Question

所以这是我的问题，因为我在项目中使用三个j，用户给出x y坐标，在三个js场景上添加一个点，我需要计算碰撞对象在后面/前面的位置这一点。我尝试使用Raycaster，但我找不到一个简单的示例，说明如何将Raycaster与由point定义的向量一起使用：/ 到目前为止这是我的代码

var projector = new THREE.Projector();
    var directionVector = new THREE.Vector3();
     /* how could i use a vector defined by my origin point

     var origin = new THREE.Vector3(x, y, 0 );

     instead of the camera vector as used below ? 
     */
     projector.unprojectVector(directionVector, camera);
     directionVector.sub(camera.position);
     directionVector.normalize();
     var ray = new THREE.Raycaster();
     ray.set(camera.position,directionVector)
     var intersects = ray.intersectObjects(scene.children);
        if (intersects.length > 0) {
            console.log(intersects);
        }

Answer 1

要从任意点进行光线投射，您可以使用此模式：

var raycaster = new THREE.Raycaster(); // create once, and reuse
var origin = new THREE.Vector3(); // reuse it
var direction = new THREE.Vector3(); // reuse it
...

origin.set( x, y, z );
direction.set( 0, 0, - 1 ).normalize(); // direction vector must have unit length
raycaster.set( origin, direction );
var intersects = raycaster.intersectObjects( objects, recursiveFlag );
if ( intersects.length > 0 ) {      
    // your code        
}

three.js r.75

如何从任意点进行Raycast

1 个答案: