Framerate lags create physics simulation problems on Android

[4.8.3. binary. blueprint only project]
This issue may be related to this one: [Gravity for an actor changes randomly after open level on Android][1]

Sometimes frame rate lags on a few different devices tested, and when that occurs coinciding frequently with a collision, the hit produce an overpowered impulse, the object get very high speed acting not as expected for my gameplay.

This are exact words from one of the users of my game:
“… when lag occurs during a collision, the large delta time is multiplied by the velocities causing them to overlap a fair amount, and ultimately causing the ball to go flying much further than intended.”

I have tried many thigs and reduced some lag concurrency… for example I have disabled level and texture streaming, I don’t want that my app access disk when the simulation start, but anyway seem it does some blocking task… one of them when activating the AdMob, the game lags when the Ad appears for first time.

This is the link to the game on play: https://play…com/store/apps/details?id=com.denysalmaral.CrabbyBall

Kind regards

Gravity for an actor changes randomly after open level on Android - World Creation - Epic Developer Community Forums

Hey piX,

Do you know which devices are having collision troubles with your game ‘Crabby Ball’? I’ve downloaded your game from a couple of phones here, a Samsung Galaxy s5 and a Motorola Droid Turbo. I did not experience any collision lag on any of the devices.

Looking forward to hearing back from you, please provide some additional information. :slight_smile:

Hi ,
The issue appears more frequently on older/slower phones. Even is hard for me to reproduce it on my Galaxy S4 mini. The problem used to rise on a Samsung S2 and a old Galaxy TAB. I don’t have them at hand but i’ll try to record a video when I have the opportunity so I can show it to you.
I know UE4 will need some minimum requirements, but if my game is running well and smooth on those old phones, will be sad that a simple collision issue could ruin opportunity to behave well on those devices.

The who I quoted having this issue is using a: [Samsung galaxy avant on android 4.4.2][1]

Samsung Galaxy Avant - Full phone specifications

Hey piX,

I’ve spoken with some developers and it has been suggested that in physics project settings, you can control the delta time which may help the situation that your customers are seeing. As of 4.9, we are also supporting sub-stepping on mobile devices.

Hi ,
No I release that I was wrong thinking all time that my game was using sub-stepping since I have that checkbox checked :slight_smile: then it currently works only on the editor and PC. I’ll play then with that delta time… and wait for the next update to 4.9
Thanks a lot for your help and the good news,
best regards,
piX