import type { vec4 } from '@visactor/vutils';
import type { vec3 } from '../interface';
export declare class DirectionalLight {
    dir: vec3;
    color: string;
    colorRgb: vec4;
    formatedDir: vec3;
    ambient: number;
    constructor(dir: vec3, color: string, ambient?: number);
    computeColor(normal: vec3, color: string | vec3): string;
}
export declare const registerDirectionalLight: () => void;