Everyday Unity

Using DOTS to optimize GameObject gameplay: A case study from Survival Kids | Unite 2025

The recording is available now.

https://www.youtube.com/watch?v=ZkvK0mX-id4

#optimization

Optimizing Burst matrix multiplications

A deep dive into optimizing matrix multiplications. A story of multiple optimization attempts, moving from basic implementation to hand-tuned intrinsics.
Key takeaways from the optimization journey:
* Switching to Unity’s Mathematics package (SIMD-friendly) immediately gave a massive boost over standard C#.
* The Low-Hanging Fruit: Using FloatMode.Fast allows the compiler to merge instructions into Fused Multiply-Add (FMLA).
* Reinterpreting NativeArray<Matrix4x4> as float4x4 helps the compiler see the data layout more clearly, reducing instruction count.
* Utilizing Affine Matrices (since most game objects don't use perspective projection) allows you to skip calculating the 0,0,0,1 row, saving significant cycles.
* Using Intrinsics and float4x3 to pack data tightly into vector registers.
This is a must-read if you are working on high-performance physics, skinning, or animation systems in Unity.

https://medium.com/toca-boca-tech-blog/optimizing-burst-matrix-multiplications-bfb301de80ce

#burst #optimiziation

The Unity Engine Roadmap

It was impossible for me to share live at Unite all the great features they have planned as it was so packed. Check the recording and you'll definitely find something interesting for you.

I posted the most exciting stuff for me live on the 19th of November, what do you expect the most from the roadmap?

https://youtu.be/rEKmARCIkSI

#roadmap

Talk: Understanding Unity Memory

I recommend checking the recording as Richard gives a gentle intro into how memory works. It must be interesting if you haven't learned it before.

There were a few slides that caught my attention:
- how to use unsafe to allocate your data sequentially in memory in his particular case
- other GC in Unity used for assets etc
- when to split big structs

Talk: Keeping it simple and indie on Multiplayer

What a nice day-1 set of features for the speaker and his indie game

It was quick overall. Not as rich in advice as previous years. Especially 2017-2019 talks on the same topic, which are my all time favourites.
Make sure to check them, here is my overview of these talks: https://gamedev.center/best-optimization-tips-by-unity-engineers-at-unite/

Assets loading section

Disable audio preloading
Tune Async Upload Pipeline
Strip shader variants, less shaders to load and compile

The final tip on shaders about how to check what goes into build

Use ifs in shaders instead of keywords. Profile it. It might be better for your case.

Sounds like the exactly same advice from the last year about shader variants and how to optimize it. Nicolas goes into more details how keywords and variants work

The next default tip: disable domain reload on entering play mode

How to speed up the compilation.

I worked at a project with 1800 assemblies. Everything was slow: Unity compilation, domain reload, Rider processing all these solutions. So it's a good advice to keep track of your compilation and assemblies count in control

A default tip from every year about how transform hierarchies work in unity and how it can be parallelized