多个光线投射，只有两个在工作

Question

我正在开发一个 AI，我想给它提供玩家（汽车）与游戏中（几乎）所有其他东西（墙壁、街道中间、其他汽车）之间的距离。我正在使用 Physics.Raycast。问题是只有 DistanceToRightSideOfMOTS (MOTS: middle of the street) 和 DistanceToBackWall 有效。这是我的代码：

private void FixedUpdate()
{
    RequestDecision();
    RequestAction();

     // Get the distances to the walls

    // Get distance to left wall
    RaycastHit hit;
    if (Physics.Raycast(transform.position, transform.TransformDirection(Vector3.left), out hit, 25, 1 << 11))
    {
        DistanceToLeftWall = hit.distance / 25;
        Debug.DrawRay(transform.position, transform.TransformDirection(Vector3.left) * hit.distance, Color.red);
    }
    else
    {
        DistanceToLeftWall = 1;
    }

    // Get distance to right wall
    if (Physics.Raycast(transform.position, transform.TransformDirection(Vector3.right), out hit, 25, 1 << 12))
    {
        DistanceToRightWall = hit.distance / 25;
        Debug.DrawRay(transform.position, transform.TransformDirection(Vector3.right) * hit.distance, Color.red);
    }
    else
    {
        DistanceToRightWall = 1;
    }

    // Get distance to front wall (it sees 2x farther because it's hard to turn on the corner)
    if (Physics.Raycast(transform.position, transform.TransformDirection(Vector3.forward), out hit, 50, (1 << 11) | (1 << 12)))
    {
        DistanceToFrontWall = hit.distance / 50;
        Debug.DrawRay(transform.position, transform.TransformDirection(Vector3.forward) * hit.distance, Color.red);
    }
    else
    {
        DistanceToFrontWall = 1;
    }
    // Get distance to back wall
    if (Physics.Raycast(transform.position, transform.TransformDirection(Vector3.back), out hit, 50, (1 << 11) | (1 << 12)))
    {
        DistanceToBackWall = hit.distance / 50;
        Debug.DrawRay(transform.position, transform.TransformDirection(Vector3.back) * hit.distance, Color.red);
    }
    else
    {
        DistanceToBackWall = 1;
    }

    //////////////////

    // Get the distance to other cars

    /////////////////

    // Get distance to left car
    if (Physics.Raycast(transform.position, transform.TransformDirection(Vector3.left), out hit, 25, 1 << 13))
    {
        DistanceToLeftCar = hit.distance / 25;
        Debug.DrawRay(transform.position, transform.TransformDirection(Vector3.left) * hit.distance, Color.green);
    }
    else
    {
        DistanceToLeftCar = 1;
    }

    // Get distance to right car
    if (Physics.Raycast(transform.position, transform.TransformDirection(Vector3.right), out hit, 25, 1 << 13))
    {
        DistanceToRightCar = hit.distance / 25;
        Debug.DrawRay(transform.position, transform.TransformDirection(Vector3.right) * hit.distance, Color.green);
    }
    else
    {
        DistanceToRightCar = 1;
    }

    // Get distance to front car
    if (Physics.Raycast(transform.position, transform.TransformDirection(Vector3.forward), out hit, 50, 1 << 13))
    {
        DistanceToFrontCar = hit.distance / 50; // We divide the distance to normalize the input
        Debug.DrawRay(transform.position, transform.TransformDirection(Vector3.forward) * hit.distance, Color.green);
    }
    else
    {
        DistanceToFrontCar = 1;
    }
    // Get distance to back car
    if (Physics.Raycast(transform.position, transform.TransformDirection(Vector3.back), out hit, 50, 1 << 13))
    {
        DistanceToBackCar = hit.distance / 50;
        Debug.DrawRay(transform.position, transform.TransformDirection(Vector3.back) * hit.distance, Color.green);
    }
    else
    {
        DistanceToBackCar = 1;
    }


