Problem Description
CPU use is very high on iOS using asm.js engine even though project has no active events.
Attach a Capx
http://www.zoytek.co.uk/bugs/physics/Physics-CPU-High.capx
Description of Capx
The capx displays 2 immovable squares with the physics property. Both squares are rotated 90 degrees. The CPU use in the IPA is a high 90%
When the left square is NOT rotated, the CPU use is a modest 8%
Browser preview performance is fine, the high CPU use only appears when both squares are rotated 90 degees. Very odd behaviour!
Steps to Reproduce Bug
- Export the capx to Cordova, iOS8, unminified
- Build adhoc in the Intel XDK, download and install the IPA.
- Install and run to observe high CPU use. (My test device is iPod 5th Gen, iOS 8.2)
- Modify the capx to set the rotation of the left square to 0.
- Re-export, complie, and install and observe low CPU usage (hopefully you will also see what I am seeing)
Export settings:
Screenshot of high CPU use:
Screenshot of low CPU use:
Observed Result
CPU use is high with 2 squares rotated 90 degrees. CPU is OK with just one square not rotated!
I've been benchmarking physics performance and I've narrowed it down to this rotation. The strange thing is I've re-done the capx from scratch and the performance has been fine. So I am confused as to why this is the case. I hope the attached capx has captures the problem.
Box2D web is fine in both cases. Hopefully this is reproducible so you can see the unusual high CPU use with asm.js in this particular scenario.
Expected Result
The same CPU use for both scenarios. Both should be low single digits as nothing is happening in the event sheet, apart from the text box update every 0.05s
Affected Browsers
iOS problem - Cordova iOS8 App, buil with Intel XDK.
Operating System and Service Pack
Win 8.1 64 bit
Construct 2 Version ID
r200