continuous-loops（连续循环）

Continuous Loop Animations

Apply Disney's 12 principles to animations that never stop.

Principle Application

Squash & Stretch: Subtle scale oscillation (0.98-1.02) creates organic breathing. Avoid rigid mechanical loops.

Anticipation: Build anticipation into the loop cycle. Brief pause at extremes before reversing.

Staging: Loops should support, not dominate. Keep amplitude subtle for background elements.

Straight Ahead vs Pose-to-Pose: Design keyframe poses that loop seamlessly. End frame must flow into start frame.

Follow Through & Overlapping: Multi-part loops have elements at different phases. Three dots pulse with 120° phase offset.

Slow In/Slow Out: Use ease-in-out for smooth oscillations. Linear motion looks mechanical.

Arcs: Circular motion follows true arcs. Spinners rotate, pendulums swing, orbits circle.

Secondary Action: Primary rotation + secondary wobble. Spinner spins while slightly bouncing.

Timing:

• Fast loops: 500-800ms (spinners, urgent indicators)
• Medium loops: 1000-2000ms (pulsing, breathing)
• Slow loops: 2000-4000ms (ambient, background)

Exaggeration: Minimal for loops - they're already attention-grabbing through repetition.

Solid Drawing: Loops must be seamless. Any jump between end and start destroys the illusion.

Appeal: Loops should be hypnotic, not annoying. Test at 30 seconds - still pleasant?

Timing Recommendations

Implementation Patterns

/* Smooth spinner */
.spinner {
  animation: spin 700ms linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* Organic pulse */
.pulse {
  animation: pulse 2000ms ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { transform: scale(1); opacity: 1; }
  50% { transform: scale(1.05); opacity: 0.8; }
}

/* Staggered dots */
.dot {
  animation: bounce 1400ms ease-in-out infinite;
}
.dot:nth-child(2) { animation-delay: 160ms; }
.dot:nth-child(3) { animation-delay: 320ms; }

Performance Rules

1. Use transform and opacity only - no layout properties
2. Add will-change: transform for loops over 1 second
3. Pause off-screen loops with Intersection Observer
4. Respect prefers-reduced-motion - reduce or stop loops

Seamless Loop Formula

For breathing/pulsing: 0%, 100% keyframes must be identical. Use alternate direction for simpler ping-pong effects.