Windows 10: desktop touch issue

Unity Engine
,
1

Hi

We are currently testing our applications on Windows 10 preview builds. We discovered a problem with Windows desktop applications when it comes to touch. We have used TouchScript to handle our touches. Our Unity version is 4.5.3f3.

When executing a certain order of touches (see below), touch points get stuck in the ‘touch move’ state. The most likely reason is that the ‘touch up’ events are not registered. But it might as well be an issue in the IDs of the touch points.

To create the issue, the following actions are performed:
Touch with finger 1. Keep this finger on the screen. Touch with a number of other fingers. Keep these on the screen. Release finger 1. Touch again with finger 1. From this moment, the touch points connected to the other fingers will be stuck in the ‘touch move’ state.
Here is a movie to show the above action:

We have also tested the test app of TouchScript to be sure it is not exclusively our software.
Windows 8 Store App builds of our games do not have the issue. It is clearly related to desktop applications. We need desktop applications as our games are started from third party software.

Is this issue already known at Unity?
Are there other people experiencing this issue?
Is there a workaround?

Additional info:
We have AIR based applications which have the same issue. Indicating the problem might be originating from the Windows 10 desktop.
The problem only happens on Windows 10. Older Windows versions don’t have this issue.
A simple WPF multi touch test application (for desktop) does NOT have the problem.

Sincerely,
Jens Wouters
Developer at Omnivision Studios

2

Touches are not supported on Windows Standalone prior to 5.0, so I am not sure I understand… how are you receiving touch events on Windows Standalone, is TouchScript a plugin? If so, please contact the author.

3

TouchScript is a plugin. I have contacted the creator.

This thread is intended for people who will run into the same issue. Although the problem might not be caused by Unity, if the people use Unity for development, the Unity forums will be the first place they will look to find an answer.

We have also contacted other parties and will share the answer once we find one.

4

IMPORTANT UPDATE

I created the smallest possible test app to test the new touch support in Windows that is present in Unity 5.0.1f1. Turns out this touch has the same issue as our third party plugin we used!

The only thing my app does, is displaying the number of active touch points (Input.touchCount).

When performing the same sequence of touches as can be seen in the video (see original post) the counter will not drop to zero anymore. If you repeat the sequence of touches, the counter will keep adding touches.

5

Please submit a bug repro attached.

6

A bug report has been submitted. The ID is 699675.

7

We are happy to report the touch issue for the desktop in Windows 10 has been fixed.

We tested on Windows 10 Home Insider Preview Build 10163 and the issue doesn’t occur anymore.

8

So it was a Microsoft issue?