Three.js飞机不投阴影

Question

我在一个更大的平面上堆叠一个平面和一个球体，如下图所示

从WebGL检查器看，似乎所有三个对象都在阴影贴图中绘制，但只有球体有效地出现在阴影贴图中，导致较小的平面永远不会在较大的平面上投射阴影

这是场景构建

renderer.shadowMap.enabled = true

camera = new THREE.PerspectiveCamera(50, window.innerWidth / window.innerHeight, 1, 5000);
camera.position.z = 600;
window.controls = new THREE.OrbitControls(camera, renderer.domElement);


light = new THREE.SpotLight(0xffffff, 1, 0, Math.PI / 2);
light.position.set(1, 1000, 1);
light.castShadow = true;
light.shadow = new THREE.LightShadow(new THREE.PerspectiveCamera(50, 1, 1, 5000));

scene.add(light);

var planeGeometry = new THREE.PlaneGeometry( innerWidth * 0.5, innerHeight * 0.5, 10, 10);
var plane = new THREE.Mesh( planeGeometry, new THREE.MeshPhongMaterial({ color: 0xffcccc }));
plane.rotation.x = -Math.PI / 2;
plane.castShadow = true;
plane.receiveShadow = true;
scene.add(plane);


var sphere = new THREE.SphereGeometry(100, 16, 8);
var spheremesh = new THREE.Mesh(sphere, new THREE.MeshPhongMaterial( ));
spheremesh.position.y = 200;
spheremesh.castShadow = true;
spheremesh.receiveShadow = true;
scene.add(spheremesh);

var planeGeometry1 = new THREE.PlaneGeometry( innerWidth, innerHeight, 10, 10);
var plane1 = new THREE.Mesh( planeGeometry1, new THREE.MeshPhongMaterial( ));
plane1.position.y = -250;
plane1.rotation.x = -Math.PI / 2;
plane1.castShadow = true;
plane1.receiveShadow = true;
scene.add(plane1);

Answer 1

默认情况下，three.js会在生成阴影贴图时剔除前脸。

renderer.shadowMap.renderReverseSided = true; // default is true

这意味着只有背面（从灯光的角度来看）投射阴影。剔除飞机的前脸不会留下任何东西来投下阴影。

因此，一种选择是将您的PlaneGeometry替换为具有深度的BoxGeometry。

第二个选项是设置

renderer.shadowMap.renderSingleSided = false; // default is true

在这种情况下，您的飞机会投射阴影，但由于您同时拥有plane.castShadow = true和plane.receiveShadow = true，因此可能存在自阴影工件。

通常，第一个选项是最佳选择。

three.js r.86