如何用3j制作加载屏幕?

I have a large amount of textures and models to load into my project. I am trying to show a progress bars while everything is loading. I think the LoadingManager does just what I need as it tracks the progress of all loaded assets.

我有大量的纹理和模型来加载到我的项目中。在加载所有内容时，我试图显示进度条。我认为LoadingManager所做的正是我所需要的，因为它跟踪所有已加载资产的进度。

I'm using the JSONLoader and TextureLoader.

我正在使用JSONLoader和TextureLoader。

If anyone could show me how to do implement this in the example code would be awesome.

如果有人能告诉我如何在示例代码中实现这一点，那将是非常棒的。

var camera, scene, renderer;

 init();
 animate();

 function init() {

   camera = new THREE.PerspectiveCamera(70, window.innerWidth / window.innerHeight, 1, 1000);
   camera.position.z = 400;

   scene = new THREE.Scene();


   // Load Textures 
   var modeltexture1 = new THREE.TextureLoader().load('modeltexture1.jpg');
   var modeltexture2 = new THREE.TextureLoader().load('modeltexture2.jpg');
   var modeltexture3 = new THREE.TextureLoader().load('modeltexture3.jpg');
   var modeltexture4 = new THREE.TextureLoader().load('modeltexture4.jpg');
  
   // Materials
   var material = {
     "texture1": new THREE.MeshPhongMaterial({ map: modeltexture1 }),
     "texture2": new THREE.MeshPhongMaterial({ map: modeltexture2 }),
     "texture3": new THREE.MeshPhongMaterial({ map: modeltexture3 }),
     "texture4": new THREE.MeshPhongMaterial({ map: modeltexture4 }),
   }

   // Lights
   scene.add(new THREE.AmbientLight(0xcccccc));
   pointLight = new THREE.PointLight(0xff4400, 5, 30);
   pointLight.position.set(5, 0, 0);
   scene.add(pointLight);
  
   var loader = new THREE.JSONLoader();


   // Model1
   var model1 = new THREE.Object3D;
   scene.add(model1);

   loader.load("model1.js", function(geometry) {
     var mainmodel1 = new THREE.Mesh(geometry, material["texture1"]);
     model1.add(mainmodel1);
   }); 
   
   // Model2
   var model2 = new THREE.Object3D;
   scene.add(model2);

   loader.load("model2.js", function(geometry) {
     var mainmodel2 = new THREE.Mesh(geometry, material["texture2"]);
     model2.add(mainmodel2);
   });
   
   // Model3
   var model3 = new THREE.Object3D;
   scene.add(model3);

   loader.load("model3.js", function(geometry) {
     var mainmodel3 = new THREE.Mesh(geometry, material["texture3"]);
     model3.add(mainmodel3);
   });   
   
   // Model4
   var model4 = new THREE.Object3D;
   scene.add(model4);

   loader.load("model4.js", function(geometry) {
     var mainmodel4 = new THREE.Mesh(geometry, material["texture4"]);
     model4.add(mainmodel4);
   });  
   
   renderer = new THREE.WebGLRenderer();
   renderer.setPixelRatio(window.devicePixelRatio);
   renderer.setSize(window.innerWidth, window.innerHeight);
   document.body.appendChild(renderer.domElement);

   //

   window.addEventListener('resize', onWindowResize, false);

 }

 function onWindowResize() {

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

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

 }

 function animate() {

   requestAnimationFrame(animate);
   renderer.render(scene, camera);

 }

body {
  margin: 0;
}
canvas {
  width: 100%;
  height: 100%
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/r74/three.min.js"></script>

2 个解决方案

#1

LoadingManager Update

as @2pha points out, the below is pointless as THREE already implements a loading Manager - the below will remain for posterity, but have a look at this:

正如@2pha所指出的，以下内容毫无意义，因为三家公司已经实现了一个加载管理器——以下内容将保留给子孙后代，但请看以下内容:

https://threejs.org/docs/?q=loading#api/loaders/managers/LoadingManager

/加载器/经理/ LoadingManager https://threejs.org/docs/?q=loading api

Easy-peasy:

