使UI元素跟随摄像机

Question

我想使菜单跟随摄像机，因此当用户凝视菜单时，可以触发菜单。

我参考FirstPersonCamera功能中的主相机Update来设置菜单的位置，

menuCanvas.transform.position = FirstPersonCamera.transform.position 
                               +(FirstPersonCamera.transform.forward * 4);

不幸的是，菜单始终位于相机中心，因此始终会被触发。如何正确放置上下文菜单？

Answer 1

您可以使用Vector3.Lerp进行移动[[平滑（对于较远距离的对象，运动较快，对于较短距离的对象，运动较慢）。

然后，您可以将目标位置限制为不在显示器的中央，而是在每个方向上都可以偏移。一个非常简单的示例可能看起来像

// how far to stay away fromt he center
public float offsetRadius = 0.3f;
public float distanceToHead = 4;

public Camera FirstPersonCamera;

// This is a value between 0 and 1 where
// 0 object never moves
// 1 object jumps to targetPosition immediately
// 0.5 e.g. object is placed in the middle between current and targetPosition every frame
// you can play around with this in the Inspector
[Range(0, 1)]
public float smoothFactor = 0.5f;

private void Update()
{
    // make the UI always face towards the camera
    transform.rotation = FirstPersonCamera.transform.rotation;

    var cameraCenter = FirstPersonCamera.transform.position + FirstPersonCamera.transform.forward * distanceToHead;

    var currentPos = transform.position;

    // in which direction from the center?
    var direction = currentPos - cameraCenter;

    // target is in the same direction but offsetRadius
    // from the center
    var targetPosition = cameraCenter + direction.normalized * offsetRadius;

    // finally interpolate towards this position
    transform.position = Vector3.Lerp(currentPos, targetPosition, smoothFactor);
}

当然，这远非完美，但我希望这是一个很好的起点。
moe复合物/完全溶液可以例如在MixedRealityToolkit中找到：SphereBasedTagalong
SphereBasedTagalong