UnityGame/Library/PackageCache/com.unity.mathematics/Documentation~/compatibility.md

Compatibility with UnityEngine mathematics

If you want to Burst-compile your project, it's best practice to use the Unity Mathematics package by default and only use Mathf when necessary. Unity Mathematics isn't implemented in the same way as the UnityEngine.Mathf struct in the core Unity engine. Because of this, if your application relies on the specific behaviors of Mathf, you'll have to reimplement them to get similar behavior in Unity Mathematics.

Important

For performance reasons, if your project uses the Mono compiler, you should continue to use the mathematical operations in Mathf, rather than Unity Mathematics.

You can use both Mathf and Unity Mathematics methods in your project, but it might impact on the performance of your application because the conversions between the UnityEngine and Unity.Mathematics types such as Vector3 to float3 and vice-versa are performance-intensive.

Porting UnityEngine code to Unity.Mathematics

If you want to migrate code from UnityEngine to Unity.Mathematics, you need to make the following changes first:

• Update UnityEngine types to Unity.Mathematics types. For example, Vector4 to float4, and Quaternion to quaternion. These examples aren't exhaustive: see the Scripting API reference for the full list of Unity Mathematics types available.
• Update any operators involved in matrices or vectors. For example, the Matrix4x4 multiplication operator implements matrix multiplication, but the float4x4 multiplication operator implements componentwise multiplication.
• Degrees to radians
• How your code generates random numbers. Random in Unity.Mathematics works differently to Random in UnityEngine. You can completely control random number generation with Random in Unity.Mathematics, and it's instanced, rather than static. It's also exclusive with its upper bound, which is important to bear in mind if you want to convert UnityEngine code which is sensitive to the bounds. For more information, see the documentation on Random numbers.