Three.js 3.js平面不'；投下阴影

我将一个平面和一个球体叠加在一个更大的平面上，如下图所示

从WebGL inspector可以看出，三个对象似乎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，从而导致较小的平面永远不会在较大的平面上投射阴影

这是现场施工

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);

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默认情况下，three.js在生成阴影贴图时会剔除正面

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

这意味着只有背面（从灯光的角度）投射阴影。剔除飞机的正面将不会留下任何阴影

因此，一个选项是用一个薄的具有深度的

BoxGeometry

替换您的

PlaneGeometry

第二个选项是设置

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

在这种情况下，您的平面将投射阴影，但可能存在自阴影瑕疵，因为您同时拥有

plane.castShadow=true

和

plane.receiveShadow=true

通常，第一个选项是最佳选项

3.js r.86