/// <summary>
/// Initializes the GestureTouchesUtility singleton if needed and returns a valid instance.
/// </summary>
/// <returns>The instance of GestureTouchesUtility.</returns>
private static GestureTouchesUtility _GetInstance()
{
if (s_Instance == null)
{
s_Instance = new GestureTouchesUtility();
}
return(s_Instance);
}
/// <summary>
/// Helper function for creating one finger gestures when a touch begins.
/// </summary>
/// <typeparam name="createGestureFunction">Function to be executed to create the
/// gesture.</param>
protected internal void TryCreateOneFingerGestureOnTouchBegan(
Func <Touch, T> createGestureFunction)
{
for (int i = 0; i < Input.touches.Length; i++)
{
Touch touch = Input.touches[i];
if (touch.phase == TouchPhase.Began &&
!GestureTouchesUtility.IsFingerIdRetained(touch.fingerId) &&
!GestureTouchesUtility.IsTouchOffScreenEdge(touch))
{
T gesture = createGestureFunction(touch);
gesture.onStart += OnStart;
gesture.onFinished += OnFinished;
m_Gestures.Add(gesture);
}
}
}
private void TryCreateGestureTwoFingerGestureOnTouchBeganForTouchIndex(
int touchIndex,
Func <Touch, Touch, T> createGestureFunction)
{
if (Input.touches[touchIndex].phase != TouchPhase.Began)
{
return;
}
Touch touch = Input.touches[touchIndex];
if (GestureTouchesUtility.IsFingerIdRetained(touch.fingerId) ||
GestureTouchesUtility.IsTouchOffScreenEdge(touch))
{
return;
}
for (int i = 0; i < Input.touches.Length; i++)
{
if (i == touchIndex)
{
continue;
}
// Prevents the same two touches from creating two gestures if both touches began on
// the same frame.
if (i < touchIndex && Input.touches[i].phase == TouchPhase.Began)
{
continue;
}
Touch otherTouch = Input.touches[i];
if (GestureTouchesUtility.IsFingerIdRetained(otherTouch.fingerId) ||
GestureTouchesUtility.IsTouchOffScreenEdge(otherTouch))
{
continue;
}
T gesture = createGestureFunction(touch, otherTouch);
gesture.onStart += OnStart;
gesture.onFinished += OnFinished;
m_Gestures.Add(gesture);
}
}
/// <summary>
/// Calculates the best position to place an object in AR based on screen position.
/// Could be used for tapping a location on the screen, dragging an object, or using a fixed
/// cursor in the center of the screen for placing and moving objects.
///
/// Objects are placed along the x/z of the grounding plane. When placed on an AR plane
/// below the grounding plane, the object will drop straight down onto it in world space.
/// This prevents the object from being pushed deeper into the scene when moving from a
/// higher plane to a lower plane. When moving from a lower plane to a higher plane, this
/// function returns a new groundingPlane to replace the old one.
/// </summary>
/// <returns>The best placement position.</returns>
/// <param name="currentAnchorPosition">Position of the parent anchor, i.e., where the
/// object is before translation starts.</param>
/// <param name="screenPos">Location on the screen in pixels to place the object at.</param>
/// <param name="groundingPlaneHeight">The starting height of the plane that the object is
/// being placed along.</param>
/// <param name="hoverOffset">How much should the object hover above the groundingPlane
/// before it has been placed.</param>
/// <param name="maxTranslationDistance">The maximum distance that the object can be
/// translated.</param>
/// <param name="translationMode">The translation mode, indicating the plane types allowed.
/// </param>
public static Placement GetBestPlacementPosition(
Vector3 currentAnchorPosition,
Vector2 screenPos,
float groundingPlaneHeight,
float hoverOffset,
float maxTranslationDistance,
TranslationMode translationMode)
{
Placement result = new Placement();
result.UpdatedGroundingPlaneHeight = groundingPlaneHeight;
// Get the angle between the camera and the object's down direction.
float angle = Vector3.Angle(Camera.main.transform.forward, Vector3.down);
angle = 90.0f - angle;
float touchOffsetRatio = Mathf.Clamp01(angle / 90.0f);
float screenTouchOffset = touchOffsetRatio * k_MaxScreenTouchOffset;
screenPos.y += GestureTouchesUtility.InchesToPixels(screenTouchOffset);
float hoverRatio = Mathf.Clamp01(angle / 45.0f);
hoverOffset *= hoverRatio;
float distance = (Camera.main.transform.position - currentAnchorPosition).magnitude;
float distanceHoverRatio = Mathf.Clamp01(distance / k_HoverDistanceThreshold);
hoverOffset *= distanceHoverRatio;
// The best estimate of the point in the plane where the object will be placed:
Vector3 groundingPoint;
// Get the ray to cast into the scene from the perspective of the camera.
