Question by cheesemaster · May 23, 2021 at 02:56 PM · fps profiler legacy

When upgrading Unity 2017 to Unity 2021 framerate drops by 50%

Hi, I had recently (using the Unity Javascript to C# converter) managed with quite a bit of work to upgrade Unity from 2017 to Unity 2021. After fixing thousands of compiler/runtime errors and beginning to test it I noticed the framerate had dropped from about 60fps to 30fps on the Android devices we were deploying to.

To investigate I had a look at the Profiler and found there was a huge amount additional work going on in 2021 for the previously trivial processes of drawing rectangles etc using the legacy GUI system, with GUI.Repaint() doing about 5x more work.

Attached is a typical slice from within the Profiler in 2017: alt text