BabylonJS - 网格实例

如果您想在场景中绘制相同的网格，请使用实例。

语法

var newInstance = mesh.createInstance("i" + index); // 创建新实例

演示

<!doctype html>
<html>
   <head>
      <meta charset = "utf-8">
      <title>BabylonJs - Basic Element-Creating Scene</title>
      <script src = "babylon.js"></script>
      <style>
         canvas {width: 100%; height: 100%;}
      </style>
   </head>
   
   <body>
      <canvas id = "renderCanvas"></canvas>
      <script type = "text/javascript">
         var canvas = document.getElementById("renderCanvas");
         var engine = new BABYLON.Engine(canvas, true);
         
         var createScene  = function() {
            var scene = new BABYLON.Scene(engine);
            scene.clearColor = BABYLON.Color3.Gray();
            
            // 这将创建并定位一个自由相机(非网格)
            var camera = new BABYLON.FreeCamera("camera1", new BABYLON.Vector3(0, 5, -10), scene);
            
            // 这将相机定位到场景原点
            camera.setTarget(BABYLON.Vector3.Zero());
            
            // 这将相机附加到画布
            camera.attachControl(canvas, true);
            
            var light = new BABYLON.DirectionalLight("dir01", new BABYLON.Vector3(0, -1, -0.3), scene);
            light.position = new BABYLON.Vector3(20, 60, 30);
            
            // 地面
            var ground = BABYLON.Mesh.CreateGround("ground1", 50, 50, 2, scene);
            ground.receiveShadows = true;
            
            var array_instances = [];
            // 树木
            BABYLON.SceneLoader.ImportMesh("", "scenes/", "Rabbit.babylon", scene, function (newMeshes,articleSystems,skeletons) {
               var rabbit = newMeshes[1];
               rabbit.isVisible = false;

               var range = 50;
               var count = 100;
               for (var index = 0; index < count; index++) {
                  var newInstance = rabbit.createInstance("i" + index);
                  var x = range / 2 - Math.random() * range;
                  var z = range / 2 - Math.random() * range;

                  newInstance.position = new BABYLON.Vector3(x, 0, z);
                  newInstance.scaling = new BABYLON.Vector3(0.05, 0.05, 0.05);
                  array_instances.push(newInstance);
               }	
            });
            return scene;
         };
         var scene = createScene();
         engine.runRenderLoop(function() {
            scene.render();
         });
      </script>
   </body>
</html>

在上面的演示链接中，我们使用了 Rabbit.babylon 网格。您可以从此处下载 Rabbit.babylon 的 json 文件

Rabbit.babylon

将文件保存在场景中以获取下面显示的输出。

输出

上面的代码行将生成以下输出 −

说明

以下代码有助于在场景中创建相同的网格 −

var array_instances = [];

// Trees
BABYLON.SceneLoader.ImportMesh("", "scenes/", "Rabbit.babylon", scene, function (newMeshes, particleSystems, skeletons) {
   var rabbit = newMeshes[1];
   rabbit.isVisible = false;

   var range = 50;
   var count = 100;
   for (var index = 0; index < count; index++) {
    var newInstance = rabbit.createInstance("i" + index); // 创建新实例
    var x = range / 2 - Math.random() * range;
    var z = range / 2 - Math.random() * range;
    
    newInstance.position = new BABYLON.Vector3(x, 0, z); // 设置所创建实例的位置。
    newInstance.scaling = new BABYLON.Vector3(0.05, 0.05, 0.05);//在 x、y 和 z 轴上缩放实例。
    array_instances.push(newInstance);
   }
});
return scene;