playcanvas/build/playcanvas/src/scene/graphics/light-cube.js

Open-source WebGL/WebGPU 3D engine for the web

import { Vec3 } from "../../core/math/vec3.js";
import { LIGHTTYPE_DIRECTIONAL } from "../constants.js";
const lightCubeDir = [
	new Vec3(-1, 0, 0),
	new Vec3(1, 0, 0),
	new Vec3(0, -1, 0),
	new Vec3(0, 1, 0),
	new Vec3(0, 0, -1),
	new Vec3(0, 0, 1)
];
class LightCube {
	colors = new Float32Array(6 * 3);
	update(ambientLight, lights) {
		const colors = this.colors;
		const { r, g, b } = ambientLight;
		for (let j = 0; j < 6; j++) {
			colors[j * 3] = r;
			colors[j * 3 + 1] = g;
			colors[j * 3 + 2] = b;
		}
		for (let j = 0; j < lights.length; j++) {
			const light = lights[j];
			if (light._type === LIGHTTYPE_DIRECTIONAL) {
				for (let c = 0; c < 6; c++) {
					const weight = Math.max(lightCubeDir[c].dot(light._direction), 0) * light._intensity;
					const lightColor = light._color;
					colors[c * 3] += lightColor.r * weight;
					colors[c * 3 + 1] += lightColor.g * weight;
					colors[c * 3 + 2] += lightColor.b * weight;
				}
			}
		}
	}
}
export {
	LightCube
};