可視化Raycaster

Question

我想通過使用raycast檢測交叉點。我目前的問題是，我不確定我的光線瞄準的方向是什麼。所以我的一般問題是：有沒有辦法讓光線投射可見？如果是這樣：它是如何完成的？這會幫助我很多。

邁克爾

Answer 1

你爲什麼不從原點畫一條線到線的方向。

更具體地（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); 

Codepen在：https://codepen.io/anon/pen/evNqGy