every component ships agent-ready metadata. An example instruction for this one:
Change rope color to electric blue by setting r=72, g=194, bl=240 in the velocity-tint segment loop, and raise GRAV from 0.32 to 0.55 for heavier sag. 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
- gravity constant (GRAV=0.32)
- damping factor (DAMP=0.985)
- constraint iterations (ITER=14)
- rope color base (r=240,g=194,bl=72)
- rolling weight mass range (1.6+random*2.6)
- weight spawn interval (120+random*150)
- theme tokens (:root dark defaults + [data-theme=light] overrides)
Keep intact
- IIFE wrapper
- prefers-reduced-motion static-settle branch
- visibilitychange pause/resume
- DPR-aware canvas sizing
- theme hook (?theme= bootstrap + forever:theme message listener + theme tokens)
Known limitations
- 14 constraint-relaxation iterations per frame — CPU-bound on low-end devices
- No aria semantics on canvas element
- Background color hardcoded in CSS (#161108)
More Particles & Physics components
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- 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.