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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
>Events</TITLE
><META
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CONTENT="events"><META
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><DIV
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><H1
><A
NAME="EVENT"
></A
>Chapter 8. Events</H1
><DIV
CLASS="TOC"
><DL
><DT
><B
>Table of Contents</B
></DT
><DT
><A
HREF="event.html#AEN3691"
>Introduction</A
></DT
><DT
><A
HREF="eventstructures.html"
>SDL Event Structures.</A
></DT
><DT
><A
HREF="eventfunctions.html"
>Event Functions.</A
></DT
></DL
></DIV
><DIV
CLASS="SECT1"
><H1
CLASS="SECT1"
><A
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></A
>Introduction</H1
><P
>Event handling allows your application to receive input from the user. Event handling is initalised (along with video) with a call to:
<PRE
CLASS="PROGRAMLISTING"
>SDL_Init(SDL_INIT_VIDEO);</PRE
>
Internally, SDL stores all the events waiting to be handled in an event queue. Using functions like <A
HREF="sdlpollevent.html"
><TT
CLASS="FUNCTION"
>SDL_PollEvent</TT
></A
> and <A
HREF="sdlpeepevents.html"
><TT
CLASS="FUNCTION"
>SDL_PeepEvents</TT
></A
> you can observe and handle waiting input events.</P
><P
>The key to event handling in SDL is the <A
HREF="sdlevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Event</SPAN
></A
> union. The event queue itself is composed of a series of <SPAN
CLASS="STRUCTNAME"
>SDL_Event</SPAN
> unions, one for each waiting event. <SPAN
CLASS="STRUCTNAME"
>SDL_Event</SPAN
> unions are read from the queue with the <TT
CLASS="FUNCTION"
>SDL_PollEvent</TT
> function and it is then up to the application to process the information stored with them.</P
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