Function surfaceTween

packages/cli/src/commands/keyframes.ts:182–218

(anim: GsapAnimation)

}

function surfaceTween(anim: GsapAnimation): SurfacedTween {
  const start =
    typeof anim.resolvedStart === "number" ? anim.resolvedStart : (num(anim.position) ?? 0);
  const duration = anim.duration ?? 0;

  let shape: SurfacedTween["shape"];
  let rawKfs: Array<{ percentage: number; properties: Record<string, number | string> }>;
  if (anim.keyframes?.keyframes?.length) {
    shape = "keyframes";
    rawKfs = anim.keyframes.keyframes;
  } else if (anim.arcPath?.enabled) {
    shape = "motionPath";
    rawKfs = [];
  } else {
    shape = "flat";
    rawKfs = flatKeyframes(anim).map((k) => ({ percentage: k.pct, properties: k.properties }));
  }

  const keyframes: KeyframePoint[] = rawKfs.map((kf) => ({
    pct: kf.percentage,
    time: Math.round((start + (kf.percentage / 100) * duration) * 1000) / 1000,
    properties: cleanProps(kf.properties),
  }));

  return {
    id: anim.id,
    target: anim.targetSelector,
    method: anim.method,
    group: anim.propertyGroup,
    start: Math.round(start * 1000) / 1000,
    duration,
    end: Math.round((start + duration) * 1000) / 1000,
    shape,
    keyframes,
    path: isPositionTween(anim) ? positionPath(keyframes) : null,
  };
}

// Carry x/y forward across keyframes that only set one axis, so the path is
// continuous (GSAP holds the last value for an unspecified property).