import { Timeline } from '../timeline/timeline';
import { Sequence } from './sequence';
export declare class SequenceBuilder<T extends Timeline> {
    private latestEndTime;
    private readonly items;
    /**
     * Adds a new timeline and makes it the last of the sequence.
     * @param timeline The timeline to add.
     * @param timeOffset How early (negative) or late (positive).
     * relative to the end of the previous timeline the new one should start.
     * If this is the first timeline being added the "previous timeline" is considered
     * to start and end at t=0. Also, the new timeline will be set to start at t=0 if
     * t_endOfPrevious + timeOffset < 0.
     */
    append<Tn extends Timeline>(timeline: Tn, timeOffset?: number): SequenceBuilder<T | Tn>;
    /**
     * Builds the sequence and starts it.
     * @returns The sequence.
     */
    start(): Sequence<T>;
}