how are arrays stored in memory in the iOs Player

Questions & Answers
1

I am developing an iOs project which needs to store a lot of optimised level data.

Because I am developing for iOS I want the smallest memory foot print possible.

The data is a large number (tens of thousands) of simple structures e,g,

‘MyVector’ is a class with 3 int members x,y, and z

MyVector3 a10000Vectors = new MyVector3[10000];

Does anyone know how an array of this kind would be stored in memory?

Is there a single block of memory with 30000 closely packed ints
or is it this plus another array of 10,000 pointers into 10,000 addresses in this block
or is it a list of 10,000 pointers and 10,000 separately allocated tiny blocks of memory
or something else?

Also does it make a difference if these are structs or classes? Do structs and classes have the same distinction in Unity that they do under .Net/Mono. Are structs values and classes reference values?

Is it smaller to have 3 separate arrays of int one for each components of the vectors?

Thanks in advance for any help.

2

Unity uses Mono, so anything that applies to Mono applies to Unity. A Vector3 is 3 floats, so one Vector3 uses 12 bytes. There are no ints involved (although ints and floats both use 4 bytes.) Making 3 arrays of floats vs. 1 array of Vector3 makes no difference as far as memory goes; you are using the same amount of data both ways.