import { CameraSnapshot, CameraTour } from '@kepler.gl/types';
/** Validate imported stops and copy authored fields, omitting empty or unsafe tours. */
export declare function normalizeCameraTour(value: unknown): CameraTour | null;
export declare function getCameraTourDuration(tour: CameraTour | null | undefined): number;
/**
 * Evaluate an authored tour at elapsed milliseconds, without clocks or rendering state.
 * Holds precede travel; boundaries belong to the next stop and zero-length travel is a cut.
 * Travel uses smoothstep easing and the shortest longitude/bearing rotation (180° ties go west).
 * Time clamps to the tour; NaN means its start. The final hold contributes to duration.
 */
export declare function evaluateCameraTour(tour: CameraTour | null | undefined, elapsedMs: number): CameraSnapshot | null;