[racket] Figured out the Mac OS X crashing issue for liballegro / libsdl / etc...

Ok it seems `initialize-ns-app' might not be necessary after all, sorry. I looked at the python allegro5 bindings and they run a users thunk by passing it to al_run_main which does all the proper initialization.

;; allegro5.rkt
(define (run thunk)
  (define (callback argc argv)
    (thunk)
    0)
  (run-main 0 #f callback))

;; user code
(define (my-game)
  (define display (create-display))
  ...)

(allegro-run my-game)

On 01/13/2013 03:35 PM, Jon Rafkind wrote:
> Does the entire application have to live within the dynamic extent of the `initialize-ns-app' call or just making the screen?
>
> (initialize-ns-app (lambda () (create-display))
> (do-rest-of-program)
>
> or
>
> (initialize-ns-app (lambda () (create-display) (do-rest-of-program))
>
> On 01/13/2013 03:14 PM, Danny Yoo wrote:
>> Hi Jon,
>>
>>
>> [Also CCing the Racket mailing list.  For folks who are writing
>> bindings to graphical libraries such as SDL, the following should be
>> relevant.]
>>
>>
>> When using the Allegro bindings on Mac OS X, the user will see an
>> exception on screen instantiation unless the program's running under a
>> Cocoa context.
>>
>> Folks from other communities have figured out how to solve this.  In
>> particular, the PySDL folks have a small module to set it up.
>> (https://github.com/albertz/PySDL/blob/master/SDL/__init__.py)
>>
>> I've ported the heart of this to Racket:
>>
>>     https://gist.github.com/4526379
>>
>> (Comment the use of initialize-ns-app in that code; I added it to make
>> sure it was getting called.)
>>
>>
>> initialize-ns-app provides a Cocoa context in which all the rest of
>> the graphical library usage must occur on Mac OS X.  So, typically
>> code will look like:
>>
>>    ;; load foreign libraries...
>>
>>    (initiaize-ns-app
>>       (lambda ()
>>          ;; Now it's safe to create the screen in here ...
>>       ))
>>
>>
>>
>>
>> If you don't do something like this, you'll see this exception as soon
>> as you start initializing the screen:
>>
>> 2013-01-13 15:07:22.716 racket[26263:707] *** Terminating app due to
>> uncaught exception 'NSInternalInconsistencyException', reason: 'Error
>> (1000) creating CGSWindow on line 259'
>> *** First throw call stack:
>> (
>> 	0   CoreFoundation                      0x00007fff8e6ca0a6
>> __exceptionPreprocess + 198
>> 	1   libobjc.A.dylib                     0x00007fff9681e3f0
>> objc_exception_throw + 43
>> 	2   CoreFoundation                      0x00007fff8e6c9e7c
>> +[NSException raise:format:] + 204
>> 	3   AppKit                              0x00007fff951b2c29
>> _NSCreateWindowWithOpaqueShape2 + 655
>> 	4   AppKit                              0x00007fff951b1420 -[NSWindow
>> _commonAwake] + 2002
>> 	5   AppKit                              0x00007fff9516fe62 -[NSWindow
>> _commonInitFrame:styleMask:backing:defer:] + 1763
>> 	6   AppKit                              0x00007fff9516efaf -[NSWindow
>> _initContent:styleMask:backing:defer:contentView:] + 1568
>> 	7   AppKit                              0x00007fff9516e97f -[NSWindow
>> initWithContentRect:styleMask:backing:defer:] + 45
>> 	8   SDL                                 0x0000000102f515cc
>> SDL_SoftStretch + 24672
>> 	9   SDL                                 0x0000000102f4fe38
>> SDL_SoftStretch + 18636
>> 	10  SDL                                 0x0000000102f44da1
>> SDL_SetVideoMode + 892
>> 	11  Racket                              0x00000001002be82c ffi_call_unix64 + 76
>> 	12  ???                                 0x00007fff5fbfd8d0 0x0 +
>> 140734799796432
>> )
>> libc++abi.dylib: terminate called throwing an exception
>> Abort trap: 6
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