三.js：如何正确添加envMap？

Question

我正在寻找像这样的材料： https ://thirdjs.org/examples/#webgl_materials_envmaps_exr

所以我会这样尝试：

* {
margin: 0;
padding: 0;
}

.object {
position: fixed;
top: 0;
left: 0;
width: 100vw;
height: 100vh;
pointer-events: none;
background-color: rgb(200, 200, 200);
}

<script type="module">
import * as THREE from "https://threejs.org/build/three.module.js";

import { OBJLoader } from "https://threejs.org/examples/jsm/loaders/OBJLoader.js";

var container;

var camera, scene, renderer;

var mouseX = 0,
    mouseY = 0;

var windowHalfX = window.innerWidth / 2;
var windowHalfY = window.innerHeight / 2;

var object;

init();
animate();

function init() {
    container = document.createElement("div");
    container.className = "object";
    document.body.appendChild(container);

    camera = new THREE.PerspectiveCamera(
        45,
        window.innerWidth / window.innerHeight,
        1,
        2000
    );
    camera.position.z = 250;

    // scene

    scene = new THREE.Scene();

    var ambientLight = new THREE.AmbientLight(0xcccccc, 0.4);
    scene.add(ambientLight);

    var pointLight = new THREE.PointLight(0xffffff, 2);
    pointLight.position.set(100, 100, 50);

    camera.add(pointLight);
    scene.add(camera);

    // manager

    function loadModel() {
        object.traverse(function (child) {
            //This allow us to check if the children is an instance of the Mesh constructor
            if (child instanceof THREE.Mesh) {
                child.material = new THREE.MeshStandardMaterial({
                    color: "#555",
                    roughness: 0.1,
                    metalness: 0.4
                });
                child.material.flatShading = false;

                //Sometimes there are some vertex normals missing in the .obj files, ThreeJs will compute them
            }
        });
        object.position.y = -90;
        scene.add(object);
    }

    var manager = new THREE.LoadingManager(loadModel);

    manager.onProgress = function (item, loaded, total) {
        console.log(item, loaded, total);
    };

    // model

    function onProgress(xhr) {
        if (xhr.lengthComputable) {
            var percentComplete = (xhr.loaded / xhr.total) * 100;
            console.log("model " + Math.round(percentComplete, 2) + "% downloaded");
        }
    }

    function onError() {}

    var loader = new OBJLoader(manager);

    loader.load(
        "https://threejs.org/examples/models/obj/female02/female02.obj",
        function (obj) {
            object = obj;
        },
        onProgress,
        onError
    );

    //

    renderer = new THREE.WebGLRenderer({ alpha: true });
    renderer.setPixelRatio(window.devicePixelRatio);
    renderer.setSize(window.innerWidth, window.innerHeight);
    container.appendChild(renderer.domElement);

    document.addEventListener("mousemove", onDocumentMouseMove, false);

    //

    window.addEventListener("resize", onWindowResize, false);
}

function onWindowResize() {
    windowHalfX = window.innerWidth / 2;
    windowHalfY = window.innerHeight / 2;

    camera.aspect = window.innerWidth / window.innerHeight;
    camera.updateProjectionMatrix();

    renderer.setSize(window.innerWidth, window.innerHeight);
}

function onDocumentMouseMove(event) {
    mouseX = (event.clientX - windowHalfX) / 2;
    mouseY = (event.clientY - windowHalfY) / 2;
}

//

function animate() {
    requestAnimationFrame(animate);
    render();
}

function render() {
    camera.position.x += (mouseX - camera.position.x) * 0.05;
    camera.position.y += (-mouseY - camera.position.y) * 0.05;

    camera.lookAt(scene.position);

    renderer.render(scene, camera);
}
</script>

不幸的是，它不起作用。为什么？

如果有人能帮助我，我将非常感激！:)

Answer 1

主要问题是newEnvMap加载对象时尚未准备好。

一般来说，将环境贴图添加到场景的主要步骤是：

1. 进口EXRLoader。
2. 使用 . 创建“预过滤、Mipmaped 辐射环境贴图 (PMREM)” THREE.PMREMGenerator。
3. new EXRLoader()使用（或使用）加载 EXR（或 JPG 图像）THREE.TextureLoader().load()。
4. 加载 EXR 后，必须使用此设置更新对象。在 CodePen 中，这是通过函数 完成的loadObjectAndAndEnvMap()。此函数加载模型并envMap使用进行更新object.material.envMap = newEnvMap;。
5. 别忘了object.material.needsUpdate = true。
6. 最后，如果你想可视化背景本身，需要在函数scene.background = background;内部设置render。
7. （额外）如果环境贴图仍然不可见，请检查材质的roughness、metalness和。envMapIntensity设置不反映环境的值是一个常见的错误。以下是一些设置示例：

演示：

* {
margin: 0;
padding: 0;
}

.object {
position: fixed;
top: 0;
left: 0;
width: 100vw;
height: 100vh;
pointer-events: none;
background-color: rgb(200, 200, 200);
}

