VectorTest.cs

using UnityEngine;
using UnityEngine.Profiling;
using System.Runtime.CompilerServices;
using System.Collections.Generic;

public class VectorTest : MonoBehaviour
{
    Vector3[] array;
    List<Vector3> list;

    // Start is called before the first frame update
    void Start()
    {
        array = new Vector3[313370];
        list = new List<Vector3>(array.Length);
        for (int i = 0; i < array.Length; i++)
        {
            array[i] = new Vector3(Random.value, Random.value, Random.value);
            list.Add(new Vector3(Random.value, Random.value, Random.value));
        }
    }

    static Vector3 FastScalarMul(Vector3 v, float f)
    {
        Vector3 result;
        result.x = v.x * f;
        result.y = v.y * f;
        result.z = v.z * f;
        return result;
    }

    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    static Vector3 FastInlinedScalarMul(Vector3 v, float f)
    {
        Vector3 result;
        result.x = v.x * f;
        result.y = v.y * f;
        result.z = v.z * f;
        return result;
    }

    // Update is called once per frame
    void Update()
    {
        Profiler.BeginSample("Unity");
        for (int i = 0; i < array.Length; i++)
            array[i] *= 42f;
        Profiler.EndSample();

        Profiler.BeginSample("Fast");
        for (int i = 0; i < array.Length; i++)
            array[i] = FastScalarMul(array[i], 42f);
        Profiler.EndSample();

        Profiler.BeginSample("Inlined");
        for (int i = 0; i < array.Length; i++)
            array[i] = FastInlinedScalarMul(array[i], 42f);
        Profiler.EndSample();

        Profiler.BeginSample("Direct");
        for (int i = 0; i < array.Length; i++)
        {
            array[i].x *= 42f;
            array[i].y *= 42f;
            array[i].z *= 42f;
        }
        Profiler.EndSample();


        Profiler.BeginSample("ListUnity");
        for (int i = 0; i < list.Count; i++)
            list[i] *= 42f;
        Profiler.EndSample();

        Profiler.BeginSample("ListFast");
        for (int i = 0; i < list.Count; i++)
            list[i] = FastScalarMul(list[i], 42f);
        Profiler.EndSample();

        Profiler.BeginSample("ListInlined");
        for (int i = 0; i < list.Count; i++)
            list[i] = FastInlinedScalarMul(list[i], 42f);
        Profiler.EndSample();

        Profiler.BeginSample("ListDirect");
        for (int i = 0; i < list.Count; i++)
        {
            Vector3 v = list[i];
            v.x *= 42f;
            v.y *= 42f;
            v.z *= 42f;
            list[i] = v;
        }
        Profiler.EndSample();
    }
}