    //Get distances to the middle of the street


    //Get distance from the left side
    if (Physics.Raycast(transform.position, transform.TransformDirection(Vector3.left), out hit, 10, 1 << 14))
    {
        DistanceToLeftSideOfMOTS = hit.distance / 10;
        Debug.DrawRay(transform.position, transform.TransformDirection(Vector3.left) * hit.distance, Color.blue);
    }
    else
    {
        DistanceToLeftSideOfMOTS = 1;
    }
    //Get distance from the right side
    if (Physics.Raycast(transform.position, transform.TransformDirection(Vector3.right), out hit, 10, 1 << 14))
    {
        DistanceToRightSideOfMOTS = hit.distance / 10;
        Debug.DrawRay(transform.position, transform.TransformDirection(Vector3.right) * hit.distance, Color.blue);
    }
    else
    {
        DistanceToRightSideOfMOTS = 1;
    }

}

其他距离总是返回 1，即使它不应该。为什么不起作用，我该如何解决？

Edit1：我不知道为什么，但是当我将汽车超靠近右墙时，DistanceToRightWall 开始工作，而 DistanceToBackCar 仅在我离汽车至少 15m 时才有效。有没有其他选择？

Edit2：我在墙壁和街道中间使用了平面。当我查看物理调试可视化时，我从一侧看到了平面对撞机，但从另一侧看不到。我是 Unity 新手，所以也许这可能是问题所在。

Edit3：我在街道中间添加了一个盒子碰撞器，DistanceToLeftSideOfMOTS 开始工作，但我尝试用墙壁来做，但没有成功。

Edit4：我把盒子对撞机做得更大，而且效果很好。现在唯一的问题是汽车。

Answer 1

我构建了一个示例场景来试用您的代码，但找不到任何问题。确保您的汽车对象方向正确，并且墙壁和汽车具有适当的图层和分配给它们的碰撞器。 Unity 的Physics Debug Visualization 可能会有所帮助。

另外，最好多保留一点DRY。例如，您可以将所有 raycast 调用移动到一个方法中以减少重复。这样一来，如果出现问题，可以查看的地方就更少了：

private void FixedUpdate()
{
    RequestDecision();
    RequestAction();
    UpdateWallDistances();
}

private void UpdateWallDistances()
{
    int leftWallMask = 1 << 11;
    int rightWallMask = 1 << 12;
    int wallMask = leftWallMask | rightWallMask;
    int carMask = 1 << 13;
    int middleOfStreetMask = 1 << 14;

    // Get the distances to the walls
    DistanceToLeftWall = GetDistance(Vector3.left, 25, leftWallMask, Color.red);
    DistanceToRightWall = GetDistance(Vector3.right, 25, rightWallMask, Color.red);
    DistanceToFrontWall = GetDistance(Vector3.forward, 50, wallMask, Color.red);
    DistanceToBackWall = GetDistance(Vector3.back, 50, wallMask, Color.red);

    // Get the distance to other cars
    DistanceToLeftCar = GetDistance(Vector3.left, 25, carMask, Color.green);
    DistanceToRightCar = GetDistance(Vector3.right, 25, carMask, Color.green);
    DistanceToFrontCar = GetDistance(Vector3.forward, 50, carMask, Color.green);
    DistanceToBackCar = GetDistance(Vector3.back, 50, carMask, Color.green);

    //Get distances to the middle of the street
    DistanceToLeftSideOfMOTS = GetDistance(Vector3.left, 10, middleOfStreetMask, Color.blue);
    DistanceToRightSideOfMOTS = GetDistance(Vector3.right, 10, middleOfStreetMask, Color.blue);
}

private float GetDistance(Vector3 direction, float maxDistance, int layerMask, Color debugColor)
{
    RaycastHit hit;
    if (Physics.Raycast(transform.position, transform.TransformDirection(direction), out hit, maxDistance, layerMask))
    {
        Debug.DrawRay(transform.position, transform.TransformDirection(direction) * hit.distance, debugColor);
        return hit.distance / maxDistance;
    }
    else
    {
        return 1;
    }
}