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view docs/html/sdlkeyboardevent.html @ 3880:74e828c64315 SDL-1.2

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Fixed bug #292 I might be on crack here. It looks like SDL_ConvertMono() in src/audio/SDL_audiocvt.c adds the left and right channels of a stereo stream together, and clamps the new mono channel if it would overflow. Shouldn't it be dividing by 2 to average the two sample points instead of clamping? Otherwise the mono sample point's volume doubles in the conversion. This would also make the conversion faster, as it replaces two branches per sample frame with a bitwise shift. --ryan.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 24 Sep 2006 15:45:37 +0000
parents 355632dca928
children
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<HTML
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>SDL_KeyboardEvent</TITLE
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><H1
><A
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>SDL_KeyboardEvent</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN4011"
></A
><H2
>Name</H2
>SDL_KeyboardEvent&nbsp;--&nbsp;Keyboard event structure</DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN4014"
></A
><H2
>Structure Definition</H2
><PRE
CLASS="PROGRAMLISTING"
>typedef struct{
  Uint8 type;
  Uint8 state;
  SDL_keysym keysym;
} SDL_KeyboardEvent;</PRE
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN4017"
></A
><H2
>Structure Data</H2
><DIV
CLASS="INFORMALTABLE"
><A
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></A
><P
></P
><TABLE
BORDER="0"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>type</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="LITERAL"
>SDL_KEYDOWN</TT
> or <TT
CLASS="LITERAL"
>SDL_KEYUP</TT
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>state</I
></TT
></TD
><TD
ALIGN="LEFT"
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><TT
CLASS="LITERAL"
>SDL_PRESSED</TT
> or <TT
CLASS="LITERAL"
>SDL_RELEASED</TT
></TD
></TR
><TR
><TD
ALIGN="LEFT"
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><TT
CLASS="STRUCTFIELD"
><I
>keysym</I
></TT
></TD
><TD
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>Contains key press information</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
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><A
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></A
><H2
>Description</H2
><P
><SPAN
CLASS="STRUCTNAME"
>SDL_KeyboardEvent</SPAN
> is a member of the <A
HREF="sdlevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Event</SPAN
></A
> union and is used when an event of type <TT
CLASS="LITERAL"
>SDL_KEYDOWN</TT
> or <TT
CLASS="LITERAL"
>SDL_KEYUP</TT
> is reported.</P
><P
>The <TT
CLASS="STRUCTFIELD"
><I
>type</I
></TT
> and <TT
CLASS="STRUCTFIELD"
><I
>state</I
></TT
> actually report the same information, they just use different values to do it! A keyboard event occurs when a key is released (<TT
CLASS="STRUCTFIELD"
><I
>type</I
></TT
>=<TT
CLASS="LITERAL"
>SDK_KEYUP</TT
> or <TT
CLASS="STRUCTFIELD"
><I
>state</I
></TT
>=<TT
CLASS="LITERAL"
>SDL_RELEASED</TT
>) and when a key is pressed (<TT
CLASS="STRUCTFIELD"
><I
>type</I
></TT
>=<TT
CLASS="LITERAL"
>SDL_KEYDOWN</TT
> or <TT
CLASS="STRUCTFIELD"
><I
>state</I
></TT
>=<TT
CLASS="LITERAL"
>SDL_PRESSED</TT
>). The information on what key was pressed or released is in the <A
HREF="sdlkeysym.html"
><SPAN
CLASS="STRUCTNAME"
>keysym</SPAN
></A
> structure.</P
><DIV
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><BLOCKQUOTE
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><P
><B
>Note: </B
>Repeating <TT
CLASS="LITERAL"
>SDL_KEYDOWN</TT
> events will occur if key repeat is enabled (see <A
HREF="sdlenablekeyrepeat.html"
><TT
CLASS="FUNCTION"
>SDL_EnableKeyRepeat</TT
></A
>).</P
></BLOCKQUOTE
></DIV
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></A
><H2
>See Also</H2
><P
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><SPAN
CLASS="STRUCTNAME"
>SDL_Event</SPAN
></A
>,
<A
HREF="sdlkeysym.html"
><SPAN
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>SDL_keysym</SPAN
></A
>,
<A
HREF="sdlenablekeyrepeat.html"
><TT
CLASS="FUNCTION"
>SDL_EnableKeyRepeat</TT
></A
>,
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><TT
CLASS="FUNCTION"
>SDL_EnableUNICODE</TT
></A
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