ThreeJS系列1_CinematicCameraJS外掛詳解

隨遇丿而安發表於2020-10-08
JS

ThreeJS系列1_CinematicCameraJS外掛詳解

接著上篇 ThreeJS系列1_CinematicCameraJS外掛介紹

目錄

1. 屬性的來龍去脈

type

// 描述資訊
this.type = 'CinematicCamera';

shaderSettings

  1. 初始化程式碼
	this.shaderSettings = {
		rings: 3,
		samples: 4
	};
  1. 使用地點
this.postprocessing.materialBokeh = new ShaderMaterial( {
    //...忽略程式碼
    defines: {
        RINGS: this.shaderSettings.rings,
        SAMPLES: this.shaderSettings.samples,
        DEPTH_PACKING: 1
    }
} );
  1. 小結

shaderSettings 最終作為 postprocessing.materialBokeh 的值使用

shaderSettings --> postprocessing.materialBokeh

materialDepth

  1. 初始化程式碼
//	ShaderMaterial 使用自定義shader渲染的材質。 shader是一個用GLSL編寫的小程式 ，在GPU上執行。
    this.materialDepth = new ShaderMaterial( {
     uniforms: depthShader.uniforms,
     vertexShader: depthShader.vertexShader,
     fragmentShader: depthShader.fragmentShader
    } );
	this.materialDepth.uniforms[ 'mNear' ].value = near;
	this.materialDepth.uniforms[ 'mFar' ].value = far;
  1. 使用地點
// scene.overrideMaterial: 
// 如果不為空，它將強制場景中的每個物體使用這裡的材質來渲染。預設值為null。
scene.overrideMaterial = this.materialDepth;
  1. 小結

當做 scene.overrideMaterial

postprocessing

  1. 初始化程式碼
this.postprocessing = { enabled: true };
  1. 使用地點
// 主要在這個方法中進行更多的初始化
this.initPostProcessing();
...
// 在這個方法中進行聚焦操作
CinematicCamera.prototype.focusAt = function ( focusDistance ) {
    ...
    this.postprocessing.bokeh_uniforms[ 'focalDepth' ].value = this.ldistance;
};
  1. 總結

CinematicCamera主要引數在postprocessing中設定

2. 方法作用

setLens

// 提供fnumber和coc(混淆圈)作為額外引數
CinematicCamera.prototype.setLens = function ( focalLength, filmGauge, fNumber, coc ) {

 // 對於cinematicCamera來說，擁有一個預設的鏡頭設定很重要
 if ( focalLength === undefined ) focalLength = 35;
 if ( filmGauge !== undefined ) this.filmGauge = filmGauge;

 this.setFocalLength( focalLength );

 // 如果沒有提供fnumber和coc, cinematicCamera嘗試充當一個基本的PerspectiveCamera
 if ( fNumber === undefined ) fNumber = 8;
 if ( coc === undefined ) coc = 0.019;

 this.fNumber = fNumber;
 this.coc = coc;

 // fNumber是光圈對焦的
 this.aperture = focalLength / this.fNumber;

 // 超過焦距的鏡頭時需要計算depthOfField試圖集中在遠處給fNumber和focalLength
 this.hyperFocal = ( focalLength * focalLength ) / ( this.aperture * this.coc );

};

作用: 初始化相機焦距相關

focusAt

// 距相機較遠的對焦功能, focusDistance 表示對焦物體到相機距離
CinematicCamera.prototype.focusAt = function ( focusDistance ) {

 if ( focusDistance === undefined ) focusDistance = 20;

 var focalLength = this.getFocalLength();

 // 與相機之間的距離(正常情況下為函式集)來聚焦
 this.focus = focusDistance;

 // 距相機最近的對焦點(未使用)
 this.nearPoint = ( this.hyperFocal * this.focus ) / ( this.hyperFocal + ( this.focus - focalLength ) );

 // 距相機最遠的對焦點(未使用)
 this.farPoint = ( this.hyperFocal * this.focus ) / ( this.hyperFocal - ( this.focus - focalLength ) );

 // 所有東西都集中在裡面的空間的間隙或寬度(未使用)
 this.depthOfField = this.farPoint - this.nearPoint;

