Mercurial > sdl-ios-xcode
view docs/html/sdljoyballevent.html @ 2938:2929ed239d2a
Adjusted default choice of audio driver.
If a driver can definitely see available devices, it is chosen. Otherwise,
we'll take the first driver that initializes but saw no devices...this might
be because it can't enumerate them, or there really aren't any available.
This prevents the dsp driver from hogging control when there are no /dev/dsp*
nodes (for example, on a Linux box with ALSA and no OSS emulation).
author | Ryan C. Gordon <icculus@icculus.org> |
---|---|
date | Thu, 01 Jan 2009 07:54:58 +0000 |
parents | 355632dca928 |
children |
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<HTML ><HEAD ><TITLE >SDL_JoyBallEvent</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+ "><LINK REL="HOME" TITLE="SDL Library Documentation" HREF="index.html"><LINK REL="UP" TITLE="SDL Event Structures." HREF="eventstructures.html"><LINK REL="PREVIOUS" TITLE="SDL_JoyHatEvent" HREF="sdljoyhatevent.html"><LINK REL="NEXT" TITLE="SDL_ResizeEvent" HREF="sdlresizeevent.html"></HEAD ><BODY CLASS="REFENTRY" BGCOLOR="#FFF8DC" TEXT="#000000" LINK="#0000ee" VLINK="#551a8b" ALINK="#ff0000" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="3" ALIGN="center" >SDL Library Documentation</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="sdljoyhatevent.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="sdlresizeevent.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="SDLJOYBALLEVENT" ></A >SDL_JoyBallEvent</H1 ><DIV CLASS="REFNAMEDIV" ><A NAME="AEN4396" ></A ><H2 >Name</H2 >SDL_JoyBallEvent -- 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 NAME="AEN4402" ></A ><H2 >Structure Data</H2 ><DIV CLASS="INFORMALTABLE" ><A NAME="AEN4404" ></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_JOYBALLMOTION</TT ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >which</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >Joystick device index</TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >ball</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >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" VALIGN="TOP" >The relative motion in the X/Y direction</TD ></TR ></TBODY ></TABLE ><P ></P ></DIV ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN4425" ></A ><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 ><DIV CLASS="REFSECT1" ><A NAME="AEN4439" ></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 ></P ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="sdljoyhatevent.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="sdlresizeevent.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >SDL_JoyHatEvent</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="eventstructures.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >SDL_ResizeEvent</TD ></TR ></TABLE ></DIV ></BODY ></HTML >