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Spot Light Shadow

Video Lecture

Spot Light Shadow

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Description

The Spot Light Shadow uses a PerspectiveCamera frustum to calculate the shadows.

The PerspectiveCamera defaults are

Direction Value
near 0.5
far If the owning spotlight distance is set higher than 0, it will use that, otherwise it uses the default 500
fov the angle property of the owning spotlight via the update method
aspect aspect of the mapSize, default 512/512 = 1

Possible renderer.shadowMap.type values

Type Value
BasicShadowMap gives unfiltered shadow maps - fastest, but lowest quality.
PCFShadowMap (Default) filters shadow maps using the Percentage-Closer Filtering (PCF) algorithm (default).
PCFSoftShadowMap filters shadow maps using the Percentage-Closer Soft Shadows (PCSS) algorithm.
VSMShadowMap filters shadow maps using the Variance Shadow Map (VSM) algorithm. When using VSMShadowMap all shadow receivers will also cast shadows.
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Start Script

./src/client/client.ts

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import * as THREE from 'three'
import { OrbitControls } from 'three/examples/jsm/controls/OrbitControls'
import Stats from 'three/examples/jsm/libs/stats.module'
import { GUI } from 'dat.gui'

const scene = new THREE.Scene()
scene.add(new THREE.AxesHelper(5))

const light = new THREE.SpotLight(0xffffff, 10)
// light.castShadow = true;
// light.shadow.mapSize.width = 512;
// light.shadow.mapSize.height = 512;
// light.shadow.camera.near = 0.5;
// light.shadow.camera.far = 100
scene.add(light)

const helper = new THREE.SpotLightHelper(light)
//const helper = new THREE.CameraHelper(light.shadow.camera);
scene.add(helper)

const camera = new THREE.PerspectiveCamera(75, window.innerWidth / window.innerHeight, 0.1, 1000)
camera.position.z = 7

const renderer = new THREE.WebGLRenderer()
renderer.setSize(window.innerWidth, window.innerHeight)
//renderer.shadowMap.enabled = true
//renderer.shadowMap.type = THREE.PCFSoftShadowMap
//renderer.shadowMap.type = THREE.BasicShadowMap
//renderer.shadowMap.type = THREE.PCFShadowMap
//renderer.shadowMap.type = THREE.VSMShadowMap
document.body.appendChild(renderer.domElement)

new OrbitControls(camera, renderer.domElement)

const planeGeometry = new THREE.PlaneGeometry(100, 20)
const plane = new THREE.Mesh(planeGeometry, new THREE.MeshPhongMaterial())
plane.rotateX(-Math.PI / 2)
plane.position.y = -1.75
//plane.receiveShadow = true;
scene.add(plane)

const torusGeometry = [new THREE.TorusGeometry(), new THREE.TorusGeometry(), new THREE.TorusGeometry(), new THREE.TorusGeometry(), new THREE.TorusGeometry()]

const material = [new THREE.MeshBasicMaterial(), new THREE.MeshLambertMaterial(), new THREE.MeshPhongMaterial(), new THREE.MeshPhysicalMaterial({}), new THREE.MeshToonMaterial()]

const torus = [
  new THREE.Mesh(torusGeometry[0], material[0]),
  new THREE.Mesh(torusGeometry[1], material[1]),
  new THREE.Mesh(torusGeometry[2], material[2]),
  new THREE.Mesh(torusGeometry[3], material[3]),
  new THREE.Mesh(torusGeometry[4], material[4]),
]

const texture = new THREE.TextureLoader().load('img/grid.png')
material[0].map = texture
material[1].map = texture
material[2].map = texture
material[3].map = texture
material[4].map = texture

torus[0].position.x = -8
torus[1].position.x = -4
torus[2].position.x = 0
torus[3].position.x = 4
torus[4].position.x = 8

// torus[0].castShadow = true
// torus[1].castShadow = true
// torus[2].castShadow = true
// torus[3].castShadow = true
// torus[4].castShadow = true