 // 考慮標準鏡頭的最小焦距(未使用)
 if ( this.depthOfField < 0 ) this.depthOfField = 0;

 this.sdistance = this.smoothstep( this.near, this.far, this.focus );

 this.ldistance = this.linearize( 1 - this.sdistance );

 this.postprocessing.bokeh_uniforms[ 'focalDepth' ].value = this.ldistance;
};
// 線性化, 具體原理我也不懂
CinematicCamera.prototype.linearize = function ( depth ) {
	var zfar = this.far;
	var znear = this.near;
	return - zfar * znear / ( depth * ( zfar - znear ) - zfar );
};
// 平滑處理
CinematicCamera.prototype.smoothstep = function ( near, far, depth ) {
	var x = this.saturate( ( depth - near ) / ( far - near ) );
	return x * x * ( 3 - 2 * x );
};
// 判斷x是否在0-1之間, 若x>1, 返回1; 若x<0, 返回0; 若x在0-1, 返回x
CinematicCamera.prototype.saturate = function ( x ) {
	return Math.max( 0, Math.min( 1, x ) );
};

作用: 修改相機的焦距, 雖然原理可能看不懂, 但是使用起來還是十分簡單的: focusAt(焦距)

initPostProcessing

CinematicCamera.prototype.initPostProcessing = function () {

 // 判斷是否啟用postprocessing(後置處理), 不啟用, 初始化直接結束, this指例項化相機物件
 if ( this.postprocessing.enabled ) {

  this.postprocessing.scene = new Scene();

  this.postprocessing.camera = new OrthographicCamera( window.innerWidth / - 2, window.innerWidth / 2, window.innerHeight / 2, window.innerHeight / - 2, - 10000, 10000 );

  this.postprocessing.scene.add( this.postprocessing.camera );

  var pars = { minFilter: LinearFilter, magFilter: LinearFilter, format: RGBFormat };
  // WebGLRenderTarget: render target是一個緩衝，就是在這個緩衝中，視訊卡為正在後臺渲染的場景繪製
  // 畫素。 它用於不同的效果，例如用於在一個影像顯示在螢幕上之前先做一些處理。
  this.postprocessing.rtTextureDepth = new WebGLRenderTarget( window.innerWidth, window.innerHeight, pars );
  this.postprocessing.rtTextureColor = new WebGLRenderTarget( window.innerWidth, window.innerHeight, pars );

  var bokeh_shader = BokehShader;

  this.postprocessing.bokeh_uniforms = UniformsUtils.clone( bokeh_shader.uniforms );
// 可以設定的引數如下所示
  this.postprocessing.bokeh_uniforms[ "tColor" ].value = this.postprocessing.rtTextureColor.texture;
  this.postprocessing.bokeh_uniforms[ "tDepth" ].value = this.postprocessing.rtTextureDepth.texture;

  this.postprocessing.bokeh_uniforms[ "manualdof" ].value = 0;
  this.postprocessing.bokeh_uniforms[ "shaderFocus" ].value = 0;

  this.postprocessing.bokeh_uniforms[ "fstop" ].value = 2.8;

  this.postprocessing.bokeh_uniforms[ "showFocus" ].value = 1;

  this.postprocessing.bokeh_uniforms[ "focalDepth" ].value = 0.1;

  //console.log( this.postprocessing.bokeh_uniforms[ "focalDepth" ].value );

  this.postprocessing.bokeh_uniforms[ "znear" ].value = this.near;
  this.postprocessing.bokeh_uniforms[ "zfar" ].value = this.near;


  this.postprocessing.bokeh_uniforms[ "textureWidth" ].value = window.innerWidth;

  this.postprocessing.bokeh_uniforms[ "textureHeight" ].value = window.innerHeight;

  this.postprocessing.materialBokeh = new ShaderMaterial( {
   uniforms: this.postprocessing.bokeh_uniforms,
   vertexShader: bokeh_shader.vertexShader,
   fragmentShader: bokeh_shader.fragmentShader,
   defines: {
    RINGS: this.shaderSettings.rings,
    SAMPLES: this.shaderSettings.samples,
    DEPTH_PACKING: 1
   }
  } );

  this.postprocessing.quad = new Mesh( new PlaneBufferGeometry( window.innerWidth, window.innerHeight ), this.postprocessing.materialBokeh );
  this.postprocessing.quad.position.z = - 500;
  this.postprocessing.scene.add( this.postprocessing.quad );