<script type="module">
import * as THREE from "https://threejs.org/build/three.module.js";
import { OBJLoader } from "https://threejs.org/examples/jsm/loaders/OBJLoader.js";
import { EXRLoader } from "https://threejs.org/examples/jsm/loaders/EXRLoader.js";

var container;
var camera, scene, renderer;
let exrCubeRenderTarget, exrBackground;
let newEnvMap;
let torusMesh, planeMesh;

var mouseX = 0,
    mouseY = 0;

var windowHalfX = window.innerWidth / 2;
var windowHalfY = window.innerHeight / 2;

var object;

init();
animate();

function init() {
    container = document.createElement("div");
    container.className = "object";
    document.body.appendChild(container);

    camera = new THREE.PerspectiveCamera(
        45,
        window.innerWidth / window.innerHeight,
        1,
        2000
    );
    camera.position.z = 250;

    // scene

    scene = new THREE.Scene();

    /*var ambientLight = new THREE.AmbientLight(0xcccccc, 0.4);
    scene.add(ambientLight);
    var pointLight = new THREE.PointLight(0xffffff, 2);
    pointLight.position.set(100, 100, 50);
    camera.add(pointLight);*/

    scene.add(camera);

    // manager
    function loadModel() {
        THREE.DefaultLoadingManager.onLoad = function () {
            pmremGenerator.dispose();
        };

        // -----------------

        function loadObjectAndAndEnvMap() {
            object.traverse(function (child) {
                //This allow us to check if the children is an instance of the Mesh constructor
                if (child instanceof THREE.Mesh) {
                    child.material = new THREE.MeshStandardMaterial({
                        color: "#555",
                        roughness: 0.0,
                        metalness: 2.0,
                        envMapIntensity: 5.0
                    });
                    //child.material.flatShading = false;

                    console.log("setting envmap");
                    child.material.envMap = newEnvMap;
                    child.material.needsUpdate = true;

                    //Sometimes there are some vertex normals missing in the .obj files, ThreeJs will compute them
                }
            });
            object.position.y = -90;
            scene.add(object);
        }

        const pmremGenerator = new THREE.PMREMGenerator(renderer);
        pmremGenerator.compileEquirectangularShader();

        new EXRLoader()
            .setDataType(THREE.UnsignedByteType)
            .load(
                "https://threejs.org/examples/textures/piz_compressed.exr",
                function (texture) {
                    exrCubeRenderTarget = pmremGenerator.fromEquirectangular(texture);
                    exrBackground = exrCubeRenderTarget.texture;
                    newEnvMap = exrCubeRenderTarget ? exrCubeRenderTarget.texture : null;

                    loadObjectAndAndEnvMap(); // Add envmap once the texture has been loaded

                    texture.dispose();
                }
            );

        renderer.toneMapping = THREE.ACESFilmicToneMapping;
        renderer.outputEncoding = THREE.sRGBEncoding;
    }

    var manager = new THREE.LoadingManager(loadModel);

    manager.onProgress = function (item, loaded, total) {
        console.log(item, loaded, total);
    };

    // model
    function onProgress(xhr) {
        if (xhr.lengthComputable) {
            var percentComplete = (xhr.loaded / xhr.total) * 100;
            console.log("model " + Math.round(percentComplete, 2) + "% downloaded");
        }
    }
    function onError() {}
    var loader = new OBJLoader(manager);
    loader.load(
        "https://threejs.org/examples/models/obj/female02/female02.obj",
        function (obj) {
            object = obj;
        },
        onProgress,
        onError
    );

    //

    renderer = new THREE.WebGLRenderer({ alpha: true });
    renderer.setPixelRatio(window.devicePixelRatio);
    renderer.setSize(window.innerWidth, window.innerHeight);
    container.appendChild(renderer.domElement);

    document.addEventListener("mousemove", onDocumentMouseMove, false);

    //

    window.addEventListener("resize", onWindowResize, false);
}

function onWindowResize() {
    windowHalfX = window.innerWidth / 2;
    windowHalfY = window.innerHeight / 2;

    camera.aspect = window.innerWidth / window.innerHeight;
    camera.updateProjectionMatrix();

    renderer.setSize(window.innerWidth, window.innerHeight);
}

function onDocumentMouseMove(event) {
    mouseX = (event.clientX - windowHalfX) / 2;
    mouseY = (event.clientY - windowHalfY) / 2;
}

//

function animate() {
    requestAnimationFrame(animate);
    render();
}

function render() {
    camera.position.x += (mouseX - camera.position.x) * 0.05;
    camera.position.y += (-mouseY - camera.position.y) * 0.05;

    camera.lookAt(scene.position);

    scene.background = exrBackground;
    renderer.toneMappingExposure = 1.0;
    renderer.render(scene, camera);
}
</script>

如果您不喜欢 SO 片段，这里是您可以投票/分叉/分享的 CodePen 版本。