非常简单:

var progress = document.createElement('div');
var progressBar = document.createElement('div');

progress.appendChild(progressBar);

document.body.appendChild(progress);

var manager = new THREE.LoadingManager();
manager.onProgress = function ( item, loaded, total ) {
  progressBar.style.width = (loaded / total * 100) + '%';
};

function addRandomPlaceHoldItImage(){
  var r = Math.round(Math.random() * 4000);
  new THREE.ImageLoader(manager).load('http://placehold.it/' + r + 'x' + r);
}

for(var i = 0; i < 10; i++) addRandomPlaceHoldItImage();

div {
  width: 200px;
  height: 20px;
  background: #000;
  border: 2px solid #000;
}
div > div {
  width: 200px;
  height: 20px;
  background: red;
  border: none;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/r74/three.min.js"></script>

Original Post

Something like the below should do your trick - mind that I have just quickly tested it and there is probably a couple of improvements to make (including using the progress callback in THREE js). I haven't fully refined it either, but it gives you a general implementation of how to do this. I also haven't implemented an error handler, etc... Those are things that take a bit longer to make, but you get the general idea.

下面的一些东西应该可以让您的技巧——我刚刚快速测试过它，并且可能会有一些改进(包括使用三个js中的进度回调)。我也没有对它进行充分的细化，但是它给出了如何实现这个的一般实现。我还没有实现错误处理程序等等……这些东西需要花更长的时间来制作，但是你会得到大致的概念。

You add new types of loaders (that conform to the type + Loader in THREE) and their sources, then initiating the load by simply calling load.

您可以添加新的加载程序类型(在三个中符合type + Loader)及其源，然后通过简单地调用load来启动加载。

Hope it helps.

希望它可以帮助。

(I also made a random function to get some random images from placehold.it since using the same results over and over means that caching kills the server.)

(我还做了一个随机函数，从placehold获得一些随机图像。由于使用了相同的结果，所以缓存会杀死服务器。

function LoaderProgress(callback){
  this.length 	  = -1;
  this.complete   = 0;
  this.domElement = document.createElement('div');
  this.progress	  = document.createElement('div');
  
  this.domElement.appendChild(this.progress);
  this.domElement.className = 'loader-progress-wrapper';
  this.progress.className   = 'loader-progress-progress';
  this.progress.style.width = '0%';
  
  this.callback = callback || function(){};
}
LoaderProgress.prototype.add = function(type, src){
  var result = this[++this.length] = {
    loader: new THREE[type + 'Loader'],
    complete: false,
    source: src
  };
  return result;
}
LoaderProgress.prototype.load = function(){
  this.complete = 0;
  for(var i = 0; i < this.length; i++){
    var current = this[i];
    if(!current.complete){
      current.loader.load(this[i].source, function(result){
        current.complete = result;
        this.complete++;
        this.update();
      }.bind(this));
    }
  }
  return this;
}
LoaderProgress.prototype.update = function(a){
  var progress = this.complete / this.length;
  this.progress.style.width = (progress * 100) + '%';
  if(progress === 1) this.callback(this);
  console.log(progress);
  return progress;
}

var loader = new LoaderProgress(function(){
  // Execute code that needfs the loaded elements here
  alert('All are loaded');
});

document.body.appendChild(loader.domElement);

function addRandomPlaceHoldItImage(){
  var r = Math.round(Math.random() * 4000);
  loader.add('Image', 'http://placehold.it/' + r + 'x' + r);
}

for(var i = 0; i < 10; i++)
  addRandomPlaceHoldItImage();

loader.load();

.loader-progress-wrapper {
  width: 200px;
  height: 20px;
  background: #000;
  border: 2px solid #000;
}
.loader-progress-progress {
  width: 200px;
  height: 20px;
  background: red;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/r74/three.min.js"></script>

#2

Docs: http://threejs.org/docs/#Reference/Loaders/TextureLoader

文档:http://threejs.org/docs/参考/加载器/ TextureLoader

Example: http://threejs.org/examples/#webgl_loader_obj

例如:http://threejs.org/examples/ webgl_loader_obj

Code:

代码:

  var sphereMaterial = new THREE.MeshBasicMaterial();

  var onProgress = function ( xhr ) {
    if ( xhr.lengthComputable ) {
      var percentComplete = xhr.loaded / xhr.total * 100;
      console.log( Math.round(percentComplete, 2) + '% downloaded' );
    }
  };

  var loader = new THREE.TextureLoader();
  var texture = loader.load("___4MB_IMAGE.JPG___", undefined, onProgress);
  sphereMaterial.map = texture;

It solves a similar problem I had - 4MB texture that takes some time to load over the wire...

它解决了我遇到的一个类似的问题——4MB的纹理，需要一段时间才能加载到电线上……