 }

};

renderCinematic

加入啟用了postprocessing, 那麼使用這個方法渲染場景, 代替renderer.render(scene, camera)

CinematicCamera.prototype.renderCinematic = function ( scene, renderer ) {

 if ( this.postprocessing.enabled ) {

  var currentRenderTarget = renderer.getRenderTarget();

  renderer.clear();

  // Render scene into texture

  scene.overrideMaterial = null;
  renderer.setRenderTarget( this.postprocessing.rtTextureColor );
  renderer.clear();
  renderer.render( scene, this );

  // Render depth into texture

  scene.overrideMaterial = this.materialDepth;
  renderer.setRenderTarget( this.postprocessing.rtTextureDepth );
  renderer.clear();
  renderer.render( scene, this );

  // Render bokeh composite

  renderer.setRenderTarget( null );
  renderer.render( this.postprocessing.scene, this.postprocessing.camera );

  renderer.setRenderTarget( currentRenderTarget );

 }

};

3. 使用步驟

  • 可以更改的屬性
  • 使用步驟
  1. 建立相機, 和PerspectiveCamera一樣
camera = new CinematicCamera(60, window.innerWidth / window.innerHeight, 1, 1000);
  1. 初始化焦距
// 初始化焦距
camera.setLens(5);
// 初始化位置
camera.position.set(2, 1, 500);
  1. 設定相機相關屬性

    1. 建立屬性物件, 下面所有都可以設定

      let effectController = {
  // BokehDepthShader中屬性
  focalLength: 15,
  // jsDepthCalculation: true,
  // shaderFocus: false,
  fstop: 2.8,
  // maxblur: 1.0,
  showFocus: false,
  focalDepth: 3,
  // manualdof: false,
  // vignetting: false,
  // depthblur: false,
  //
  // threshold: 0.5,
  // gain: 2.0,
  // bias: 0.5,
  // fringe: 0.7,
  //
  // focalLength: 22,
  // noise: true,
  // pentagon: false,
  //
  // dithering: 0.0001
};

    2. 將屬性物件賦值到相機上

      let matChanger = function(){
  // 遍歷屬性物件, 賦值到相機的屬性上
  for(let e in effectController){
    if( e in camera.postprocessing.bokeh_uniforms){
      camera.postprocessing.bokeh_uniforms[e].value = effectController[e];

    }
  }
  camera.postprocessing.bokeh_uniforms[ 'znear' ].value = camera.near;
  camera.postprocessing.bokeh_uniforms[ 'zfar' ].value = camera.far;
  camera.setLens( effectController.focalLength, camera.frameHeight, effectController.fstop, camera.coc );
  effectController[ 'focalDepth' ] = camera.postprocessing.bokeh_uniforms[ 'focalDepth' ].value;
};
// 執行方法
matChanger();
  2. 設定焦距
camera.focusAt(targetDistance);

4. 原始碼

<template>
  <div ref="container">

  </div>
</template>

<script>

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

  let scene, renderer;
  let camera;

  let container, stats;

  let raycaster, mouse = new THREE.Vector2(), INTERSECTED;
  let radius = 100,
      theta = 0;

  function init() {
    container = this.$refs.container;

    scene = new THREE.Scene();
    scene.background = new THREE.Color( 0xf0f0f0 );

    renderer = new THREE.WebGLRenderer({
      antialias: true,
    });
    renderer.setPixelRatio(window.devicePixelRatio);
    renderer.setSize(window.innerWidth, window.innerHeight);
    container.appendChild(renderer.domElement);

    // camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight);
    // camera.position.set(4, 5, 6);
    camera = new CinematicCamera(60, window.innerWidth / window.innerHeight, 1, 1000);
    // 重寫了一個PerspectiveCamera不要的方法
    camera.setLens(5);
    camera.position.set(2, 1, 500);

    // let orbitControls = new OrbitControls(camera, renderer.domElement);
    // scene.add(new THREE.AxesHelper(5));
    stats = new Stats();
    container.appendChild(stats.dom);

    // light
    scene.add( new THREE.AmbientLight( 0xffffff, 0.3 ) );
    var light = new THREE.DirectionalLight( 0xffffff, 0.35 );
    light.position.set( 1, 1, 1 ).normalize();
    scene.add( light );

    var geometry = new THREE.SphereBufferGeometry(10, 32, 32);
    // var geometry = new THREE.BoxBufferGeometry( 20, 20, 20 );

    for ( var i = 0; i < 1500; i ++ ) {

      // 不一樣的顏色
      var object = new THREE.Mesh( geometry, new THREE.MeshLambertMaterial( { color: Math.random() * 0xffffff } ) );

