# Maxium Touch Index Exceeded, 10, the maxium index allowed is 9

**URL:** <https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109>\
**Category:** Platform & Builds\
**Tags:** Linux, unreal-engine, touch, UE4, question\
**Created:** [June 4, 2019, 8:32am UTC](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109 "2019-06-04T08:32:40Z")\
**Posts on this page:** 20\
**Page:** 1

<div class="post-metadata">

**Author:** ![anonymous\_user\_5c17932a](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_5c17932a](https://forums.unrealengine.com/u/anonymous_user_5c17932a)\
**Post date:** [June 4, 2019, 8:32am UTC](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109/1 "2019-06-04T08:32:40Z")

</div>

Hi, all  
I’m using touch to implement some feature in my project. However, I found touch under linux doesn’t work. The log is as bellows:  
**LogSlate: Warning: Maxium Touch Index Exceeded, 10, the maxium index allowed is 9**

```
Actually, when the program start up, I did the follewing tests:    
First touch:I can touch on the screen and move
Second touch: the fingerleave screen and touch again, touch doesn't work
Thrid touch: work
Fourth: doesn't work
...
Ninetheen touch: 
**LogSlate: Warning: Maxium Touch Index Exceeded, 10, the maxium index allowed is 9**
And the touch didn't work anymore unless I restart the program.

```

BTW, the program can work perfect on windows. Any help? Thank you very much.

---

<div class="post-metadata">

**Author:** ![RCL](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@RCL](https://forums.unrealengine.com/u/RCL)\
**Post date:** [June 4, 2019, 2:21pm UTC](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109/2 "2019-06-04T14:21:43Z")

</div>

Could you please confirm that you’re on 4.21.2 and not earlier (there were changes for 4.21.2 fixing some touch issues). Particularly could you please check that you have [this commit](https://github.com/EpicGames/UnrealEngine/commit/c74660dae29a11ea344fe4cf9ead8768f95e8efa) in your code base.

---

<div class="post-metadata">

**Author:** ![anonymous\_user\_5c17932a](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_5c17932a](https://forums.unrealengine.com/u/anonymous_user_5c17932a)\
**Post date:** [June 6, 2019, 5:28am UTC](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109/3 "2019-06-06T05:28:49Z")

</div>

@RCL Hi ,sorry for late response.  
I’ve checked the version I used both on linux and windows(cross compile binary for linux).  
On Windows, my version is 4.21.2  
On Linux, the patch is in the repo, and I checked the path code manually in my local, it is already here.  
Do you have any suggestions? Because I think it’s important feature for linux developers.

Thanks

---

<div class="post-metadata">

**Author:** ![anonymous\_user\_5c17932a](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_5c17932a](https://forums.unrealengine.com/u/anonymous_user_5c17932a)\
**Post date:** [June 6, 2019, 5:29am UTC](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109/4 "2019-06-06T05:29:27Z")

</div>

@RCL Hi ,sorry for late response.  
I’ve checked the versio I used both on linux and windows(cross compile binux for linux).  
On Windows, my version is 4.21.2  
On Linux, the patch is in the repo, and I checked the path code manually in my local, it is already here.  
Do you have any suggestions? Because I think it’s important feature for linux developers.

Thanks

---

<div class="post-metadata">

**Author:** ![anonymous\_user\_5c17932a](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_5c17932a](https://forums.unrealengine.com/u/anonymous_user_5c17932a)\
**Post date:** [June 10, 2019, 7:06am UTC](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109/5 "2019-06-10T07:06:07Z")

</div>

@RCL any updates? thanks

---

<div class="post-metadata">

**Author:** ![RCL](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@RCL](https://forums.unrealengine.com/u/RCL)\
**Post date:** [June 10, 2019, 6:12pm UTC](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109/6 "2019-06-10T18:12:30Z")

</div>

Try increasing the verbosity for LogLinuxWindows events. Previously, the touch indices were ever increasing because there was a bug in not handling FINGERUP event. The code that you’re referring to should be handling FINGERUP so the first thing to clarify is how the indices get incremented.

