On Saturday, May 7, 2016 at 2:59:08 AM UTC-4, Ford Ox wrote:
>
> I want to do small simulation (similiar to games) where I have multiple
> objects that can move and spawn at map. What is the most efficient way to
> do that?
>
It depends on how many objects you have and the size of your grid. If you
don't have much experience with this type of problem, I would strongly
recommend taking whichever approach is easiest, then profiling to find the
bottlenecks.
>
> I was thinking about something like this:
>
> @doc "I wont to be able to check for collision in constant time"
> map = Array{Union{all objects...}(1000000, 100000)
>
>
>
This creates a 100GB array! If your map is that big, then you need another
approach (storing your objects in a vector for example)
> Is this the most efficient way?
> Also, why do I have to specify the type of map array (Union..), when I
> will technically store there only pointers, which are all of the same size.
>
Yes, but arrays of chars (for examples) can be much more efficiently
packed, that's why you need to specify a type.
> If I use Array{Any}, will it be as fast as using Union{..} ?
>
My guess is "essentially, yes", but profiling is the only source of truth.
See the Julia performance tips.
>
> Should I make map, moveable_objects_1-5 global variable, so I dont have to
> send it as parameter every time?
>
Globals have very poor performance in Julia at the moment, unless you can
make them const.
> (That will make my code unusable when imported by somebody else right?)
>
It depends. But yes, in general, it's better practice to pass the world
state as an argument than having it as a global.
> Or should I pack them inside one type (f.e. type Data)? I am used to
> [this.](..) so this is kinda new to me.
>
Yes, that's reasonable.
