在 forge 查看器中，我可以添加一个新的 THREE.Object3D，但我无法在查看器中选择它。

Question

在 Forge Viewer 中，我编写了一个自定义处理程序。它有一个绑定的双击事件，当它与事件一起触发时，计算被点击的项目

const hitTest = this.viewer.clientToWorld(event.canvasX, event.canvasY, true);

对于普通的对象/网格/材质，可以正常工作，并返回 hitTest.dbId，加上一个 hitTest.point 对象指示我在 3D 空间中单击的位置。我使用该位置创建材质、网格和对象，然后添加到场景中。 （跳过了几个小步骤）

var material_orange = new THREE.MeshLambertMaterial({color: 0xFEBD17});
this.viewer.impl.matman().addMaterial('SBD-Material-' + 'orange', material_orange, true);
var sphereMesh =
         new THREE.Mesh(
                new THREE.SphereGeometry(niceRadius, 20),
                material_orange);
var sphereModel = new THREE.Object3D();
sphereModel.add(sphereMesh);
sphereModel.position.set(atPoint.x, atPoint.y, atPoint.z);

this.viewer.impl.scene.add(sphereModel);
this.viewer.impl.invalidate(true);

一切都很好。球体被添加到我的模型中。 （它是黑色的，我仍然无法弄清楚为什么......）但最大的问题是我无法点击球体。单击它会选择模型中的底层对象，通常是墙壁或地板。

是否需要使用 RayTrace 方法来获取场景中的对象？或者对象/网格/材质是否有一个属性可以使其可点击？观众更新？

Answer 1

此时，您必须创建一个继承Autodesk.Viewing.ToolInterface 的自有工具，并将您的点击逻辑放入handleSingleClick 函数中。下面是这个案例的一个例子：

1. 自定义工具：

   class CustomTool extends Autodesk.Viewing.ToolInterface {
       constructor( viewer ) {
           super();
           this._viewer = viewer;
           this._active = false;
           this._names = [ 'CustomTool' ];
       }
   
       get viewer() {
           return this._viewer;
       }
   
       isActive() {
           return this._active;
       }
   
       handleSingleClick( event, button ) {
           const _viewer = this.viewer;
           const intersectObjects = (function () {
               const pointerVector = new THREE.Vector3();
               const pointerDir = new THREE.Vector3();
               const ray = new THREE.Raycaster();
               const camera = _viewer.impl.camera;
   
               return function(pointer, objects, recursive) {
                   const rect = _viewer.impl.canvas.getBoundingClientRect();
                   const x = (( pointer.clientX - rect.left) / rect.width ) * 2 - 1;
                   const y = - (( pointer.clientY - rect.top) / rect.height ) * 2 + 1;
   
                   if (camera.isPerspective) {
                       pointerVector.set( x, y, 0.5 );
                       pointerVector.unproject( camera );
                       ray.set( camera.position, pointerVector.sub( camera.position ).normalize() );
                   } else {
                       pointerVector.set( x, y, -1 );
                       pointerVector.unproject( camera );
                       pointerDir.set( 0, 0, -1 );
                       ray.set( pointerVector, pointerDir.transformDirection( camera.matrixWorld ) );
                   }
   
                   const intersections = ray.intersectObjects( objects, recursive );
                   return intersections[0] ? intersections[0] : null;
               };
           })();
   
           const pointer = event.pointers ? event.pointers[ 0 ] : event;
           // Intersect objects in the scene
           const result = intersectObjects( pointer, _viewer.impl.scene.children );
   
           if( result && result.object ) {
               const mesh = result.object;
               // Change object color
               let curColor = mesh.material.color;
               curColor = ( curColor.getHex() == 0xff0000 ? 0x00ff00 : 0xff0000 );
               mesh.material.color.setHex( curColor );
   
               // Refreah viewport
               this.viewer.impl.invalidate( false, true, true );
           }
   
           return false;
       }
   }
   

2. 查看器扩展管理此自定义工具：

   class CustomToolExtension extends Autodesk.Viewing.Extension {
       constructor( viewer, options ) {
           super( viewer, options );
           this._tool = undefined;
       }
   
       load() {
           // Construct an custom Tool instance
           this._tool = new CustomTool( this.viewer );
           // Register custom Tool into viewer.toolController
           this.viewer.toolController.registerTool( this._tool );
           // Activate the Tool
           this.viewer.toolController.activateTool( 'CustomTool' );
   
           return true;
       }
   
       unload() {
           // If tool has been activated, deactivate the tool.
           if( this._tool.isActive() ) {
               this.viewer.toolController.deactivateTool( 'CustomTool' );
           }
          // Deregister custom Tool 
           this.viewer.toolController.deregisterTool( this._tool );
   
           return true;
       }
   }
   
   Autodesk.Viewing.theExtensionManager.registerExtension( 'Autodesk.ADN.Sample.CustomToolExtension', CustomToolExtension );
   

希望对您有所帮助。