declare class CellFadeAnimator {
    private durationMs;
    private active;
    private animationFrameId;
    private onTick;
    constructor(durationMs?: number);
    markChanged(sheetId: string, r: number, c: number): void;
    getOpacity(sheetId: string, r: number, c: number): number;
    setOnTick(repaintFn: (() => void) | null): void;
    private sweepExpired;
    private ensureTicking;
}
export declare const cellFadeAnimator: CellFadeAnimator;
export declare function markCellChanged(sheetId: string, r: number, c: number): void;
export {};