Evaluate performance of PressableButtonUnityUI

[ritijain]

Describe the Issue

Creating 3D content using UnityUI can be fairly tricky, and can cause performance issues. There have been some concerns raised by partners that when a button which is a very core components of any app is not performant, it can cause some serious perf issues.

I realized that the Unity UI pressable button is using 2 Image components rendered at different Z depths. While it looks great and is fully functional, how does it impact perf?

[ritijain]

@AdamMitchell-ms , @julenka -

I am not sure if a discussion about performance happened when this work was done. If this seems like a legit concern, then there should be a perf evaluation of this (and similar unity ui) components.

If there are no concerns, i think it would be great to capture the discussion on Github so that we can point it to folks who express concerns.

[Zee2]

This is an ongoing concern for Canvas-based elements in MRTK3. Already having an ongoing discussion with @Cameron-Micka for how best to mitigate drawcalls here.

[Zee2]

Investigation is ongoing and promising developments are in order :)

[AMollis]

@marlenaklein-msft Can you follow-up with @Cameron-Micka on his ideas here

[AMollis]

We're now tracking this issue with the following investigation task

• Investigate performance improvements to canvas UI#11471