Mobile: Touch failing over 50% CPU usage.

*** EDIT: Updated original post with recent findings ***

Currently I'm doing a lot of testing for my game on several devices. Ranging from upper low end phones, to high end phones. I've noticed that on some phones, especially windows phones touch will fail and cause a massive lag in the touch.

On my Main testing device - 2 year old - mid range - Nokia Lumia 830, when the test runs at just about 40-55 CPU usage, and as soon as it goes above that magic 50% I'm noticing lag or failure in the touch input.

Have anyone noticed anything similar when testing their game on low-mid range phones?

I made this test to try it and confirm touch is failing as CPU get's higer.

http://www.tunepunk.com/touchtest

If you notice any touch lag please report in this thread.

Phone model.

CPU - Min, Max, Average

FPS - Min, Max, Average

UPDATE: Touch is very slow, not responding well in some cases, but in game when I lock the screen and unlock again with the touch starts to respond again. (Mortar Melons, Last of the Survivors, Made with C2, windows on phone store, has the same issue)

So far it seems to be a Windows Phone issue, but curious if any other devices has the same issue.

Any help appreciated.

This is really weird because firstly there is no technical reason CPU usage should affect touch input at all, secondly there really ought to be nothing special at all about the 50% mark, and thirdly because C2's measurement of CPU is a *very* approximate estimate based on timers instead of any real CPU measurement so is probably only accurate to +/-10% at best. So it's unlikely to actually be at 50% when it says it is. I would think it's likely something else is the cause and you've falsely correlated it with CPU.

Ashley I created this test scene.

Capx:

https://dl.dropboxusercontent.com/u/20560446/Scirra/touchfail.capx

Test directly.

http://www.tunepunk.com/touchtest

press + to add more dots.

press - to remove dots.

hold to move blue dot.

as you can see FPS is still decent, but touch is failing above 50% cpu.

I just tried this scene on a LG Nexus 5X, stock android. The Touch never failed even as I was approaching 80% CPU.

The 50% mark is not an issue here. But on Windows Phone it is, even if I build an app with Visual Studio and XDK

I havn't tried this test on any Apple device yet. But the same seemed to happen on Samsung galaxy S3 as well.

I just also tried the touch test in another browser (UC Browser) on same windows phone device (Nokia Lumia 830). Touch doesn't fail, but as soon as I'm touching the screen the FPS drops about 20%.

I don't know if this is a windows phone issue, or I'm just having a faulty device, but it seemed to happen on the Samsung Galaxy S3 as well.

Ashley do you have any windows phone to test this one?

http://www.tunepunk.com/touchtest

I just need to confirm if my device is faulty or it's a problem across all Windows phones. If the problem is a windows phone issue, i can contact them about it. And if it's a pure windows phone problem I need to put the windows phone version on hold and focus on Android/iphone until it's fixed.

Ashley It seems like on startup touch seems to fail to initialize correctly or something, or maybe stuck in some loop?

I just noticed that the Touch Lag/unresponsiveness goes away if i lock the screen in game, and then unlock it again on Windows Phone.

This also helped on other C2 games for windows phone like (Mortar Melon and Last of the Surviors)

I still need to confirm if All windows phones have this problem or if it's just my device. So calling out for anyone with a windows phone.

Confirmed. Bizarre. Lumia 550. When first started, after 6 clicks on +, I can move in circles, lift my finger, and watch the dot follow my path in slow motion. Press the power button, press again to get back to the app, and responsiveness is immediate, even hitting + X times.

Confirmed. Bizarre. Lumia 550. When first started, after 6 clicks on +, I can move in circles, lift my finger, and watch the dot follow my path in slow motion. Press the power button, press again to get back to the app, and responsiveness is immediate, even hitting + X times.

Ahhhh. Thank you! I thought I was going crazy! I've spent countless hours/weeks optimizing the game to keep as low CPU level as possible to reduce the lag. And woooops..., close screen open, and the lag is gone. I don't think It's a Construct 2 issue though. I did the same test on some of the Intel XDK demos that comes with the app preview. (I doubt they are done in C2 but don't know for sure) and notice the same behaviour. This seems to be a Microsoft issue from what I'm guessing but so far I can't confirm

So Lumia 830 and Lumia 550 is confirmed to have this issue.

I hope more people can do the test as I had a report that som older Android devices had a similar issue, but i havn't tried myself.

**Edit: Another funny thing is that this behaviour is apparent even if you build with XDK or even Visual Studio.

I accessed the touchtest link you provided on two devices. An iPhone 5 and a Samsung Galaxy SII.

on the iPhone 5 the CPU usage seemed to max out at about 75% (wouldn't go higher). But even at that CPU usage the touch didn't lag or slow down at all. Touch was still responsive. The blue dot moved around on the screen with no lag.

The Samsung crapped itself though. At CPU usage of 85% the touch controls became so laggy as to be unusable.

Not sure if that info is useful to you.

Artpunk thanks for the info. It seems like it's a Windows Phone bug. As blackhornet also reported touch becomes unresponsive at around 50% ,but if you lock the screen - unlock and it's back to normal. Very weird. I've sent a bug report to MS, so hope they will fix it. It's the same behaviour on other C2 made games in the windows store as well.

I mentioned this before, I too have faults in touch with my game, so far I could not prove it but it seems that there is something wrong with the system touch.

Galaxy s6 with android 6.

— Did you try this test? does it fail as well?

http://www.tunepunk.com/touchtest

Artpunk thanks for the info. It seems like it's a Windows Phone bug. As blackhornet also reported touch becomes unresponsive at around 50% ,but if you lock the screen - unlock and it's back to normal. Very weird. I've sent a bug report to MS, so hope they will fix it. It's the same behaviour on other C2 made games in the windows store as well.

Very weird. I use touch in my game, and I haven't noticed any problems on low end Android phones (ie, Samsung Galaxy SII). But I haven't tested on Win Phone, I need to do that asap.

When you say other C2 games have the same problem on Win Phones, how do you know that? From your own testing? Or others have reported it elsewhere?

Artpunk I downloaded "Last of the survivors" "Mortar Melons" from the windows store on my phone. They have the same issue. But if I lock and unlock the screen they work well.

— Did you try this test? does it fail as well?

http://www.tunepunk.com/touchtest

I tried that test but I found a little confusing, why not add a indicator or something that highlight the detection of a touch ?.

Or maybe you see something on the screen to indicate that the touch has been detected.

You could also add a text str (sprite.count), so you can see when the touch has been detected since this variable will increase its value.