import type { Canvas } from "./canvas.js";
/**
 * The amount of milliseconds your can spend in a frame, if you want to
 * reach a frame rate of 60 FPS.
 */
export declare const MS_PER_FRAME_60FPS: number;
/**
 * The signature of a function that is called to draw a frame.
 */
export type RenderLoopCallback = (delta: number, timestamp: number) => unknown;
/**
 * Configuration for a {@linkcode RenderLoop},
 */
export interface RenderLoopOptions {
    /**
     * Should the current frames per second be rendered onto the canvas
     * each frame?
     */
    drawFps: boolean;
    /**
     * Should the buffer be cleared or faded to black before each frame?
     */
    onRefresh: "clear";
}
/**
 * Conveniently provides a way to have a render loop called at
 * a constant frame rate.
 */
export declare class RenderLoop {
    #private;
    /**
     * The {@linkcode Canvas} we're rendering to.
     */
    readonly canvas: Canvas;
    /**
     * A function that we call when a new frame should be drawn.
     */
    readonly renderLoop: RenderLoopCallback;
    /**
     * The configuration that was used for this render loop.
     */
    readonly options: Readonly<Partial<RenderLoopOptions>>;
    /**
     * The time at which we drew the last frame to the offscreen buffer.
     */
    private previousTimestampDraw;
    /**
     * The ID of our {@linkcode https://developer.mozilla.org/en-US/docs/Web/API/window/requestAnimationFrame requestAnimationFrame} request.
     */
    private frameRequestId;
    /**
     * The ID of our {@linkcode https://developer.mozilla.org/en-US/docs/Web/API/setTimeout setTimeout}-based
     * offscreen rendering loop.
     */
    private drawTimeout;
    /**
     * Retrieves the amount of frames drawn to the DOM throughout the loops lifetime.
     * @returns The frame count.
     */
    get frameCounter(): number;
    /**
     * Constructs a new {@linkcode RenderLoop}.
     * @param renderLoop - The function to call when a new frame should be drawn.
     * @param canvas - The canvas we're rendering to.
     * @param options - The configuration for thie {@linkcode RenderLoop}.
     */
    constructor(renderLoop: RenderLoopCallback, canvas: Canvas, options?: Partial<RenderLoopOptions>);
    /**
     * Stop the render loop.
     */
    block(): void;
    /**
     * Start the render loop.
     */
    unblock(): void;
}