Question

我正在进行简单的碰撞检测，虽然我可以使用THREE.ray轻松检测上/下物体，但我很难在旋转时找到相机（或任何物体）前/后的内容？我尝试使用投影仪投射光线，并使用辅助箭头显示光线的射击方式。一旦我开始围绕Y轴旋转相机，光线指向反方向或只是奇怪地行动......

ray = new THREE.Ray();
projector = new THREE.Projector();
vector = projector.projectVector( coll.getObject().matrix.getPosition().clone(), camera );
ray.direction = vector.normalize();
ray.origin = coll.getObject().matrix.getPosition().clone();
helper.setDirection(ray.direction.clone());
helper.position = ray.origin.clone();

Answer 1

我最终设置了一个围绕我的物体的立方体连接到相机并通过顶点拍摄光线，如下所示：

vertices = coll.getObject().geometry.vertices;
        rad = coll.getObject().boundRadius+1;
        var directions = {
            "up": [4,1],
            "down": [6,2],
            "front": [3,4],
            "back": [7,0],
            "left": [5,6],
            "right": [1,2],
        };
        var collisions = {
            "up": {},
            "down": {},
            "front": {},
            "back": {},
            "left": {},
            "right": {},
        };
        for (key in directions){
            (directions[key].length > 1) ? localVertex =  vertices[directions[key][0]].clone().addSelf(vertices[directions[key][1]].clone()) : localVertex = vertices[directions[key][0]].clone();  
            globalVertex = coll.getObject().matrix.multiplyVector3(localVertex);
            directionVector = globalVertex.subSelf( coll.getObject().position );
            ray = new THREE.Ray( coll.getObject().position.clone(), directionVector.clone().normalize(), 0, 1000 );
            intersects = ray.intersectObjects(obj, true);
            if (intersects.length > 0) {
                distance = intersects[ 0 ].distance;
                if (distance >= 0 && distance <= rad) {
                    collisions[key] = intersects[ 0 ];              
                } else {                        
                    collisions[key] = false;
                }
            } else {
                collisions[key] = false;
                ++falseCount;
            }       
        }                   
    }
    return (falseCount !== 6) ? collisions : false;

相机（对象）正在观看的Ray.direction

1 个答案: