examples/example30.html


<!DOCTYPE html>
<html>
 <head> 
  <title>Example 30 - Merge objects</title> 
  <style>
    body{
      margin: 0;
      overflow: hidden;
    }

    #stats {  /* Align stats top-left */
      position: absolute;
      left: 0px;
      top: 0px;
    }
  </style> 
  </head>
  <body>
  <!-- JavaScript libraries -->
  <script src="http://cdnjs.cloudflare.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> 
  <script src="http://cdnjs.cloudflare.com/ajax/libs/three.js/r67/three.min.js"></script>
  <script src="http://cdnjs.cloudflare.com/ajax/libs/stats.js/r11/Stats.min.js"></script>
  <script src="http://cdnjs.cloudflare.com/ajax/libs/dat-gui/0.5/dat.gui.min.js"></script>
  <script src="assets/libs/TrackballControls.js"></script>
  <!-- Javascript code that runs our Three.js examples --> 
  <script>
    // once everything is loaded, we run our Three.js stuff.
    $(function () {
      
      var stats = initStats();

      // create a scene, that will hold all our elements such as objects, cameras and lights.
      var scene = new THREE.Scene();

      // create a camera, which defines where we're looking at.
      var camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 1, 500);

      // create a render and set the size
      var renderer = new THREE.WebGLRenderer();

      renderer.setClearColor(new THREE.Color(0x00000, 1.0));
      renderer.setSize(window.innerWidth, window.innerHeight);
      renderer.shadowMapEnabled = true;

      // position and point the camera to the center of the scene
      camera.position.set(0,40,50);
      camera.lookAt(scene.position);

      // add the output of the renderer to the html element
      $('body').append(renderer.domElement);

      // call the render function
      var step = 0;

      var cubeMaterial = new THREE.MeshNormalMaterial({color: 0x00ff00, transparent: true, opacity: 0.5 });
      var controls = new function () {
        this.rotationSpeed = 0.02;
        this.combined = false;
        this.numberOfObjects = 500;

        this.redraw = function () {
          var toRemove = [];
          scene.traverse(function (e) {
            if (e instanceof THREE.Mesh) {
              toRemove.push(e);
            }
          });
          toRemove.forEach(function (e) {
            scene.remove(e)
          });

          // add a large number of cubes
          if (controls.combined) {
            var geometry = new THREE.Geometry();
            for (var i = 0; i < controls.numberOfObjects; i++) {
              geometry.merge(controls.addCube());
            }
            scene.add(new THREE.Mesh(geometry, cubeMaterial));
          } else {
            for (var i = 0; i < controls.numberOfObjects; i++) {
              scene.add(new THREE.Mesh(controls.addCube(), cubeMaterial));
            }
          }
        }

        this.addCube = addcube;

        this.outputObjects = function () {
          console.log(scene.children);
        }
      }

      var gui = new dat.GUI();

      gui.add(controls, 'numberOfObjects', 0, 20000);
      gui.add(controls, 'combined').onChange(controls.redraw);
      gui.add(controls, 'redraw');


      controls.redraw();

      render();

      var rotation = 0;

      function translateGeometry (geometry, vector) {
        geometry.vertices.forEach(function (v) {
          v.add(vector);
        });
        geometry.verticesNeedUpdate.true;
      }

      function addcube() {
        var cubeSize = 1.0;
        var cubeGeometry = new THREE.BoxGeometry(cubeSize, cubeSize, cubeSize);
        var x = -60 + Math.round((Math.random() * 100));
        var y = Math.round((Math.random() * 10));
        var z = -150 + Math.round((Math.random() * 175));
        var v = new THREE.Vector3(x,y,z);
        translateGeometry(cubeGeometry, v);
        return cubeGeometry;
      };

      function render() {

        rotation += 0.005;

        stats.update();

        camera.position.x = Math.sin(rotation) * 50;
        // camera.position.y = Math.sin(rotation) * 40;
        camera.position.z = Math.cos(rotation) * 50;
        camera.lookAt(scene.position);

        // render using requestAnimationFrame
        requestAnimationFrame(render);
        renderer.render(scene, camera);
      }

      function initStats() {
        var stats = new Stats();
        stats.setMode(0); // 0: fps, 1: ms
        $('body').append(stats.domElement);
        return stats;
      }
    });
  </script>  
 </body>
</html>