gsap-greensock（gsap 绿袜）

GSAP Animation Principles

Implement all 12 Disney animation principles using GSAP's powerful timeline and tween system.

1. Squash and Stretch

gsap.to(".ball", {
  scaleX: 1.2,
  scaleY: 0.8,
  yoyo: true,
  repeat: 1,
  duration: 0.15,
  ease: "power2.inOut"
});

2. Anticipation

const tl = gsap.timeline();
tl.to(".character", { y: 20, scaleY: 0.9, duration: 0.2 }) // wind up
  .to(".character", { y: -200, duration: 0.4, ease: "power2.out" }); // action

3. Staging

gsap.to(".background", { filter: "blur(3px)", opacity: 0.6 });
gsap.to(".hero", { scale: 1.1, zIndex: 10 });

4. Straight Ahead / Pose to Pose

// Pose to pose with explicit keyframes
gsap.to(".sprite", {
  keyframes: [
    { x: 0, y: 0 },
    { x: 100, y: -50 },
    { x: 200, y: 0 },
    { x: 300, y: -30 }
  ],
  duration: 1
});

5. Follow Through and Overlapping Action

const tl = gsap.timeline();
tl.to(".body", { x: 200, duration: 0.5 })
  .to(".hair", { x: 200, duration: 0.5 }, "-=0.4")  // overlaps
  .to(".cape", { x: 200, duration: 0.6 }, "-=0.45"); // more drag

6. Slow In and Slow Out

gsap.to(".element", {
  x: 300,
  duration: 0.6,
  ease: "power2.inOut" // slow in and out
});
// Other eases: "power3.in", "power3.out", "elastic.out"

7. Arc

gsap.to(".ball", {
  motionPath: {
    path: [{ x: 0, y: 0 }, { x: 100, y: -100 }, { x: 200, y: 0 }],
    curviness: 1.5
  },
  duration: 1
});

8. Secondary Action

const tl = gsap.timeline();
tl.to(".button", { scale: 1.1, duration: 0.2 })
  .to(".icon", { rotation: 15, duration: 0.15 }, "<") // same time
  .to(".particles", { opacity: 1, stagger: 0.05 }, "<0.1");

9. Timing

// Fast snap
gsap.to(".fast", { x: 100, duration: 0.15 });
// Gentle float
gsap.to(".slow", { y: -20, duration: 2, ease: "sine.inOut", yoyo: true, repeat: -1 });

10. Exaggeration

gsap.to(".element", {
  scale: 1.5,        // exaggerated scale
  rotation: 720,     // multiple spins
  duration: 0.8,
  ease: "back.out(2)" // overshoot
});

11. Solid Drawing

gsap.to(".box", {
  rotationX: 45,
  rotationY: 30,
  transformPerspective: 1000,
  duration: 0.5
});

12. Appeal

gsap.to(".card", {
  scale: 1.02,
  boxShadow: "0 20px 40px rgba(0,0,0,0.2)",
  duration: 0.3,
  ease: "power1.out"
});

GSAP Timeline Pattern

const masterTL = gsap.timeline({ defaults: { ease: "power2.out" }});
masterTL
  .add(anticipation())
  .add(mainAction())
  .add(followThrough());

Key GSAP Features

• gsap.timeline() - Sequence animations
• ease - 30+ built-in easing functions
• stagger - Offset multiple elements
• motionPath - Arc and path animations
• yoyo / repeat - Loop control
• "<" / "-=0.2" - Position parameter for overlap