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Steven Noonan to sdl While trying to build the SDLMain.m included with SDL 1.2.14, with #define SDL_USE_NIB_FILE 1: /Users/steven/Development/darwinia/targets/macosx/Darwinia/SDLMain.m: In function '-[SDLMain fixMenu:withAppName:]': /Users/steven/Development/darwinia/targets/macosx/Darwinia/SDLMain.m:122: warning: 'sizeToFit' is deprecated (declared at /Developer/SDKs/MacOSX10.6.sdk/System/Library/Frameworks/AppKit.framework/Headers/NSMenu.h:281) /Users/steven/Development/darwinia/targets/macosx/Darwinia/SDLMain.m: In function 'main': /Users/steven/Development/darwinia/targets/macosx/Darwinia/SDLMain.m:376: warning: 'poseAsClass:' is deprecated (declared at /Developer/SDKs/MacOSX10.6.sdk/System/Library/Frameworks/Foundation.framework/Headers/NSObject.h:127) /Users/steven/Development/darwinia/targets/macosx/Darwinia/SDLMain.m:376: error: 'poseAsClass:' is unavailable (declared at /Developer/SDKs/MacOSX10.6.sdk/System/Library/Frameworks/Foundation.framework/Headers/NSObject.h:127) /Users/steven/Development/darwinia/targets/macosx/Darwinia/SDLMain.m:377: warning: passing argument 2 of 'NSApplicationMain' from incompatible pointer type Eric Wing to Sam I don't have time today to look at this in detail, but the problem is definitely the poseAsClass: method. This was deprecated in Obj-C 2.0 and not retained in 64-bit. I've never used this method and it has always been limited to esoteric uses. I think this is why Apple wanted to dump it (among complicating some other things they do). I have read about others getting bit by this when migrating. Long story short, there really isn't a migration path for this method. The question that then must be asked is why are we using it (what does it accomplish), and then figure out the 'proper' way of accomplishing that. Glancing at SDLMain.m, it's not obvious to me why it is there or what it is really accomplishing. My only speculation is that NSApplicationMain hardcodes something to look for NSApplication and a subclass (SDLApplication) fails for some reason (assuming that the original coder did this for good reason). Three thoughts come to mind. 1) The Info.plist has properties to control things related to the startup class and nib. NSPrincipalClass, NSMainNibFile Maybe principle class needs to be SDLApplication and we can delete the poseAs 2) I was told that 10.6 introduced new APIs to make programatic NIB wrangling and avoidance easier. Unfortunately, I don't know the specifics. 3) Instead of subclassing NSApplication in SDLMain.m, maybe we can just add a category. It looks like the following is the only thing that is done (quick glance): @interface SDLApplication : NSApplication @end @implementation SDLApplication /* Invoked from the Quit menu item */ - (void)terminate:(id)sender { /* Post a SDL_QUIT event */ SDL_Event event; event.type = SDL_QUIT; SDL_PushEvent(&event); } @end So instead, we change this to: (warning written in mail and untested) @interface NSApplication (SDLApplication) - (void) terminate:(id)sender; @end @implementation NSApplication (SDLApplication) /* Invoked from the Quit menu item */ - (void)terminate:(id)sender { /* Post a SDL_QUIT event */ SDL_Event event; event.type = SDL_QUIT; SDL_PushEvent(&event); } @end Then everywhere SDLApplication is used, we change it to NSApplication (and remove the poseAsClass line). Perhaps you could ask the bug reporter to try this solution (#3). And if that fails, maybe try #1. -Eric Steven Noonan to Sam The suggested change (diff below) seems to work fine. - Steven
author Sam Lantinga <slouken@libsdl.org>
date Mon, 12 Oct 2009 21:07:12 +0000
parents 355632dca928
children
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<HTML
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>SDL_AudioCVT</TITLE
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><H1
><A
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>SDL_AudioCVT</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN6884"
></A
><H2
>Name</H2
>SDL_AudioCVT&nbsp;--&nbsp;Audio Conversion Structure</DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN6887"
></A
><H2
>Structure Definition</H2
><PRE
CLASS="PROGRAMLISTING"
>typedef struct{
  int needed;
  Uint16 src_format;
  Uint16 dest_format;
  double rate_incr;
  Uint8 *buf;
  int len;
  int len_cvt;
  int len_mult;
  double len_ratio;
  void (*filters[10])(struct SDL_AudioCVT *cvt, Uint16 format);
  int filter_index;
} SDL_AudioCVT;</PRE
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN6890"
></A
><H2
>Structure Data</H2
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN6892"
></A
><P
></P
><TABLE