---

<div class="post-metadata">

**Author:** ![anonymous\_user\_491cd138](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_491cd138](https://forums.unrealengine.com/u/anonymous_user_491cd138)\
**Post date:** [August 28, 2020, 8:24am UTC](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109/7 "2020-08-28T08:24:30Z")

</div>

In Ue 4.25.1 and Ubuntu 16.04 and 18.04 Linux, SDL\_FINGERUP events are not firing only when doing a swipe. When I tap, the SDL\_FINGERUP event trigger, but when the user swipes, the the SDL\_FINGERUP event does not trigger, and the finger index increments.  
When it reaches 10 the message above occurs.

On Ubuntu 18.04 LTS, after the first missing SDL\_FINGERUP, I start receiving “Received unknown SDL event type=2050” messages which are SDL\_MULTIGESTURE.  
After adding logging to the SDL\_MULTIGESTURE event, you can see that the mgesture.numFingers continues to increment until the application is restarted. I’ve seen numFingers report as high as 80 or 90 fingers on the screen.

After 10 swipes, input stops propagating to the game, and the app needs to be restarted.  
This block can be worked around by clearing the Touches map while processing the SDL\_FINGERDOWN event.  
Touches.Empty();

But, the issue persists. The real issue is that there should be a matching SDL\_FINGERUP event for every SDL\_FINGERDOWN event. and when swiping the screen with a single finger, there should not be SDL\_MULTIGESTURE events firing.

Also, for some reason the logs show that for every other swipe, the logs show input as MOUSE\_UP, then MOUSE\_DOWN, and the other swipes coming in as SDL\_FINGERDOWN, followed by SDL\_FINGERMOTION without an SDL\_FINGERUP.

There is custom logic in the libSDL2 included in UE’s source, so I believe the bug may originate there.

This is the only showstopper in our upgrade from 4.14 to 4.25. It would be great if this can be addressed quickly.

These are the changes I made to LinuxApplication.cpp and SlateUser,cpp to get more consistent logging, and prevent input from being blocked after 10 swipes. Our game does need that SDL\_FINGERUP event though.

And adding this to DefaultEngine.ini (on the game side) will filter out log entries unrelated to Touch, and show verbose logging for log messages related to Touch.

```
[Core.Log]
global=Error
LogLinuxWindow=Verbose
LogLinuxWindowType=Verbose
LogLinuxWindowEvent=Verbose
LogSlate=Verbose
LogLinux=Verbose
PixelStreamerInputDevice

```

link text

---

<div class="post-metadata">

**Author:** ![And215](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@And215](https://forums.unrealengine.com/u/And215)\
**Post date:** [November 10, 2021, 2:32pm UTC](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109/8 "2021-11-10T14:32:33Z")

</div>

We are running into this exact issue with UE4.27.1 and Ubuntu 20.04.3 LTS. This is a huge problem. Is there a fix available? Why is Unreal using a custom SDL library?

---

<div class="post-metadata">

**Author:** ![anonymous\_user\_09d6133d](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_09d6133d](https://forums.unrealengine.com/u/anonymous_user_09d6133d)\
**Post date:** [October 5, 2022, 3:07pm UTC](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109/9 "2022-10-05T15:07:58Z")

</div>

I am also seeing the same problem on UE5.0.3+Ubuntu20.04. I can’t imagine why Unreal hasn’t fixed such a critical bug.

---

<div class="post-metadata">

**Author:** ![onionsssss](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@onionsssss](https://forums.unrealengine.com/u/onionsssss)\
**Post date:** [April 19, 2023, 7:15am UTC](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109/10 "2023-04-19T07:15:49Z")

</div>

Excuse me！Have you resolved it？

---

<div class="post-metadata">

**Author:** ![onionsssss](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@onionsssss](https://forums.unrealengine.com/u/onionsssss)\
**Post date:** [April 19, 2023, 7:15am UTC](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109/11 "2023-04-19T07:15:52Z")

</div>

hi！I would appreciate it if you can help me to analyze your code.

