Unity:使用TouchPhase.Moved时，如何停止阅读第一次触摸

Question

我有两个脚本，一个是带有以下内容的播放器控制器：

void Update () {
if (Input.touchCount > 0 && Input.GetTouch(0).phase == TouchPhase.Began)
{

Touch touch = Input.GetTouch(0);
Ray ray = cam.ScreenPointToRay(touch.position);
RaycastHit hit;
if (EventSystem.current.IsPointerOverGameObject(touch.fingerId))
{
return;
}

if (Physics.Raycast(ray, out hit, 100))
{
Interactable interactable = hit.collider.GetComponent<Interactable>();
if (interactable != null)
{
SetFocus(interactable);
}
else
{
motor.MoveToPoint(hit.point);
RemoveFocus();
}
}
}
}       

然后我的相机脚本是：

void Update()
{
currentZoom -= Input.GetAxis("Mouse ScrollWheel") * zoomSpeed;
currentZoom = Mathf.Clamp(currentZoom, minZoom, maxZoom);
currentYaw -= Input.GetAxis("Horizontal") * yawSpeed * Time.deltaTime;
if (Input.touchCount > 0 && Input.GetTouch(0).phase == TouchPhase.Moved)
{
Vector2 touchDirection = Input.GetTouch(0).deltaPosition;
if (touchDirection.x > minSwipe || touchDirection.x < -minSwipe)
{
currentYaw -= touchDirection.x * yawSpeed / mobileYawReduction * Time.deltaTime;
}
}
}
// Update is called once per frame
void LateUpdate () {
transform.position = target.position - offset * currentZoom;
transform.LookAt(target.position + Vector3.up * pitch);
transform.RotateAround(target.position, Vector3.up, currentYaw);
}

这两种方法都很好：我可以轻击角色，并在滑动时很好地旋转相机。唯一的问题是，当我滑动旋转时，它会记录触摸的开始并开始移动。我该如何避免这种情况？

Answer 1

触摸开始时不移动，而只能在触摸结束时移动，触摸过程中触摸位置没有太大变化。

如果正在触摸并且位置变化超过一点阈值，则将其解释为滑动，并在触摸结束时跳过调用目标代码块。

// if movement was greater than interpret as swipe 
public float swipeThreshold = 0.01;
Vector2 startPosition ;
float movedDistance;
Touch touch;
void Update () 
{
if (Input.touchCount <= 0) return;
switch(Input.GetTouch(0).phase)
{
case TouchPhase.Began:
// On begin only save the start position
touch = Input.GetTouch(0);
if (EventSystem.current.IsPointerOverGameObject(touch.fingerId))
{
return;
}
startPosition = touch.position;
movedDistance = 0;
break;
case TouchPhase.Moved:
// if moving check how far you moved
movedDistance = Vector2.Distance(touch.position, startPosition );
break;
case TouchPhase.Ended:
// on end of touch (like button up) check the distance
// if you swiped -> moved more than swipeThreshold
// do nothing
if(movedDistance > swipeThreshold) break;
Ray ray = cam.ScreenPointToRay(touch.position);
RaycastHit hit;
if (!Physics.Raycast(ray, out hit, 100)) break;
Interactable interactable = hit.collider.GetComponent<Interactable>();
if (interactable != null)
{
SetFocus(interactable);
}
else
{
motor.MoveToPoint(hit.point);
RemoveFocus();
}
break;
default:
break;
}
}

我会将相同的阈值添加到相机脚本中以保持一致。要么在他们之间以某种方式共享这个阈值(甚至从另一个脚本中获取(，要么简单地输入相同的值

public float swipeThreshold = 0.01;
Vector2 startPosition;
void Update()
{
currentZoom -= Input.GetAxis("Mouse ScrollWheel") * zoomSpeed;
currentZoom = Mathf.Clamp(currentZoom, minZoom, maxZoom);
currentYaw -= Input.GetAxis("Horizontal") * yawSpeed * Time.deltaTime;
if (Input.touchCount <= 0) return;
switch(Input.GetTouch(0).phase)
{
case TouchPhase.Began:
startPosition = Input.GetTouch(0).position;
break;
case TouchPhase.Moved:
// if yet not moved enough do nothing
var movedDistance = Vector2.Distance(Input.GetTouch(0).position, startPosition);
if (movedDistance <= swipeThreshold) break;
Vector2 touchDirection = Input.GetTouch(0).deltaPosition;
if (touchDirection.x > minSwipe || touchDirection.x < -minSwipe)
{
currentYaw -= touchDirection.x * yawSpeed / mobileYawReduction * Time.deltaTime;
}
break;
default:
break;
}
}