用手指触摸旋转3D对象Unity 3D

Question

I want to rotate a ball when swiping left & right anywhere on the screen, so I made the script bellow, but the ball is rotating only when I swipe directly on the ball not anywhere on the screen, do you have any idea?

Ball Script:

 private float baseAngle = 0.0f;
public Camera cam;

void OnMouseDown()
{
    Vector3 pos = cam.WorldToScreenPoint(transform.position);
    pos = Input.mousePosition - pos;
    baseAngle = Mathf.Atan2(pos.y, pos.x) * Mathf.Rad2Deg;
    baseAngle -= Mathf.Atan2(transform.right.y, transform.right.x) * Mathf.Rad2Deg;
}

void OnMouseDrag()
{
    Vector3 pos = cam.WorldToScreenPoint(transform.position);
    pos = Input.mousePosition - pos;
    float ang = Mathf.Atan2(pos.y, pos.x) * Mathf.Rad2Deg - baseAngle;
    transform.rotation = Quaternion.AngleAxis(-ang, Vector3.up);
}

Answer 1

Your trouble is that the script you provided is attached to the ball itself, so touches (clicks) are processed only by the ball. In other word methods OnMouseDown and OnMouseDrag are called only when the touch(click) hits the ball. See the Documentation . It says:

OnMouseDown is called when the user has pressed the mouse button while over the GUIElement or Collider.

There are at least to ways to get what you want:

• If you want to get touched everywhere on the screen create a separate gameobject (empty and containing only a collider and your script) and make it collider Bounds fit the screen. Then add a public transform field to your script and assign the ball's transform to make it possible to rotate ball from the other script
• Use methods from Input class instead of OnMouseDown and OnMouseDrag . For example Input.GetMouseButton - it is called every time user click mouse button ( or touch) no matter, what click hit.