---

<div class="post-metadata">

**Author:** ![mlancelot-hrv](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@mlancelot-hrv](https://forums.unrealengine.com/u/mlancelot-hrv)\
**Post date:** [July 18, 2023, 10:46am UTC](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109/12 "2023-07-18T10:46:29Z")

</div>

Same issue here with UE5.2.1, can somebody at Epic help with this ? This is a huge issue at the moment in my company, we cannot ship Linux builds with Touch…

---

<div class="post-metadata">

**Author:** ![mlancelot-hrv](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@mlancelot-hrv](https://forums.unrealengine.com/u/mlancelot-hrv)\
**Post date:** [September 21, 2023, 12:57pm UTC](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109/13 "2023-09-21T12:57:33Z")

</div>

Ok, if anyone’s wondering how to solve it I tested a lot of thing and figured out that setting the Input Mode To Game Only seems to solve the problem, just add the node “Input Mode Game Only” to your Game Instance or Gamemode at startup and I don’t have the problem anymore…

---

<div class="post-metadata">

**Author:** ![TFA\_aaronfhd](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@TFA\_aaronfhd](https://forums.unrealengine.com/u/TFA_aaronfhd)\
**Post date:** [October 26, 2024, 12:26pm UTC](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109/14 "2024-10-26T12:26:57Z")

</div>

I am having this issue on CENTOS 7 and CENTOS 9

LogSlate: Warning: Maximum Touch Index Exceeded, 10, the maximum index allowed is 9

Out touchscreen that we where testing changed models. The touchscreen used to send BTN\_LEFT

this was handled fine. Now the new one sends BTN\_TOUCH.

when this is fired 10 times Unreal becomes unresponsive to touches.

I have tried multiple blueprints to see how I can ignore any “Pointer Indexes” about 9

but even though that is there unreal still becomes unresponsive to touches.

Any help as we will be in the future using this Touchscreen

---

<div class="post-metadata">

**Author:** ![TFA\_aaronfhd](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@TFA\_aaronfhd](https://forums.unrealengine.com/u/TFA_aaronfhd)\
**Post date:** [October 27, 2024, 5:17pm UTC](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109/15 "2024-10-27T17:17:19Z")

</div>

Anyone???

---

<div class="post-metadata">

**Author:** ![TFA\_aaronfhd](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@TFA\_aaronfhd](https://forums.unrealengine.com/u/TFA_aaronfhd)\
**Post date:** [October 28, 2024, 6:44pm UTC](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109/16 "2024-10-28T18:44:30Z")

</div>

Ok it seems the issue is that I get a touchStarted event,

but I also get a mouse event. which prevents the touchEnded to happen.

---

<div class="post-metadata">

**Author:** ![aaron.fritz](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@aaron.fritz](https://forums.unrealengine.com/u/aaron.fritz)\
**Post date:** [October 30, 2024, 3:25pm UTC](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109/17 "2024-10-30T15:25:19Z")

</div>

Also seems to be a linux issue as Unreal engine seems to not release the Touch Event as the OS moves the mouse and the touch at the same time

Any fixes or a way to handle this???

Any Developers on here

---

<div class="post-metadata">

**Author:** ![TFA\_aaronfhd](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@TFA\_aaronfhd](https://forums.unrealengine.com/u/TFA_aaronfhd)\
**Post date:** [November 3, 2024, 10:33pm UTC](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109/18 "2024-11-03T22:33:12Z")

</div>

Still having this issue, would like to see how it can be resolved. As it is related to linux.

---

<div class="post-metadata">

**Author:** ![aaron.fritz](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@aaron.fritz](https://forums.unrealengine.com/u/aaron.fritz)\
**Post date:** [November 5, 2024, 4:20pm UTC](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109/19 "2024-11-05T16:20:43Z")

</div>

Still having this issue in linux.

---

<div class="post-metadata">

**Author:** ![aaron.fritz](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@aaron.fritz](https://forums.unrealengine.com/u/aaron.fritz)\
**Post date:** [November 5, 2024, 4:22pm UTC](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109/20 "2024-11-05T16:22:10Z")

</div>

Did you ever figure this out?

[Next page](https://forums.unrealengine.com/t/maxium-touch-index-exceeded-10-the-maxium-index-allowed-is-9/450109.md?page=2)