Three.js，PointerLock和冲突检测 [英] Three.js, PointerLock And Collision Detection

问题描述

我正在研究3d虚拟家庭项目。一切正常，除了碰撞检测。
我将PointerLockControls用于相机和移动。但我不确定如何在所有可能的方向上检测碰撞。
为简单起见，我从与（0,0,0）上的简单立方体的向前和向后碰撞开始：

I'm working on a 3d virtual home project. everythings works fine except collision detection. I use PointerLockControls for my camera and movement. but i'm not sure how to detec collision in every possible directions. For simplicity i started with just forward and backward collision to a simple cube on (0,0,0):

rays = [
    new THREE.Vector3(0, 0, 1),
    new THREE.Vector3(0, 0, -1)
];

然后：

function detectCollision() {
var vector;
var projector = new THREE.Projector();

for (var i = 0; i < rays.length; i++) {
    var vector = rays[i].clone();
    projector.unprojectVector(vector, camera);

    var rayCaster = new THREE.Raycaster(controls.getObject().position, vector.sub(controls.getObject().position).normalize());
    var intersects = rayCaster.intersectObject(cube, true);

    if (intersects.length > 0 && intersects[0].distance < 50) {
        console.log(vector);
        console.log(i, intersects);
        $("#status").text("Collision detected @ " + rays[i].x + "," + rays[i].z +
            "<br \>" + intersects[0].distance);
    }
}

但是当我离立方体足够近时，控制台告诉我两条光线都射中了立方体！所以为什么？
我的光线有问题吗？ vector（0,0,1）应该向后，而（0,0，-1）应该向后，对吗？
在我迷失3D之前，请帮助我！
谢谢。

But when i get close enough to my cube, console shows me both rays hit the cube! so why? Is there any problem with my rays? vector(0,0,1) should be backward and (0,0,-1) should be forward, right? Please help me, before i get lost in 3d! Thanks.

推荐答案

最后我发现了！解决方案。我不擅长数学，但最后我弄清楚了。

从指针锁控件获得方向后，取决于所按下的键，我将方向放入旋转矩阵中获取实际的方向矢量（感谢Icemonster的提示）：

Finally i discovered!! the solution. i'm not good at math, but at the end i figure it out.
After i get direction from pointer-locker controls, depend on which key is pressed, i put the direction into a rotation matrix to get the actual direction vector(thanks for the clue Icemonster):

function detectCollision() {
unlockAllDirection();

var rotationMatrix;
var cameraDirection = controls.getDirection(new THREE.Vector3(0, 0, 0)).clone();

if (controls.moveForward()) {
    // Nothing to do!
}
else if (controls.moveBackward()) {
    rotationMatrix = new THREE.Matrix4();
    rotationMatrix.makeRotationY(180 * Math.PI / 180);
}
else if (controls.moveLeft()) {
    rotationMatrix = new THREE.Matrix4();
    rotationMatrix.makeRotationY(90 * Math.PI / 180);
}
else if (controls.moveRight()) {
    rotationMatrix = new THREE.Matrix4();
    rotationMatrix.makeRotationY((360-90) * Math.PI / 180);
}
else return;

if (rotationMatrix !== undefined){
    cameraDirection.applyMatrix4(rotationMatrix);
}
var rayCaster = new THREE.Raycaster(controls.getObject().position, cameraDirection);    
var intersects = rayCaster.intersectObject(hitMesh, true);  

$("#status").html("camera direction x: " + cameraDirection.x + " , z: " + cameraDirection.z);

if ((intersects.length > 0 && intersects[0].distance < 25)) {
    lockDirection();
    $("#status").append("<br />Collision detected @ " + intersects[0].distance);

    var geometry = new THREE.Geometry();
    geometry.vertices.push(intersects[0].point);
    geometry.vertices.push(controls.getObject().position);
    scene.remove(rayLine);
    rayLine = new THREE.Line(geometry, new THREE.LineBasicMaterial({color: 0xFF00FF, linewidth: 2}));
    scene.add(rayLine);
}
}

我也对PointerLockControls.js进行了一些更改，相机碰到对撞机对象时停止移动。我在此处上传示例： CameraRayCasting.zip

Also i made some changes to the PointerLockControls.js to stop moving when camera hit the collider object. I upload my sample here: CameraRayCasting.zip

更新

最后，我找到了一些时间来完成我的TouchControls项目。它使用threejs v0.77.1并支持触摸和命中测试。

在此处查看： TouchControls

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