TrackableHit hit;
if (Frame.Raycast(
screenPos.x, screenPos.y, TrackableHitFlags.PlaneWithinBounds, out hit))
{
if (hit.Trackable is DetectedPlane)
{
DetectedPlane plane = hit.Trackable as DetectedPlane;
if (IsPlaneTypeAllowed(translationMode, plane.PlaneType))
{
// Avoid detecting the back of existing planes.
if ((hit.Trackable is DetectedPlane) &&
Vector3.Dot(Camera.main.transform.position - hit.Pose.position,
hit.Pose.rotation * Vector3.up) < 0)
{
Debug.Log("Hit at back of the current DetectedPlane");
return(result);
}
// Don't allow hovering for vertical or horizontal downward facing planes.
if (plane.PlaneType == DetectedPlaneType.Vertical ||
plane.PlaneType == DetectedPlaneType.HorizontalDownwardFacing)
{
// Limit the translation to maxTranslationDistance.
groundingPoint = LimitTranslation(
hit.Pose.position, currentAnchorPosition, maxTranslationDistance);
result.PlacementPlane = hit;
result.PlacementPosition = groundingPoint;
result.HoveringPosition = groundingPoint;
result.UpdatedGroundingPlaneHeight = groundingPoint.y;
result.PlacementRotation = hit.Pose.rotation;
return(result);
}
// Allow hovering for horizontal upward facing planes.
if (plane.PlaneType == DetectedPlaneType.HorizontalUpwardFacing)
{
// Return early if the camera is pointing upwards.
if (angle < 0f)
{
return(result);
}
// Limit the translation to maxTranslationDistance.
groundingPoint = LimitTranslation(
hit.Pose.position, currentAnchorPosition, maxTranslationDistance);
// Find the hovering position by casting from the camera onto the
// grounding plane and offsetting the result by the hover offset.
result.HoveringPosition = groundingPoint + (Vector3.up * hoverOffset);
// If the AR Plane is above the grounding plane, then the hit plane's
// position is used to replace the current groundingPlane. Otherwise,
// the hit is ignored because hits are only detected on lower planes by
// casting straight downwards in world space.
if (groundingPoint.y > groundingPlaneHeight)
{
result.PlacementPlane = hit;
result.PlacementPosition = groundingPoint;
result.UpdatedGroundingPlaneHeight = hit.Pose.position.y;
result.PlacementRotation = hit.Pose.rotation;
return(result);
}
}
else
{
// Not supported plane type.
return(result);
}
}
else
{
// Plane type not allowed.
return(result);
}
}
else
{
// Hit is not a plane.
return(result);
}
}
// Return early if the camera is pointing upwards.
if (angle < 0f)
{
return(result);
}
// If the grounding point is lower than the current gorunding plane height, or if the
// raycast did not return a hit, then we extend the grounding plane to infinity, and do
// a new raycast into the scene from the perspective of the camera.
Ray cameraRay = Camera.main.ScreenPointToRay(screenPos);
Plane groundingPlane =
new Plane(Vector3.up, new Vector3(0.0f, groundingPlaneHeight, 0.0f));
// Find the hovering position by casting from the camera onto the grounding plane
// and offsetting the result by the hover offset.
float enter;
if (groundingPlane.Raycast(cameraRay, out enter))
{
groundingPoint = LimitTranslation(
cameraRay.GetPoint(enter), currentAnchorPosition, maxTranslationDistance);
result.HoveringPosition = groundingPoint + (Vector3.up * hoverOffset);
}
else
{
// If we can't successfully cast onto the groundingPlane, just return early.
return(result);
}
// Cast straight down onto AR planes that are lower than the current grounding plane.
if (Frame.Raycast(
groundingPoint + (Vector3.up * k_DownRayOffset), Vector3.down,
out hit, Mathf.Infinity, TrackableHitFlags.PlaneWithinBounds))
{
result.PlacementPosition = hit.Pose.position;
result.PlacementPlane = hit;
result.PlacementRotation = hit.Pose.rotation;
return(result);
}
return(result);
}
