一个Three.js raycaster可以与一组相交吗？

Question

我想知道我的raycaster是否在看我装的OBJ.由于从Cinema4D导出的方式,我相信OBJ是一个有3个孩子的THREE.Group,而不是THREE.Object.我可以只更改我的raycaster代码行来查找该组而不是对象吗？

raycaster.set(controls.getObject().position, controls.getDirection(), 0, 40)

var intersects = raycaster.intersectObjects(scene.children, true);

     if (intersects.length > 0) {
      //CURRENTLY INTERSECTING SOMETHING
      for (var i = 0; i < onOffCubes.length; i++) {
      //if the first thing the raycaster sees is a one of my cubes
        if (intersects[0].object == onOffCubes[i]) {
                ExperiencesData[i].userClose = true
            }
         }
       }

onOffCubes是一个包含6个OBJ/THREE.js组的数组:

Console.log(onOffCubes [0])是这样的:

Answer 1

很近.交叉对象是网格,该网格的父级是该组.您需要匹配交叉的父对象而不是交叉的对象.那是:

intersects[ 0 ].object.parent === onOffCubes[ i ]

而不是:

intersects[ 0 ].object === onOffCubes[ i ]

TL; DR

为了测试类似的结构,我生成了六组,每组三个网格,每组网格共享相同的材料.请注意,onOffCubes不是THREE.js组,它是一组组.这就像原始海报上的onOffCubes:

var onOffCubes = []
for ( var i = 0; i < 6; i++ ) {
    var material = new THREE.MeshBasicMaterial({ color: 0xee55aa })
    var group = new THREE.Group()
    for ( var j = 0; j < 3; j++ ) {
        var mesh = new THREE.Mesh( geometry, material );
        mesh.position.x = Math.random() * 100 - 50;
        mesh.position.y = Math.random() * 100 - 50;
        mesh.position.z = Math.random() * 200 - 200;
        group.add( mesh );
    }
    onOffCubes.push( group )
    scene.add( group )
}

检查完整场景

var intersects = raycaster.intersectObjects( scene.children, true );

或只检查onOffCubes

var intersects = raycaster.intersectObjects( onOffCubes, true );

基本上与原始海报相同的代码与一个修复:

if (intersects.length > 0) {
    for (var i = 0; i < onOffCubes.length; i++) { 
        if (intersects[ 0 ].object.parent === onOffCubes[ i ]) {
            // What I tested with
            //intersects[ 0 ].object.material.color.set( 0xff0000 )
            // Your code
            ExperiencesData[i].userClose = true
        }
    }
}

Answer 2

试着看看你小组的孩子：

var intersects = raycaster.intersectObjects(YOUR_OBJECT.children, true);

THREE.Group 继承自 THREE.Object3D，所以它可以工作