import type { Effect, Frame, Gpu, Surface } from "vgpu";
import { QualityMonitor } from "./quality.js";
import type { ShaderName } from "./registry.js";
import type { ResolvedUniforms } from "./types.js";
/**
 * Every renderer on the page shares one GPU context and one frame loop.
 *
 * That matters for a gallery: twenty canvases each calling `init()` would mean
 * twenty devices and twenty rAF callbacks. Here they are twenty passes inside
 * a single command buffer, and the loop stops entirely when nothing is
 * animating.
 */
export interface StageInstance {
    readonly surface: Surface;
    readonly effect: Effect;
    active: boolean;
    /** Set when the instance wants exactly one more frame while paused. */
    dirty: boolean;
    /**
     * Held out of the loop entirely. A source shader whose layer is still being
     * built has a binding pointing at nothing, and drawing it would fault.
     */
    blocked?: boolean;
    localTime: number;
    update(deltaTime: number): ResolvedUniforms;
    /**
     * Encoded just before this instance's own pass, into the same frame.
     *
     * A source shader draws its backdrop here, so the texture it is about to read
     * is written by an earlier pass of the same command buffer.
     */
    prepare?(frame: Frame, deltaTime: number): void;
}
export declare class Stage {
    readonly gpu: Gpu;
    /**
     * The page's adaptive-quality signals, here because the loop is here: the
     * frame rate they judge is the one loop's, and a verdict about the device
     * or the battery is a verdict for every canvas on the page.
     */
    readonly quality: QualityMonitor;
    private readonly instances;
    private handle;
    private lastTime;
    constructor(gpu: Gpu);
    add(instance: StageInstance): void;
    remove(instance: StageInstance): void;
    /** Starts the loop if anything needs drawing. Cheap to call repeatedly. */
    wake(): void;
    private hasWork;
    private sleep;
}
export declare function isWebGpuSupported(): boolean;
/** One `Gpu` per page, created on first use. */
export declare function getStage(): Promise<Stage>;
export declare function createSurface(stage: Stage, canvas: HTMLCanvasElement, dpr: readonly [number, number]): Surface;
export declare function createEffect(stage: Stage, name: ShaderName, initial: ResolvedUniforms): Effect;
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