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To: sdl@libsdl.org From: Christian Walther <cwalther@gmx.ch> Date: Wed, 28 Dec 2005 12:13:20 +0100 Subject: [SDL] Fix for opening documents on Mac OS X < 10.4 The current code in SDLMain.m that transforms documents opened from the Finder into command-line arguments (introduced in revision 1.14, 2005-08-11) uses the methods -[NSString lengthOfBytesUsingEncoding:] and -[NSString getCString:maxLength:encoding:], which are only available in Mac OS X 10.4. Compiling this code on 10.3 produces warnings, and running it (i.e. starting an SDL application by opening a document) leads to weird behavior which I didn't investigate in detail ("*** -[NSCFString lengthOfBytesUsingEncoding:]: selector not recognized" is printed to the console log, and the SDL window never opens). The attached patch removes the offending calls and uses -[NSString UTF8String] instead, which is available everywhere. Tested on 10.3.9, and I see no reason why it shouldn't also work on 10.2 and 10.4. Two further comments: * The comment above the -[SDLMain application: openFile:] implementation says "You need to have a CFBundleDocumentsType section in your Info.plist to get this message, apparently." This is not the case in my experience - it worked just fine with a hand-built bare-bones application consisting only of Test.app/Contents/MacOS/test, without any Info.plist (although you have to press the option and command keys for such an application to accept a dragged file). * I took the liberty of cleaning up another area of SDLMain.m: I changed "CustomApplicationMain (argc, argv)" to "CustomApplicationMain (int argc, char **argv)". This avoids the "type of `argv' defaults to `int'" warnings, and I'm not sure if leaving out the types could cause problems on platforms where an int and a char** aren't of the same size. -Christian
author Ryan C. Gordon <icculus@icculus.org>
date Sun, 01 Jan 2006 23:45:52 +0000
parents 355632dca928
children
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<HTML
><HEAD
><TITLE
>Audio</TITLE
><META
NAME="GENERATOR"
CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+
"><LINK
REL="HOME"
TITLE="SDL Library Documentation"
HREF="index.html"><LINK
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HREF="reference.html"><LINK
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TITLE="SDL_AudioSpec"
HREF="sdlaudiospec.html"><META
NAME="KEYWORD"
CONTENT="audio"><META
NAME="KEYWORD"
CONTENT="function"></HEAD
><BODY
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><HR
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><DIV
CLASS="CHAPTER"
><H1
><A
NAME="AUDIO"
></A
>Chapter 10. Audio</H1
><DIV
CLASS="TOC"
><DL
><DT
><B
>Table of Contents</B
></DT
><DT
><A
HREF="sdlaudiospec.html"
>SDL_AudioSpec</A
>&nbsp;--&nbsp;Audio Specification Structure</DT
><DT
><A
HREF="sdlopenaudio.html"
>SDL_OpenAudio</A
>&nbsp;--&nbsp;Opens the audio device with the desired parameters.</DT
><DT
><A
HREF="sdlpauseaudio.html"
>SDL_PauseAudio</A
>&nbsp;--&nbsp;Pauses and unpauses the audio callback processing</DT
><DT
><A
HREF="sdlgetaudiostatus.html"
>SDL_GetAudioStatus</A
>&nbsp;--&nbsp;Get the current audio state</DT
><DT
><A
HREF="sdlloadwav.html"
>SDL_LoadWAV</A
>&nbsp;--&nbsp;Load a WAVE file</DT
><DT
><A
HREF="sdlfreewav.html"
>SDL_FreeWAV</A
>&nbsp;--&nbsp;Frees previously opened WAV data</DT
><DT
><A
HREF="sdlaudiocvt.html"
>SDL_AudioCVT</A
>&nbsp;--&nbsp;Audio Conversion Structure</DT
><DT
><A
HREF="sdlbuildaudiocvt.html"
>SDL_BuildAudioCVT</A
>&nbsp;--&nbsp;Initializes a SDL_AudioCVT structure for conversion</DT
><DT
><A
HREF="sdlconvertaudio.html"
>SDL_ConvertAudio</A
>&nbsp;--&nbsp;Convert audio data to a desired audio format.</DT
><DT
><A
HREF="sdlmixaudio.html"
>SDL_MixAudio</A
>&nbsp;--&nbsp;Mix audio data</DT
><DT
><A
HREF="sdllockaudio.html"
>SDL_LockAudio</A
>&nbsp;--&nbsp;Lock out the callback function</DT
><DT
><A
HREF="sdlunlockaudio.html"
>SDL_UnlockAudio</A
>&nbsp;--&nbsp;Unlock the callback function</DT
><DT
><A
HREF="sdlcloseaudio.html"
>SDL_CloseAudio</A
>&nbsp;--&nbsp;Shuts down audio processing and closes the audio device.</DT
></DL
></DIV
><P
>Sound on the computer is translated from waves that you hear into a series of 
values, or samples, each representing the amplitude of the wave.  When these
samples are sent in a stream to a sound card, an approximation of the original
wave can be recreated.  The more bits used to represent the amplitude, and the
greater frequency these samples are gathered, the closer the approximated
sound is to the original, and the better the quality of sound.</P
><P
>This library supports both 8 and 16 bit signed and unsigned sound samples,
at frequencies ranging from 11025 Hz to 44100 Hz, depending on the 
underlying hardware.  If the hardware doesn't support the desired audio
format or frequency, it can be emulated if desired (See 
<A
HREF="sdlopenaudio.html"
><TT
CLASS="FUNCTION"
>SDL_OpenAudio()</TT
></A
>)</P
><P
>A commonly supported audio format is 16 bits per sample at 22050 Hz.</P
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