Mercurial > sdl-ios-xcode
view docs/html/event.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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<HTML ><HEAD ><TITLE >Events</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 Reference" HREF="reference.html"><LINK REL="PREVIOUS" TITLE="SDL_WM_GrabInput" HREF="sdlwmgrabinput.html"><LINK REL="NEXT" TITLE="SDL Event Structures." HREF="eventstructures.html"><META NAME="KEYWORD" CONTENT="events"><META NAME="KEYWORD" CONTENT="function"></HEAD ><BODY CLASS="CHAPTER" 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="sdlwmgrabinput.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="eventstructures.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="CHAPTER" ><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 NAME="AEN3691" ></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 ></DIV ></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="sdlwmgrabinput.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="eventstructures.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >SDL_WM_GrabInput</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="reference.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >SDL Event Structures.</TD ></TR ></TABLE ></DIV ></BODY ></HTML >