view docs/html/sdlmousemotionevent.html @ 2042:3908e1f808e1

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 15:56:36 +0000
parents 355632dca928
children
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>SDL_MouseMotionEvent</TITLE
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><H1
><A
NAME="SDLMOUSEMOTIONEVENT"
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>SDL_MouseMotionEvent</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN4079"
></A
><H2
>Name</H2
>SDL_MouseMotionEvent&nbsp;--&nbsp;Mouse motion event structure</DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN4082"
></A
><H2
>Structure Definition</H2
><PRE
CLASS="PROGRAMLISTING"
>typedef struct{
  Uint8 type;
  Uint8 state;
  Uint16 x, y;
  Sint16 xrel, yrel;
} SDL_MouseMotionEvent;</PRE
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN4085"
></A
><H2
>Structure Data</H2
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN4087"
></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_MOUSEMOTION</TT
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>state</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>The current button state</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>x</I
></TT
>, <TT
CLASS="STRUCTFIELD"
><I
>y</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>The X/Y coordinates of the mouse</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>xrel</I
></TT
>, <TT
CLASS="STRUCTFIELD"
><I
>yrel</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Relative motion in the X/Y direction</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN4109"
></A
><H2
>Description</H2
><P
><SPAN
CLASS="STRUCTNAME"
>SDL_MouseMotionEvent</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_MOUSEMOTION</TT
> is reported.</P
><P
>Simply put, a <TT
CLASS="LITERAL"
>SDL_MOUSEMOTION</TT
> type event occurs when a user moves the mouse within the application window or when <A
HREF="sdlwarpmouse.html"
><TT
CLASS="FUNCTION"
>SDL_WarpMouse</TT
></A
> is called. Both the absolute (<TT
CLASS="STRUCTFIELD"
><I
>x</I
></TT
> and <TT
CLASS="STRUCTFIELD"
><I
>y</I
></TT
>) and relative (<TT
CLASS="STRUCTFIELD"
><I
>xrel</I
></TT
> and <TT
CLASS="STRUCTFIELD"
><I
>yrel</I
></TT
>) coordinates are reported along with the current button states (<TT
CLASS="STRUCTFIELD"
><I
>state</I
></TT
>). The button state can be interpreted using the <TT
CLASS="LITERAL"
>SDL_BUTTON</TT
> macro (see <A
HREF="sdlgetmousestate.html"
><TT
CLASS="FUNCTION"
>SDL_GetMouseState</TT
></A
>).</P
><P
>If the cursor is hidden (<A
HREF="sdlshowcursor.html"
><TT
CLASS="FUNCTION"
>SDL_ShowCursor</TT
>(0)</A
>) and the input is grabbed (<A
HREF="sdlwmgrabinput.html"
><TT
CLASS="FUNCTION"
>SDL_WM_GrabInput</TT
>(SDL_GRAB_ON)</A
>), then the mouse will give relative motion events even when the cursor reaches the edge fo the screen. This is currently only implemented on Windows and Linux/Unix-a-likes.</P
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><H2
>See Also</H2
><P
><A
HREF="sdlevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Event</SPAN
></A
>,
<A
HREF="sdlmousebuttonevent.html"
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>SDL_MouseButtonEvent</SPAN
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