[page:LightShadow] →

# [name]

这是用于在[page:DirectionalLight DirectionalLights]内部计算阴影
与其他阴影类不同，它是使用OrthographicCamera来计算阴影，而不是PerspectiveCamera。这是因为来自DirectionalLight的光线是平行的。

## 例子

`//Create a WebGLRenderer and turn on shadows in the renderer var renderer = new THREE.WebGLRenderer(); renderer.shadowMap.enabled = true; renderer.shadowMap.type = THREE.PCFSoftShadowMap; // default THREE.PCFShadowMap //Create a DirectionalLight and turn on shadows for the light var light = new THREE.DirectionalLight( 0xffffff, 1, 100 ); light.position.set( 0, 1, 0 ); //default; light shining from top light.castShadow = true; // default false scene.add( light ); //Set up shadow properties for the light light.shadow.mapSize.width = 512; // default light.shadow.mapSize.height = 512; // default light.shadow.camera.near = 0.5; // default light.shadow.camera.far = 500; // default //Create a sphere that cast shadows (but does not receive them) var sphereGeometry = new THREE.SphereBufferGeometry( 5, 32, 32 ); var sphereMaterial = new THREE.MeshStandardMaterial( { color: 0xff0000 } ); var sphere = new THREE.Mesh( sphereGeometry, sphereMaterial ); sphere.castShadow = true; //default is false sphere.receiveShadow = false; //default scene.add( sphere ); //Create a plane that receives shadows (but does not cast them) var planeGeometry = new THREE.PlaneBufferGeometry( 20, 20, 32, 32 ); var planeMaterial = new THREE.MeshStandardMaterial( { color: 0x00ff00 } ) var plane = new THREE.Mesh( planeGeometry, planeMaterial ); plane.receiveShadow = true; scene.add( plane ); //Create a helper for the shadow camera (optional) var helper = new THREE.CameraHelper( light.shadow.camera ); scene.add( helper );`

## 构造函数

### [name]( )

创建一个新的[name]，不能直接调用-它是在[page:DirectionalLight DirectionalLights]内部调用使用

## 属性

参阅[page:LightShadow LightShadow]类来了解常用的基本属性

### [property:Camera camera]

在光的世界里。这用于生成场景的深度图;从光的角度来看，其他物体背后的物体将处于阴影中。

## 方法

有关常用方法，请参阅基础[page：LightShadow LightShadow]类。

## 源码

[link:https://github.com/mrdoob/three.js/blob/master/src/lights/[name].js src/lights/[name].js]