该类在内部由PointLights所使用，以用于计算阴影。
//Create a WebGLRenderer and turn on shadows in the renderer
const renderer = new v3d.WebGLRenderer();
renderer.shadowMap.enabled = true;
renderer.shadowMap.type = v3d.PCFSoftShadowMap; // default v3d.PCFShadowMap
//Create a PointLight and turn on shadows for the light
const light = new v3d.PointLight(0xffffff, 1, 100);
light.position.set(0, 10, 0);
light.castShadow = true; // default false
app.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)
const sphereGeometry = new v3d.SphereBufferGeometry(5, 32, 32);
const sphereMaterial = new v3d.MeshStandardMaterial({ color: 0xff0000 });
const sphere = new v3d.Mesh(sphereGeometry, sphereMaterial);
sphere.castShadow = true; //default is false
sphere.receiveShadow = false; //default
app.scene.add(sphere);
//Create a plane that receives shadows (but does not cast them)
const planeGeometry = new v3d.PlaneBufferGeometry(20, 20, 32, 32);
const planeMaterial = new v3d.MeshStandardMaterial({ color: 0x00ff00 })
const plane = new v3d.Mesh(planeGeometry, planeMaterial);
plane.receiveShadow = true;
app.scene.add(plane);
//Create a helper for the shadow camera (optional)
const helper = new v3d.CameraHelper(light.shadow.camera);
app.scene.add(helper);
创建一个新的PointLightShadow。该方法不是直接调用的 —— 其在内部由PointLight调用。
共有属性请参见其基类LightShadow。
共有方法请参见其基类LightShadow。
Update the matrices for the camera and shadow, used internally by the renderer.
light -- the light for which the shadow is being rendered.
viewportIndex -- calculates the matrix for this viewport