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Significantly improved XIM support. Fixes Bugzilla #429. Selected notes from the patch's README: = FIXES = This patch fixes the above issues as follows. == X11 events == Moved XFilterEvent just after XNextEvent so that all events are passed to it. Also, XFilterEvent will receive masks indicated by IM through XNFilterEvents IC value as well as masks surpplied by SDL. X11_KeyRepeat is called between XNextEvent and XFilterEvent, after testing an event is a KeyRelease. I'm not 100% comfortable to do so, but I couldn't find a better timing to call it, and use of the function is inevitable. == Xutf8LookupString == Used a longer buffer to receive UTF-8 string. If it is insufficient, a dynamic storage of the requested size will be allocated. The initial size of the buffer is set to 32, because the Japanese text converted from the most widely used benchmark key sequence for Japanese IM, "WATASHINONAMAEHANAKANODESU." has ten Japanese characters in it, that occupies 30 bytes when encoded in UTF-8. == SDL_keysym.unicode == On Windows version of SDL implementation, SDL_keysym.unicode stores UTF-16 encoded unicode characters, one UTF-16 encoding unit per an SDL event. A Unicode supplementary characters are sent to an application as two events. (One with a high surrogate and another with a low surrogate.) The behavior seems reasonable since it is upward compatible with existing handling of BMP characters. I wrote a UTF-8 to UTF-16 conversion function for the purpose. It is designed with the execution speed in mind, having a minimum set of features that my patch requires.
author Ryan C. Gordon <icculus@icculus.org>
date Mon, 25 Jun 2007 19:58:32 +0000
parents 355632dca928
children
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<HTML
><HEAD
><TITLE
>SDL_AudioSpec</TITLE
><META
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><H1
><A
NAME="SDLAUDIOSPEC"
></A
>SDL_AudioSpec</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN6507"
></A
><H2
>Name</H2
>SDL_AudioSpec&nbsp;--&nbsp;Audio Specification Structure</DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN6510"
></A
><H2
>Structure Definition</H2
><PRE
CLASS="PROGRAMLISTING"
>typedef struct{
  int freq;
  Uint16 format;
  Uint8 channels;
  Uint8 silence;
  Uint16 samples;
  Uint32 size;
  void (*callback)(void *userdata, Uint8 *stream, int len);
  void *userdata;
} SDL_AudioSpec;</PRE
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN6513"
></A
><H2
>Structure Data</H2
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN6515"
></A
><P
></P
><TABLE
BORDER="0"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>freq</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Audio frequency in samples per second</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>format</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Audio data format</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>channels</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Number of channels: 1 mono, 2 stereo</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>silence</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Audio buffer silence value (calculated)</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>samples</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Audio buffer size in samples</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>size</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Audio buffer size in bytes (calculated)</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>callback(..)</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Callback function for filling the audio buffer</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>userdata</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Pointer the user data which is passed to the callback function</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN6550"
></A
><H2
>Description</H2
><P
>The <SPAN
CLASS="STRUCTNAME"
>SDL_AudioSpec</SPAN
> structure is used to describe the format of some audio data. This structure is used by <A
HREF="sdlopenaudio.html"
><TT
CLASS="FUNCTION"
>SDL_OpenAudio</TT
></A
> and <A
HREF="sdlloadwav.html"
><TT
CLASS="FUNCTION"
>SDL_LoadWAV</TT
></A
>. While all fields are used by <TT
CLASS="FUNCTION"
>SDL_OpenAudio</TT
> only <TT
CLASS="STRUCTFIELD"
><I
>freq</I
></TT
>, <TT
CLASS="STRUCTFIELD"
><I
>format</I
></TT
>, <TT
CLASS="STRUCTFIELD"
><I
>samples</I
></TT
> and <TT
CLASS="STRUCTFIELD"
><I
>channels</I
></TT
> are used by <TT
CLASS="FUNCTION"
>SDL_LoadWAV</TT
>. We will detail these common members here.</P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN6564"
></A
><P
></P
><TABLE
BORDER="0"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>freq</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><P
>The number of samples sent to the sound device every second. Common values are 11025, 22050 and 44100. The higher the better.</P
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>format</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><P
>Specifies the size and type of each sample element
<P
></P
><DIV
CLASS="VARIABLELIST"
><DL
><DT
><TT
CLASS="LITERAL"
>AUDIO_U8</TT
></DT
><DD
><P
>Unsigned 8-bit samples</P
></DD
><DT
><TT
CLASS="LITERAL"
>AUDIO_S8</TT
></DT
><DD
><P
>Signed 8-bit samples</P
></DD
><DT
><TT
CLASS="LITERAL"
>AUDIO_U16</TT
> or <TT
CLASS="LITERAL"
>AUDIO_U16LSB</TT
></DT
><DD
><P
>Unsigned 16-bit little-endian samples</P
></DD
><DT
><TT
CLASS="LITERAL"
>AUDIO_S16</TT
> or <TT
CLASS="LITERAL"
>AUDIO_S16LSB</TT
></DT
><DD
><P
>Signed 16-bit little-endian samples</P
></DD
><DT
><TT
CLASS="LITERAL"
>AUDIO_U16MSB</TT
></DT
><DD
><P
>Unsigned 16-bit big-endian samples</P
></DD
><DT
><TT
CLASS="LITERAL"
>AUDIO_S16MSB</TT
></DT
><DD
><P
>Signed 16-bit big-endian samples</P
></DD
><DT
><TT
CLASS="LITERAL"
>AUDIO_U16SYS</TT
></DT
><DD
><P
>Either <TT
CLASS="LITERAL"
>AUDIO_U16LSB</TT
> or <TT
CLASS="LITERAL"
>AUDIO_U16MSB</TT
> depending on you systems endianness</P
></DD
><DT
><TT
CLASS="LITERAL"
>AUDIO_S16SYS</TT
></DT
><DD
><P
>Either <TT
CLASS="LITERAL"
>AUDIO_S16LSB</TT
> or <TT
CLASS="LITERAL"
>AUDIO_S16MSB</TT
> depending on you systems endianness</P
></DD
></DL
></DIV
></P
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>channels</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>The number of seperate sound channels. 1 is mono (single channel), 2 is stereo (dual channel).</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>samples</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>When used with <A
HREF="sdlopenaudio.html"
><TT
CLASS="FUNCTION"
>SDL_OpenAudio</TT
></A
> this refers to the size of the audio buffer in samples. A sample a chunk of audio data of the size specified in <TT
CLASS="PARAMETER"
><I
>format</I
></TT
> mulitplied by the number of channels. When the <SPAN
CLASS="STRUCTNAME"
>SDL_AudioSpec</SPAN
> is used with <A
HREF="sdlloadwav.html"
><TT
CLASS="FUNCTION"
>SDL_LoadWAV</TT
></A
> <TT
CLASS="STRUCTFIELD"
><I
>samples</I
></TT
> is set to 4096.</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><DIV
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><A
NAME="AEN6639"
></A
><H2
>See Also</H2
><P
><A
HREF="sdlopenaudio.html"
><TT
CLASS="FUNCTION"
>SDL_OpenAudio</TT
></A
>,
<A
HREF="sdlloadwav.html"
><TT
CLASS="FUNCTION"
>SDL_LoadWAV</TT
></A
></P
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