Multi Position .SetPosition is creating large allocations (Unity SetMultiplePositions call)

Question

Hello,

We've set up the call to AkSoundEngine.SetMultiplePositions and it is working well if we're using the AkPositionArray.Add(AkVector64 pos) every time.
However, clicking through to the source, it seems this is marshalling to a byte[] array when using add, and profiling into the project this is causing a large amount of allocations (in our case per frame). Specifically the BitConverter.GetBytes[] in the Add function (which has comments from the AK team that acknowledge this)
Is there a way around these allocations, indexing into the AkPositionArray directly or anything of the sort that we're missing?

Thanks!
(Wwise 2024.1.6 - Unity 6000.0.27f1)

Answer 1

Yes, I also noticed this causes frequent GC allocations. So I switched to the following `unsafe` code: it reinterprets the `float` bit pattern as an `int` (via pointer cast) and writes it directly, avoiding the `BitConverter.GetBytes` allocation overhead.

// Previous (allocates a new byte[4] each time):
// Marshal.WriteInt32(m_Current,
// BitConverter.ToInt32(BitConverter.GetBytes(in_Forward.x), 0));

// Optimized: reinterpret the float bits as int (no GC)
System.Runtime.InteropServices.Marshal.WriteInt32(m_Current, *(int*)&in_Forward.x);
m_Current = (IntPtr)(m_Current.ToInt64() + sizeof(float));