view docs/html/sdlactiveevent.html @ 968:4675910b0b7b

Date: Mon, 11 Oct 2004 15:17:27 +0300 (EEST) From: Hannu Savolainen Subject: Re: SDL uses obsolete OSS features I did some work on getting OSS to work better with SDL. There have been some problems with select which should be fixed now. I'm having some problems in understanding what is the purpose of the DSP_WaitAudio() routine. I added a return to the very beginning of this routine and commendted out the define for USE_BLOCKING_WRITES. At least lbreakout2 seems to work as well as earlier. The latencies are the same. An ordinary blocking write does exactly the same thing than DSP_WaitAudio does. So I would recommend using the USE_BLOCKING_WRITES approach and removing everything from the DSP_WaitAudio routine. Also enabling USE_BLOCKING_WRITES makes it possible to simplify DSP_PlayAudio() because you don't need to handle the partial writes (the do-while loop). Attached is a patch against SDL-1.2.7. After these changes SDL will use OSS as it's designed to be used (make it as simple as possible). This code should work with all OSS implementations because it uses only the very fundamental features that have been there since the jurassic times.
author Sam Lantinga <slouken@libsdl.org>
date Fri, 12 Nov 2004 21:39:04 +0000
parents 355632dca928
children
line wrap: on
line source

<HTML
><HEAD
><TITLE
>SDL_ActiveEvent</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_Event"
HREF="sdlevent.html"><LINK
REL="NEXT"
TITLE="SDL_KeyboardEvent"
HREF="sdlkeyboardevent.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="sdlevent.html"
ACCESSKEY="P"
>Prev</A
></TD
><TD
WIDTH="80%"
ALIGN="center"
VALIGN="bottom"
></TD
><TD
WIDTH="10%"
ALIGN="right"
VALIGN="bottom"
><A
HREF="sdlkeyboardevent.html"
ACCESSKEY="N"
>Next</A
></TD
></TR
></TABLE
><HR
ALIGN="LEFT"
WIDTH="100%"></DIV
><H1
><A
NAME="SDLACTIVEEVENT"
></A
>SDL_ActiveEvent</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN3955"
></A
><H2
>Name</H2
>SDL_ActiveEvent&nbsp;--&nbsp;Application visibility event structure</DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN3958"
></A
><H2
>Structure Definition</H2
><PRE
CLASS="PROGRAMLISTING"
>typedef struct{
  Uint8 type;
  Uint8 gain;
  Uint8 state;
} SDL_ActiveEvent;</PRE
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN3961"
></A
><H2
>Structure Data</H2
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN3963"
></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_ACTIVEEVENT.</TT
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>gain</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>0 if the event is a loss or 1 if it is a gain.</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>state</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="LITERAL"
>SDL_APPMOUSEFOCUS</TT
> if mouse focus was gained or lost, <TT
CLASS="LITERAL"
>SDL_APPINPUTFOCUS</TT
> if input focus was gained or lost, or <TT
CLASS="LITERAL"
>SDL_APPACTIVE</TT
> if the application was iconified (<TT
CLASS="STRUCTFIELD"
><I
>gain</I
></TT
>=0) or restored(<TT
CLASS="STRUCTFIELD"
><I
>gain</I
></TT
>=1).</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN3984"
></A
><H2
>Description</H2
><P
><SPAN
CLASS="STRUCTNAME"
>SDL_ActiveEvent</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_ACTIVEEVENT</TT
> is reported.</P
><P
>When the mouse leaves or enters the window area a <TT
CLASS="LITERAL"
>SDL_APPMOUSEFOCUS</TT
> type activation event occurs, if the mouse entered the window then <TT
CLASS="STRUCTFIELD"
><I
>gain</I
></TT
> will be 1, otherwise <TT
CLASS="STRUCTFIELD"
><I
>gain</I
></TT
> will be 0. A <TT
CLASS="LITERAL"
>SDL_APPINPUTFOCUS</TT
> type activation event occurs when the application loses or gains keyboard focus. This usually occurs when another application is made active. Finally, a <TT
CLASS="LITERAL"
>SDL_APPACTIVE</TT
> type event occurs when the application is either minimised/iconified (<TT
CLASS="STRUCTFIELD"
><I
>gain</I
></TT
>=0) or restored.</P
><DIV
CLASS="NOTE"
><BLOCKQUOTE
CLASS="NOTE"
><P
><B
>Note: </B
>This event does not occur when an application window is first created.</P
></BLOCKQUOTE
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN4000"
></A
><H2
>See Also</H2
><P
><A
HREF="sdlevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Event</SPAN
></A
>,
<A
HREF="sdlgetappstate.html"
><TT
CLASS="FUNCTION"
>SDL_GetAppState</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="sdlevent.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="sdlkeyboardevent.html"
ACCESSKEY="N"
>Next</A
></TD
></TR
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
>SDL_Event</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_KeyboardEvent</TD
></TR
></TABLE
></DIV
></BODY
></HTML
>