Putting three.js animation inside of div

问题

This is three.js animation code example:

<script defer="defer">
  var angularSpeed = 0.2; 
  var lastTime = 0;
  function animate(){
    var time = (new Date()).getTime();
    var timeDiff = time - lastTime;
    var angleChange = angularSpeed * timeDiff * 2 * Math.PI / 1000;
    plane.rotation.z += angleChange;
    lastTime = time;
    renderer.render(scene, camera);
    requestAnimationFrame(function(){
        animate();
    });
  }
  var renderer = new THREE.WebGLRenderer();
  renderer.setSize(window.innerWidth, window.innerHeight);
  document.body.appendChild(renderer.domElement);
  var camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 1, 1000);
  camera.position.y = -450;
  camera.position.z = 400;
  camera.rotation.x = 45 * (Math.PI / 180);
  var scene = new THREE.Scene();
  var plane = new THREE.Mesh(new THREE.PlaneGeometry(300, 300), new THREE.MeshNormalMaterial());
  plane.overdraw = true;
  scene.add(plane);
  animate();
 </script>

I would like to bind this animation code to some specific div via div id. So, animation would be displayed inside of div. That would allow me to easily manipulate animation location with css. I was having in mind something like this:

html:

<canvas id="myCanvas" width="578" height="200"></canvas>

javascript:

var canvas = document.getElementById('myCanvas');
var context = canvas.getContext('2d');
// do stuff here

But I haven't found a way to do something like this with three.js. As you can see in code example, there is no canvas element that I can refer to. Any ideas?

回答1:

You can use a pattern like the following:

<div id="canvas">

#canvas {
    background-color: #000;
    width: 200px;
    height: 200px;
    border: 1px solid black;
    margin: 100px;
    padding: 0px;
    position: static; /* fixed or static */
    top: 100px;
    left: 100px;
}

container = document.getElementById( 'canvas' );
document.body.appendChild( container );

renderer = new THREE.WebGLRenderer();
renderer.setSize( 200, 200 );
container.appendChild( renderer.domElement );

Fiddle: http://jsfiddle.net/fek9ddg5/1/

Also see THREE.js Ray Intersect fails by adding div

three.js r.69

回答2:

If you don't want to hardcode renderer size then below piece of code can help you.

I am dynamically calculating canvas height and width and then accordingly setting the renderer's size and camera's position.

CSS

            #canvas {
             background-color: #FFF;
             width: 200px;
             height:200px;
             border: 1px solid black;
              }

HTML

<div id="canvas"/>

JavaScript

         //Add Renderer
         renderer = new THREE.CanvasRenderer();
         var container = document.getElementById('canvas');
         var w = container.offsetWidth;
         var h = container.offsetHeight;
         renderer.setSize(w, h);
         container.appendChild(renderer.domElement);

        //Add Camera
        camera = new THREE.PerspectiveCamera( 75, w / h, 2, 1000 );
        camera.position.z = 400;

        //Create Scene with geometry, material-> mesh
        scene = new THREE.Scene();
        geometry = new THREE.IcosahedronGeometry( 200, 3 );
        material = new THREE.MeshBasicMaterial( { color: 0x000000, wireframe: true, wireframeLinewidth: 1 } );
        mesh = new THREE.Mesh( geometry, material );
        scene.add( mesh );

来源：https://stackoverflow.com/questions/17507525/putting-three-js-animation-inside-of-div

标签

html5-canvas

three.js