SpringPanel.onFinished sometimes very late

[Gregzo]

Hi,

I'm having a rare issue where SpringPanel's onFinished delegate does not fire immediately when UICenterOnChild has finished centering, sometimes by as much as 10 seconds.
It doesn't happen often, I have to test for some times as much as 10 minutes for the bug to show up, but it's very much there.

Then again, it might be me : I'm using a modified version of UICenterOnChild.

Any help appreciated!

UICenterOnChildManual.cs :

1. public class UICenterOnChildManual : MonoBehaviour
2. {
3.         UIDraggablePanel mDrag;
4.         GameObject mCenteredObject;
5.        
6.         public SpringPanel.OnFinished onFinished;
7.        
8.         void Awake ()
9.         {
10.                 mDrag = gameObject.GetComponent ( typeof ( UIDraggablePanel ) ) as UIDraggablePanel;
11.                 //Test
12.                 onFinished += Test; // for debugging purposes
13.         }
14.        
15.         /// <summary>
16.         /// Recenter the draggable panel on targetTrans.
17.         /// </summary>
18.  
19.         public void CenterOnChild( Transform targetTrans )
20.         {
21.                 Debug.Log ("CenterOnChild called at "+Time.time);
22.                
23.                 if (mDrag.panel == null) return;
24.                 // Calculate the panel's center in world coordinates
25.                 Vector4 clip = mDrag.panel.clipRange;
26.                 Transform dt = mDrag.panel.cachedTransform;
27.                 Vector3 center = dt.localPosition;
28.                 center.x += clip.x;
29.                 center.y += clip.y;
30.                 center = dt.parent.TransformPoint(center);
31.  
32.                 // Offset this value by the momentum
33.                 mDrag.currentMomentum = Vector3.zero;
34.  
35.                 // Figure out the difference between the chosen child and the panel's center in local coordinates
36.                 Vector3 cp = dt.InverseTransformPoint(targetTrans.position);
37.                 Vector3 cc = dt.InverseTransformPoint(center);
38.                 Vector3 offset = cp - cc;
39.  
40.                 // Offset shouldn't occur if blocked by a zeroed-out scale
41.                 if (mDrag.scale.x == 0f) offset.x = 0f;
42.                 if (mDrag.scale.y == 0f) offset.y = 0f;
43.                 if (mDrag.scale.z == 0f) offset.z = 0f;
44.  
45.                 // Spring the panel to this calculated position
46.                 SpringPanel.Begin(mDrag.gameObject, dt.localPosition - offset, 8f).onFinished = onFinished;
47.         }
48.        
49.         void Test ()
50.         {
51.                 Debug.Log ("SpringPanel finished at "+Time.time);
52.         }
53. }

[MGB]

I've had this happen too... seems to be worse on faster machines.
Possibly some problem in SpringLerp integration..?

[ArenMook]

Might be related to the distance being too small. Look inside SpringPanel:

1. if (mThreshold >= Vector3.Magnitude(after - target))

where mThreshold is set as:

1. mThreshold = (target - mTrans.localPosition).magnitude * 0.005f;

In SpringPanel.Begin it only resets the threshold if the component is disabled, so perhaps move out the

1. sp.mThreshold = 0f;

outside that "if" statement?
You can also try changing the "if (mThreshold == 0f)" part in Update to the following:

1. if (mThreshold == 0f)
2. {
3.         mThreshold = (target - mTrans.localPosition).magnitude * 0.005f;
4.         mThreshold = Mathf.Max(mThreshold, 0.00001f);
5. }

[Gregzo]

Hi Aren,

Thanks for the tips. So far, I've designed around it ( did my own, stripped version of SpringPanel, optimized for use in my pickers. NGUI credited, of course... ).

As the bug arises in a commercial asset, can't tweak NGUI classes.

Will there still be NGUI updates, or are you racing towards the Graal of GUIs, crunching away?

Cheers,

Gregzo

[ArenMook]

If the fixes I posted resolve the issue, then they will be promoted to the live version's repository -- but someone has to test them first

NGUI isn't going anywhere. While I am indeed focusing on the upcoming GUI atm, I will still be updating NGUI.

[Gregzo]

Thanks for the reply Aren.

Unfortunately, I'm getting the bug so rarely that it is very hard to test properly. A user of NGUI Infinite Pickers reported it happened 100% of the time on his machine, and sent me the following patch that worked for him :

1. if (mThreshold >= Vector3.Magnitude(after - target) || Vector3.Magnitude(after - target) < 0.001f)

It might not be the best solution, but wth the bug occurring so rarely on my machine, it's very hard to know reliably what works and what doesn't.

Cheers,

Gregzo