/**
 * Smooth ViewBox Animation Utility
 *
 * Provides animated transitions between viewBox states using requestAnimationFrame.
 * Used by both story viewer and story builder for consistent smooth transitions.
 */
import type { ViewBox } from '../core/types/viewer';
import type { ViewerApi } from '../core/types/viewer-api';
type AnimationDeps = {
    now?: () => number;
    requestAnimationFrame?: (callback: FrameRequestCallback) => number;
    cancelAnimationFrame?: (handle: number) => void;
};
/**
 * Smoothly animates viewBox transition from current state to target state
 * @param viewer - Viewer API instance
 * @param targetViewBox - Target viewBox to animate to
 * @param durationMs - Animation duration in milliseconds (default: 500ms)
 * @param deps - Runtime dependencies for testing
 */
export declare const animateViewBoxTransition: (viewer: ViewerApi, targetViewBox: ViewBox, durationMs?: number, deps?: AnimationDeps) => (() => void);
/**
 * Smoothly animates layer opacities from fromOpacities to toOpacities
 * @param viewer - Viewer API instance
 * @param fromOpacities - Initial opacities map
 * @param toOpacities - Target opacities map
 * @param durationMs - Animation duration in milliseconds (default: 1000ms)
 * @param deps - Runtime dependencies for testing
 */
export declare const animateLayerOpacities: (viewer: ViewerApi, fromOpacities: Record<string, number>, toOpacities: Record<string, number>, durationMs?: number, deps?: AnimationDeps) => (() => void);
export {};