import { BarChartOrientation, BarSegment } from "../types";
export declare function segmentKey(segment: Pick<BarSegment, "categoryIndex" | "seriesLabel">): string;
export declare function buildSegmentMap(segments: BarSegment[]): Map<string, BarSegment>;
/** CSS keyframes と reflow で共通の ease-out カーブ */
export declare const chartMotionEaseCss = "cubic-bezier(0.16, 1, 0.3, 1)";
/** 線・面の描画。棒のスナップな ease-out だと軌跡が見えない */
export declare const chartDrawEaseCss = "cubic-bezier(0.45, 0, 0.55, 1)";
/** 棒の duration より長くして、線が左から伸びる様子が見えるようにする */
export declare function getChartDrawDurationMs(motionDurationMs: number): number;
/** 初回 enter の系列/棒ごとの遅延。全体が長くなりすぎないよう cap する */
export declare function getChartEnterAnimationDelay(enterIndex: number, staggerMs: number, durationMs: number): number;
/** enter 完了後に animation を "none" へ戻すまでの待ち時間 */
export declare function getChartEnterAnimationTimeout(itemCount: number, durationMs: number, staggerMs: number): number;
/** 終端の減速を長く取る ease-out（7乗） */
export declare function easeOut(t: number): number;
export declare function lerpValue(from: number, to: number, t: number): number;
export declare function lerpSegment(from: BarSegment, to: BarSegment, t: number): BarSegment;
export declare function collapsedSegment(target: BarSegment, orientation: BarChartOrientation): BarSegment;
export declare function interpolateSegments(from: BarSegment[], to: BarSegment[], t: number, orientation: BarChartOrientation): BarSegment[];