import { Renderer } from "../renderer";
/**
 * Supply so the yield operator knows when to execute stuff
 */
export declare enum YieldType {
    START_OF_FRAME = 0,
    END_OF_FRAME = 1
}
/**
 * Provides the ability to delay execution of an operation/function to the different
 * parts of the Rendering Pipeline
 */
export declare class YieldQueue {
    private readonly _queueStart;
    private readonly _queueEnd;
    private readonly _renderer;
    constructor(renderer: Renderer);
    /**
     * Execute an operation at the start of the next frame
     */
    get next(): Promise<Renderer>;
    /**
     * Execute an operation at the end of the current frame
     */
    get last(): Promise<Renderer>;
    /**
     * Execute an operation at the specified point in time
     *
     * YieldType.START_OF_FRAME - executes an operation at the start of the next frame
     * YieldType.END_OF_FRAME - executes an operation at the end of the current frame
     *
     * @param yieldType - when the operation should execute
     */
    exec(yieldType?: YieldType): Promise<Renderer>;
    /**
     * Executed by the renderer at start of a frame
     */
    _flushStart(): void;
    /**
     * Executed by the renderer at end of a frame
     */
    _flushEnd(): void;
}