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Updates for building on Windows CE using mingw32ce cross compiler: http://sourceforge.net/mailarchive/forum.php?thread_name 0703291652.38437.jwalt%40garni.ch&forum_name=cegcc-devel Hi! I just managed to compile SDL for Windows CE using the "mingw32ce" configuration of http://cegcc.sourceforge.net. Test programs work as expected (except for those using signals -- no POSIX on mingw32ce), and I didn't yet encounter any problem. While it was a pain to get everything compiled and running, the changes to SDL are actually quite small (see attached SDL-ce.diff). Unfortunately, the win32 headers shipped with cegcc are not 100% correct, and it feels quite messy to work around them in SDL code, so those headers will also need to be patched. (Attachment: win32api-ce.diff) Since I had to apply the libtool patch from the cegcc patch, I have also ad ded my copy of aclocal.m4 for SDL. I had to modify the cegcc libtool patch to use "lt_cv_deplibs_check_method=pass_all" for mingw32ce, otherwise libtool would not recognize the import libraries as valid for dynamic linking. All these changes should not affect non-WinCE builds, so they could be included in mainline SDL. If you need some docs, you can use this description for a cross-compilation README: 1) get cegcc from http://cegcc.sourceforge.net 2) build and install the "mingw32ce" variant (see cegcc installation docs) 3) patch w32api-headers (if not yet included in cegcc) 4) setup environment (customize the first three lines as you like): PREFIX=/opt/mingw32ce TARGET=arm-wince-mingw32ce BUILD=`uname -m`-pc-linux-gnu export PATH="$PREFIX/bin:$PREFIX/$TARGET/bin:$PREFIX/local/bin:$PATH" export CFLAGS="${CFLAGS:- -O2 -g} -I$PREFIX/local/include" export CPPFLAGS="${CPPFLAGS:- -O2 -g} -I$PREFIX/local/include" export CXXFLAGS="${CXXFLAGS:- -O2 -g} -I$PREFIX/local/include" export LDFLAGS="${LDFLAGS:- -O2 -g} -L$PREFIX/local/lib" export HOST_CC="gcc" export CC="$PREFIX/bin/$TARGET-gcc" export CXX="$PREFIX/bin/$TARGET-g++" export LD="$PREFIX/bin/$TARGET-ld" export AS="$PREFIX/bin/$TARGET-as" export AR="$PREFIX/bin/$TARGET-ar" export RANLIB="$PREFIX/bin/$TARGET-ranlib" export CONFIG_SHELL="/bin/sh" 5) build and install ./configure --target=$TARGET --host=$TARGET --build=$BUILD make make install 6) use (4) and (5) for any SDL-using software you want to cross-compile 7) copy $PREFIX/local/bin/SDL-1-2-0.dll into your executable directory on the WinCE machine
author Sam Lantinga <slouken@libsdl.org>
date Thu, 03 Jan 2008 06:19:07 +0000
parents 355632dca928
children
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<HTML
><HEAD
><TITLE
>Audio</TITLE
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><DIV
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><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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