void Update()
{
// See if the left mouse is down
if (!Input.GetMouseButton(0))
{
return;
}
// When they first hit the mouse down, define the click point to be along the camera look and intersecting the grab ball
bool isFirstClick = Input.GetMouseButtonDown(0);
if (isFirstClick)
{
_clickPlane = new Plane(_camera.transform.forward, transform.position);
}
Vector3 mousePos = Input.mousePosition;
Rect screenRect = new Rect(0, 0, Screen.width, Screen.height);
if (!screenRect.Contains(mousePos)) // this can happen when they start on screen and keep dragging off screen
{
return;
}
Ray ray = _camera.ScreenPointToRay(mousePos);
// Move the grab object to where the mouse ray intersects the click plane
Vector3?newPos = Math3D.GetIntersection_Plane_Ray(_clickPlane, ray);
if (newPos == null)
{
return;
}
if (isFirstClick)
{
_isSelected = (transform.position - newPos.Value).magnitude <= Math1D.Max(transform.localScale.x, transform.localScale.y, transform.localScale.z) * 1.2f;
}
if (!_isSelected)
{
return;
}
transform.position = newPos.Value;
}