Re: Obj-C cross platform compilation

[Philippe C.D. Robert]

On Thu, 10 Apr 2003, Salter, Adam Q wrote:
> I received no reply to my last email (maybe my email is not working
> correctly - is this the correct list?). Thanks in advance,

It is working, but I guess the questions are a little too unspecific :-)

> Dear all,
>
> I am investigating writing a cross platform application (game)... I
> really like the Obj-C syntax and object model. My question is this: what
> do I need to do this?
>
> - can I use GNUStep?

Depends on what you want to do. If you plan to use the FoundationKit together
with eg. SDL and OpenGL, then yes. If you plan to use the AppKit as well,
then you should be aware that it is not working/stable eg. on Windows. If you
plan to write a 'simpler' game (UI wise) then you might want to look at some
of the existing ones, eg. Gomoku.

> - do I really need to subclass NSObject (makes life a lot simpler I
> imagine with custom allocation/deallocation) for my own objects?

You don't (if you do not want to use GNUstep) but it makes life much easier :-)

> - would the binary run slower than straight C++?

Again, it depends on what you do. The main issue for performance decreases
compared to a C++ appl (wrt to C++ vs ObjC) is probably message passing,
but the effect of this can be minimised by using IMPs (RTFM :), plain C
functions where needed and most important by a good design. Also note that
we are not talking about magnitutes here :-)

> - does it require an extra library/run-time environment? (on
> Linux/Windows where it is not installed by default)

You have to install GNUstep, of course. For Windows there is an experimental
installer available since recently (see http://www.gnustep.org/newindex.html
or the recent emails about this topic).

> SDL/OpenGL are easily cross platform and with those and a nice
> View/Controller/Data model I should be cooking quite quickly - if it is
> really possible.

It is.

HTH,

-Phil
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