可视化Raycaster

Question

我正在尝试使用光线投射来检测交叉点。我目前的问题是，我不确定我的光线投射目标是想要的方向。所以我一般的问题是:有没有一种方法可以让光线投射可见？如果是这样的话:它是如何做到的？这会对我有很大帮助。

迈克尔

Answer 1

你为什么不从原点到光线的方向画一条线呢？

更具体地说(使用r83)：

    // Draw a line from pointA in the given direction at distance 100
    var pointA = new THREE.Vector3( 0, 0, 0 );
    var direction = new THREE.Vector3( 10, 0, 0 );
    direction.normalize();

    var distance = 100; // at what distance to determine pointB

    var pointB = new THREE.Vector3();
    pointB.addVectors ( pointA, direction.multiplyScalar( distance ) );

    var geometry = new THREE.Geometry();
    geometry.vertices.push( pointA );
    geometry.vertices.push( pointB );
    var material = new THREE.LineBasicMaterial( { color : 0xff0000 } );
    var line = new THREE.Line( geometry, material );
    scene.add( line );

代码来源：https://codepen.io/anon/pen/evNqGy

Answer 2

这是另一种显示你的光线投射的方法：

scene.add(new THREE.ArrowHelper(raycaster.ray.direction, raycaster.ray.origin, 300, 0xff0000) );