BORDER="0"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>needed</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Set to one if the conversion is possible</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>src_format</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Audio format of the source</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>dest_format</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Audio format of the destination</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>rate_incr</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Rate conversion increment</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>buf</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Audio buffer</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>len</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Length of the original audio buffer in bytes</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>len_cvt</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Length of converted audio buffer in bytes (calculated)</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>len_mult</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>buf</I
></TT
> must be <TT
CLASS="STRUCTFIELD"
><I
>len</I
></TT
>*<TT
CLASS="STRUCTFIELD"
><I
>len_mult</I
></TT
> bytes in size(calculated)</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>len_ratio</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Final audio size is <TT
CLASS="STRUCTFIELD"
><I
>len</I
></TT
>*<TT
CLASS="STRUCTFIELD"
><I
>len_ratio</I
></TT
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>filters[10](..)</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Pointers to functions needed for this conversion</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>filter_index</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Current conversion function</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN6944"
></A
><H2
>Description</H2
><P
>The <SPAN
CLASS="STRUCTNAME"
>SDL_AudioCVT</SPAN
> is used to convert audio data between different formats. A <SPAN
CLASS="STRUCTNAME"
>SDL_AudioCVT</SPAN
> structure is created with the <A
HREF="sdlbuildaudiocvt.html"
><TT
CLASS="FUNCTION"
>SDL_BuildAudioCVT</TT
></A
> function, while the actual conversion is done by the <A
HREF="sdlconvertaudio.html"
><TT
CLASS="FUNCTION"
>SDL_ConvertAudio</TT
></A
> function.</P
><P
>Many of the fields in the <SPAN
CLASS="STRUCTNAME"
>SDL_AudioCVT</SPAN
> structure should be considered private and their function will not be discussed here.</P
><P
></P
><DIV
CLASS="VARIABLELIST"
><DL
><DT
><SPAN
CLASS="TYPE"
>Uint8 *</SPAN
><TT
CLASS="STRUCTFIELD"
><I
>buf</I
></TT
></DT
><DD
><P
>This points to the audio data that will be used in the conversion. It is both the source and the destination, which means the converted audio data overwrites the original data. It also means that the converted data may be larger than the original data (if you were converting from 8-bit to 16-bit, for instance), so you must ensure <TT
CLASS="STRUCTFIELD"
><I
>buf</I
></TT
> is large enough. See below.</P
></DD
><DT
><SPAN
CLASS="TYPE"
>int</SPAN
> <TT
CLASS="STRUCTFIELD"
><I
>len</I
></TT
></DT
><DD
><P
>This is the length of the original audio data in bytes.</P
></DD
><DT
><SPAN
CLASS="TYPE"
>int</SPAN
> <TT
CLASS="STRUCTFIELD"
><I
>len_mult</I
></TT
></DT
><DD
><P
>As explained above, the audio buffer needs to be big enough to store the converted data, which may be bigger than the original audio data. The length of <TT
CLASS="STRUCTFIELD"
><I
>buf</I
></TT
> should be <TT
CLASS="STRUCTFIELD"
><I
>len</I
></TT
>*<TT
CLASS="STRUCTFIELD"
><I
>len_mult</I
></TT
>.</P
></DD
><DT
><SPAN
CLASS="TYPE"
>double</SPAN
> <TT
CLASS="STRUCTFIELD"
><I
>len_ratio</I
></TT
></DT
><DD
><P
>When you have finished converting your audio data, you need to know how much of your audio buffer is valid. <TT
CLASS="STRUCTFIELD"
><I
>len</I
></TT
>*<TT
CLASS="STRUCTFIELD"
><I
>len_ratio</I
></TT
> is the size of the converted audio data in bytes. This is very similar to <TT
CLASS="STRUCTFIELD"
><I
>len_mult</I
></TT
>, however when the convert audio data is shorter than the original <TT
CLASS="STRUCTFIELD"
><I
>len_mult</I
></TT
> would be 1. <TT
CLASS="STRUCTFIELD"
><I
>len_ratio</I
></TT
>, on the other hand, would be a fractional number between 0 and 1.</P
></DD
></DL
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN6989"
></A
><H2
>See Also</H2
><P
><A
HREF="sdlbuildaudiocvt.html"
><TT
CLASS="FUNCTION"
>SDL_BuildAudioCVT</TT
></A
>,
<A
HREF="sdlconvertaudio.html"
><TT
CLASS="FUNCTION"
>SDL_ConvertAudio</TT
></A
>,
<A
HREF="sdlaudiospec.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_AudioSpec</SPAN
></A
></P
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