      // 位置 -400到400
      object.position.x = Math.random() * 800 - 400;
      object.position.y = Math.random() * 800 - 400;
      object.position.z = Math.random() * 800 - 400;

      scene.add( object );
    }

    raycaster = new THREE.Raycaster();

    let effectController = {
      // BokehDepthShader中屬性
      focalLength: 15,
      // jsDepthCalculation: true,
      // shaderFocus: false,
      fstop: 2.8,
      // maxblur: 1.0,
      showFocus: false,
      focalDepth: 3,
      // manualdof: false,
      // vignetting: false,
      // depthblur: false,
      //
      // threshold: 0.5,
      // gain: 2.0,
      // bias: 0.5,
      // fringe: 0.7,
      //
      // focalLength: 22,
      // noise: true,
      // pentagon: false,
      //
      // dithering: 0.0001
    };

    let matChanger = function(){
      for(let e in effectController){
        if( e in camera.postprocessing.bokeh_uniforms){
          camera.postprocessing.bokeh_uniforms[e].value = effectController[e];

        }
      }
      camera.postprocessing.bokeh_uniforms[ 'znear' ].value = camera.near;
      camera.postprocessing.bokeh_uniforms[ 'zfar' ].value = camera.far;
      camera.setLens( effectController.focalLength, camera.frameHeight, effectController.fstop, camera.coc );
      effectController[ 'focalDepth' ] = camera.postprocessing.bokeh_uniforms[ 'focalDepth' ].value;
    };

    matChanger();

    this.camera = camera;

    window.addEventListener('resize', onResize, false);
    window.addEventListener('mousemove', onMousemove, false);
  }

  function onMousemove(event) {
    // 取消事件的預設動作
    event.preventDefault();

    mouse.x = (event.clientX / window.innerWidth) * 2 - 1;
    mouse.y = -(event.clientY / window.innerHeight) * 2 + 1;

  }

  function onResize() {
    camera.aspect = window.innerWidth / window.innerHeight;
    camera.updateProjectionMatrix();

    renderer.setSize(window.innerWidth, window.innerHeight);
  }

  function animation() {
    stats.update();

    render();
    // renderer.render(scene, camera);

    requestAnimationFrame(animation);
  }

  function render() {
    theta += 0.1;
    // MathUtils.degToRad(theta) 將度轉化為弧度
    camera.position.x = radius * Math.sin(THREE.MathUtils.degToRad(theta));
    camera.position.y = radius * Math.sin(THREE.MathUtils.degToRad(theta));
    camera.position.z = radius * Math.cos(THREE.MathUtils.degToRad(theta));

    camera.lookAt(scene.position);

    // 更新物體及後代的全域性變換
    camera.updateMatrixWorld();

    raycaster.setFromCamera(mouse, camera);

    let intersects = raycaster.intersectObjects(scene.children);

    if (intersects.length > 0) {
      let targetDistance = intersects[0].distance;

      camera.focusAt(targetDistance);

      if (INTERSECTED != intersects[0].object) {
        if(INTERSECTED) INTERSECTED.material.emissive.setHex( INTERSECTED.currentHex );

        INTERSECTED = intersects[ 0 ].object;
        INTERSECTED.currentHex = INTERSECTED.material.emissive.getHex();
        // MeshLambertMaterial的屬性emissive
        // 材質的放射（光）顏色，基本上是不受其他光照影響的固有顏色。預設為黑色。
        INTERSECTED.material.emissive.setHex( 0xff0000 );
      }
    }else {
      if(INTERSECTED) INTERSECTED.material.emissive.setHex( INTERSECTED.currentHex );

      INTERSECTED = null;

    }

    if (camera.postprocessing.enabled) {
      camera.renderCinematic(scene, renderer);
    }else {
      scene.overrideMaterial = null;

      renderer.clear();
      renderer.render(scene, camera);
    }

  }


  export default {
    name: "CameraCinematic",
    data(){
      return {
        effectController: {

        },
        camera: {},
      }
    },
    mounted() {
      init.call(this);
      animation();
    }
  }
</script>

<style scoped>

</style>

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