// torus[0].receiveShadow = true
// torus[1].receiveShadow = true
// torus[2].receiveShadow = true
// torus[3].receiveShadow = true
// torus[4].receiveShadow = true

scene.add(torus[0])
scene.add(torus[1])
scene.add(torus[2])
scene.add(torus[3])
scene.add(torus[4])

window.addEventListener('resize', onWindowResize, false)
function onWindowResize() {
  camera.aspect = window.innerWidth / window.innerHeight
  camera.updateProjectionMatrix()
  renderer.setSize(window.innerWidth, window.innerHeight)
  render()
}

const stats = new Stats()
document.body.appendChild(stats.dom)

const data = {
  color: light.color.getHex(),
  mapsEnabled: true,
  //shadowMapSizeWidth: 512,
  //shadowMapSizeHeight: 512,
}

const gui = new GUI()
const lightFolder = gui.addFolder('THREE.Light')
lightFolder.addColor(data, 'color').onChange(() => {
  light.color.setHex(Number(data.color.toString().replace('#', '0x')))
})
lightFolder.add(light, 'intensity', 0, 20, 0.01)

const spotLightFolder = gui.addFolder('THREE.SpotLight')
spotLightFolder.add(light, 'distance', 0, 100, 0.01)
spotLightFolder.add(light, 'decay', 0, 4, 0.1)
spotLightFolder.add(light, 'angle', 0, 1, 0.1)
spotLightFolder.add(light, 'penumbra', 0, 1, 0.1)
//spotLightFolder.add(light.shadow.camera, "near", 0.1, 100).onChange(() => light.shadow.camera.updateProjectionMatrix())
//spotLightFolder.add(light.shadow.camera, "far", 0.1, 100).onChange(() => light.shadow.camera.updateProjectionMatrix())
//spotLightFolder.add(data, "shadowMapSizeWidth", [256, 512, 1024, 2048, 4096]).onChange(() => updateShadowMapSize())
//spotLightFolder.add(data, "shadowMapSizeHeight", [256, 512, 1024, 2048, 4096]).onChange(() => updateShadowMapSize())
spotLightFolder.add(light.position, 'x', -50, 50, 0.01)
spotLightFolder.add(light.position, 'y', -50, 50, 0.01)
spotLightFolder.add(light.position, 'z', -50, 50, 0.01)
spotLightFolder.open()

// function updateShadowMapSize() {
//     light.shadow.mapSize.width = data.shadowMapSizeWidth
//     light.shadow.mapSize.height = data.shadowMapSizeHeight
//     ;(light.shadow.map as any) = null
// }

const meshesFolder = gui.addFolder('Meshes')
meshesFolder.add(data, 'mapsEnabled').onChange(() => {
  material.forEach((m) => {
    if (data.mapsEnabled) {
      m.map = texture
    } else {
      m.map = null
    }
    m.needsUpdate = true
  })
})

function animate() {
  requestAnimationFrame(animate)

  helper.update()

  torus.forEach((t) => {
    t.rotation.y += 0.01
  })

  render()

  stats.update()
}

function render() {
  renderer.render(scene, camera)
}

animate()

Final Script

./src/client/client.ts

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import * as THREE from 'three'
import { OrbitControls } from 'three/examples/jsm/controls/OrbitControls'
import Stats from 'three/examples/jsm/libs/stats.module'
import { GUI } from 'dat.gui'

const scene = new THREE.Scene()
scene.add(new THREE.AxesHelper(5))

const light = new THREE.SpotLight()
light.castShadow = true
light.shadow.mapSize.width = 512
light.shadow.mapSize.height = 512
light.shadow.camera.near = 0.5
light.shadow.camera.far = 100
scene.add(light)

//const helper = new THREE.SpotLightHelper(light)
const helper = new THREE.CameraHelper(light.shadow.camera)
scene.add(helper)

const camera = new THREE.PerspectiveCamera(75, window.innerWidth / window.innerHeight, 0.1, 1000)
camera.position.z = 7

const renderer = new THREE.WebGLRenderer()
renderer.setSize(window.innerWidth, window.innerHeight)
renderer.shadowMap.enabled = true
renderer.shadowMap.type = THREE.PCFSoftShadowMap
//renderer.shadowMap.type = THREE.BasicShadowMap
//renderer.shadowMap.type = THREE.PCFShadowMap
//renderer.shadowMap.type = THREE.VSMShadowMap
document.body.appendChild(renderer.domElement)

new OrbitControls(camera, renderer.domElement)

const planeGeometry = new THREE.PlaneGeometry(100, 20)
const plane = new THREE.Mesh(planeGeometry, new THREE.MeshPhongMaterial())
plane.rotateX(-Math.PI / 2)
plane.position.y = -1.75
plane.receiveShadow = true
scene.add(plane)

