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HandleEvent() returns done each time it is called. If done was set to 0 the program should quit, but because done is not checked until *all* events are handled a following event can reset done to 1 and prevent the program from terminating when told to. I fixed the while loop that handles events to check for the state of done after handling each event. That could leave some events unhandled when the program exits, but it ensures that the program will exit.
author Bob Pendleton <bob@pendleton.com>
date Wed, 20 Feb 2008 23:27:33 +0000
parents 355632dca928
children
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<HTML
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>SDL_JoyBallEvent</TITLE
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><H1
><A
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>SDL_JoyBallEvent</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN4396"
></A
><H2
>Name</H2
>SDL_JoyBallEvent&nbsp;--&nbsp;Joystick trackball motion event structure</DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN4399"
></A
><H2
>Structure Definition</H2
><PRE
CLASS="PROGRAMLISTING"
>typedef struct{
  Uint8 type;
  Uint8 which;
  Uint8 ball;
  Sint16 xrel, yrel;
} SDL_JoyBallEvent;</PRE
></DIV
><DIV
CLASS="REFSECT1"
><A
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></A
><H2
>Structure Data</H2
><DIV
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></A
><P
></P
><TABLE
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><TBODY
><TR
><TD
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><TT
CLASS="STRUCTFIELD"
><I
>type</I
></TT
></TD
><TD
ALIGN="LEFT"
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><TT
CLASS="LITERAL"
>SDL_JOYBALLMOTION</TT
></TD
></TR
><TR
><TD
ALIGN="LEFT"
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><TT
CLASS="STRUCTFIELD"
><I
>which</I
></TT
></TD
><TD
ALIGN="LEFT"
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>Joystick device index</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>ball</I
></TT
></TD
><TD
ALIGN="LEFT"
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>Joystick trackball index</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"
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>The relative motion in the X/Y direction</TD
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><DIV
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><A
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><H2
>Description</H2
><P
><SPAN
CLASS="STRUCTNAME"
>SDL_JoyBallEvent</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_JOYBALLMOTION</TT
> is reported.</P
><P
>A <TT
CLASS="LITERAL"
>SDL_JOYBALLMOTION</TT
> event occurs when a user moves a trackball on the joystick. The field <TT
CLASS="STRUCTFIELD"
><I
>which</I
></TT
> is the index of the joystick that reported the event and <TT
CLASS="STRUCTFIELD"
><I
>ball</I
></TT
> is the index of the trackball (for a more detailed explaination see the <A
HREF="joystick.html"
>Joystick section</A
>). Trackballs only return relative motion, this is the change in position on the ball since it was last polled (last cycle of the event loop) and it is stored in <TT
CLASS="STRUCTFIELD"
><I
>xrel</I
></TT
> and <TT
CLASS="STRUCTFIELD"
><I
>yrel</I
></TT
>.</P
></DIV
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></A
><H2
>See Also</H2
><P
><A
HREF="sdlevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Event</SPAN
></A
>,
<A
HREF="joystick.html"
>Joystick Functions</A
>,
<A
HREF="sdljoystickeventstate.html"
><TT
CLASS="FUNCTION"
>SDL_JoystickEventState</TT
></A
>,
<A
HREF="sdljoystickgetball.html"
><TT
CLASS="FUNCTION"
>SDL_JoystickGetBall</TT
></A
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