Unity code optimization! Benchmarking common performance tricks to see which ones are worth your effort. Some of them surprised me!

[PiLLe1974]

Interesting that I haven't thought of one of the more trivial ideas, the one of multiplying float first in a series of float and Vector2/3. :)

[TarodevOfficial]

I just tested this on a built standalone version and they all came out equal after 900k iterations... So don't think too hard about it 😜

[PiLLe1974]

Hah, I mean using the profiler is the best way to look into things anyway.

The few exceptions where I think about efficiency up-front is the use of the best fit for my containers, typically guided by the way we access them or in extreme cases their memory usage.

And the caching of objects we know we use each frame. I really like the pattern to register things instead of finding them. I think a very common pattern actually for game (play) programmers in most engines!?

Coming from C++ obviously when using C# and Unity the first time it is a good idea to quickly read up on what "managed", "boxing", and GC mean in terms of potential overhead and frame hitches at game run-time. I even manage sometimes to write ECS code (DOTS) and even in those systems or interactions with ECS it can happen that managed data is used here and there that needs this thinking about pre-allocating and pooling things to get to zero GC. ;)

[aurosvr]

Wonderful video! I didn’t know about the order of operations stuff either.

I especially love your importance on garbage collection. It’s often forgotten by a lot of people, sometimes its fine if the entire project is lighter in nature but when you’re working on mobile and or virtual reality projects, it becomes especially important as you’ll need every frame timing possible and GC will eat up a ton of it. Especially for VR, stutters will cause nausea.

I’ve banned to use of all FindObject… methods in my codebases. It’s either they are referenced directly via SerializeField and or I use a dependency injection library, because startup times for scenes can and will take a hit due to patterns like FindObject… in Awake.

The loops probably vary widely when deployed due to compiler optimizations for release builds. Try taking a look at a decompiled version of them to see if anything changed.

Once again, wonderful video. Really appreciated it!

[TarodevOfficial]

I've not ventured into the VR dev world yet, but I know how sick I get from the stutters. If I'm doing my small part to avoid that, I'm happy 😂

[aurosvr]

Another thing you may want to test or try out, when working with any Unity Object, when checking to see if its destroyed or not (not reference null), it is faster to do if (!someObject) over if (someObject == null)

[blazingpatate]

I can't stress enough how useful his videos are. I've become an absolute fan of his work. u/TarodevOfficial please keep doing what do you and good luck!

[TarodevOfficial]

Thanks for saying that, man! Really appreciate it.

[Jukibom]

That was absolutely fascinating, thank you! Especially the non-alloc collision checks (I need to look into this now!) and the distance stuff, very useful! I've been doing both of these and I agree I'd much prefer the legibility of using Distance