const torusGeometry = [new THREE.TorusGeometry(), new THREE.TorusGeometry(), new THREE.TorusGeometry(), new THREE.TorusGeometry(), new THREE.TorusGeometry()]

const material = [new THREE.MeshBasicMaterial(), new THREE.MeshLambertMaterial(), new THREE.MeshPhongMaterial(), new THREE.MeshPhysicalMaterial({}), new THREE.MeshToonMaterial()]

const torus = [
  new THREE.Mesh(torusGeometry[0], material[0]),
  new THREE.Mesh(torusGeometry[1], material[1]),
  new THREE.Mesh(torusGeometry[2], material[2]),
  new THREE.Mesh(torusGeometry[3], material[3]),
  new THREE.Mesh(torusGeometry[4], material[4]),
]

const texture = new THREE.TextureLoader().load('img/grid.png')
material[0].map = texture
material[1].map = texture
material[2].map = texture
material[3].map = texture
material[4].map = texture

torus[0].position.x = -8
torus[1].position.x = -4
torus[2].position.x = 0
torus[3].position.x = 4
torus[4].position.x = 8

torus[0].castShadow = true
torus[1].castShadow = true
torus[2].castShadow = true
torus[3].castShadow = true
torus[4].castShadow = true

torus[0].receiveShadow = true
torus[1].receiveShadow = true
torus[2].receiveShadow = true
torus[3].receiveShadow = true
torus[4].receiveShadow = true

scene.add(torus[0])
scene.add(torus[1])
scene.add(torus[2])
scene.add(torus[3])
scene.add(torus[4])

window.addEventListener('resize', onWindowResize, false)
function onWindowResize() {
  camera.aspect = window.innerWidth / window.innerHeight
  camera.updateProjectionMatrix()
  renderer.setSize(window.innerWidth, window.innerHeight)
  render()
}

const stats = new Stats()
document.body.appendChild(stats.dom)

const data = {
  color: light.color.getHex(),
  mapsEnabled: true,
  shadowMapSizeWidth: 512,
  shadowMapSizeHeight: 512,
}

const gui = new GUI()
const lightFolder = gui.addFolder('THREE.Light')
lightFolder.addColor(data, 'color').onChange(() => {
  light.color.setHex(Number(data.color.toString().replace('#', '0x')))
})
lightFolder.add(light, 'intensity', 0, 2, 0.01)

const spotLightFolder = gui.addFolder('THREE.SpotLight')
spotLightFolder.add(light, 'distance', 0, 100, 0.01)
spotLightFolder.add(light, 'decay', 0, 4, 0.1)
spotLightFolder.add(light, 'angle', 0, 1, 0.1)
spotLightFolder.add(light, 'penumbra', 0, 1, 0.1)
spotLightFolder.add(light.shadow.camera, 'near', 0.1, 100).onChange(() => light.shadow.camera.updateProjectionMatrix())
spotLightFolder.add(light.shadow.camera, 'far', 0.1, 100).onChange(() => light.shadow.camera.updateProjectionMatrix())
spotLightFolder.add(data, 'shadowMapSizeWidth', [256, 512, 1024, 2048, 4096]).onChange(() => updateShadowMapSize())
spotLightFolder.add(data, 'shadowMapSizeHeight', [256, 512, 1024, 2048, 4096]).onChange(() => updateShadowMapSize())
spotLightFolder.add(light.position, 'x', -50, 50, 0.01)
spotLightFolder.add(light.position, 'y', -50, 50, 0.01)
spotLightFolder.add(light.position, 'z', -50, 50, 0.01)
spotLightFolder.open()

function updateShadowMapSize() {
  light.shadow.mapSize.width = data.shadowMapSizeWidth
  light.shadow.mapSize.height = data.shadowMapSizeHeight
  ;(light.shadow.map as any) = null
}

const meshesFolder = gui.addFolder('Meshes')
meshesFolder.add(data, 'mapsEnabled').onChange(() => {
  material.forEach((m) => {
    if (data.mapsEnabled) {
      m.map = texture
    } else {
      m.map = null
    }
    m.needsUpdate = true
  })
})

function animate() {
  requestAnimationFrame(animate)

  helper.update()

  torus.forEach((t) => {
    t.rotation.y += 0.01
  })

  render()

  stats.update()
}

function render() {
  renderer.render(scene, camera)
}

animate()