import type { Texture } from "three";
import { HemisphereLight } from "three";
export interface SkyLightOptions {
    /** Top N pixels by luminance. Default: 100. */
    skySampleCount?: number;
    /** Bottom N pixels by luminance. Default: 100. */
    groundSampleCount?: number;
    /** Default: true. */
    applyGamma?: boolean;
    /** Default: 2.2. */
    gamma?: number;
}
/**
 * Hemisphere light with HDR environment map support for automatic sky/ground color extraction.
 */
export declare class SkyLight extends HemisphereLight {
    /** @param texture - Must have image data. */
    setColorsFromHDRTexture(texture: Texture, options?: SkyLightOptions): void;
    private insertSorted;
    private averagePixels;
}