I have a few questions about how memory allocation with C# works... Here is an example:

See this and this for the answer.

You won't need to use the ref keyword because  Ship is defined as a class.  in C#, all classes are Reference types, while all structs are Value types.  Reference types will always be passed by reference, while value types will always be copied by value unless you use the ref keyword :-)

Ah, thanks guys.

To find things to optimize, you should not be reading code, you should be measuring your code. Use a System.Diagnostics.Stopwatch, or PIX for Windows, or similar tools, to figure out what (if anything) you need to optimize.
If you optimize something so that it takes no time at all, but it only took 0.5% of the overall time before, then you have only improved your frame rate by 0.5%... Not the right thing to optimize.

The problem is it runs great on my PC, i can have over 1000 objects with no real issues.

Then it could be the GPU is being used inefficiently (since those are very hard to diagnose). Have you gone through these blog posts (under Performance and GPU Performance)? They were extremely helpful when I had performance problems with my game.

this is a great article on this topic :-)

This post is quite intresting as im currently in the proccess of designing my game layer methods (sorry about thread hijacking).

Does my logic below sound correct?

My logic is to create X number of objects that are used over and over.

e.g.

List of Object

ID = 1 Blue Box
ID 2 = Tree
ID 3 Red Box

Map matrix (int[,] map [X,Y])

1,1,2,3,1,1
1,1,2,1,1,1
1,1,2,3,1,1

I initilise each object with there given texture and attributes.

When drawing I just cycle through the map matrix and draw the relivent object in to correct co-ordinates.

That way there is only a limited number of objects in the memory rather than loads 100's

One part I am confused by is if I had an interactable object (treasure chest etc), I would need to "clone" the object so that each object could be opened and contain a different item?

Is there any advantage to cloning then creating a new object, other than have to set the inital settings?

When you start cloning you need to be aware of the difference between deep and shallow copies.  In your treasure chest example I would probably go with just creating a new treasure chest object each time (or if there are very many and they are short lived consider using a pool).  That way you know exactly where you are, and you won't accidentally end up with treasure chests sharing some sub-object that you didn't intend.

Beringela:

In your treasure chest example I would probably go with just creating a new treasure chest object each time

Agreed. Even if there's a lot of them it's the right way to do things.

DeadShawn:

Ah, thanks guys.

I thought I had found something I could optimize, but I guess not!

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