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Date: 28 Jun 2003 22:42:52 +0100
From: Alan Swanson
Subject: Re: [SDL] New XFree 4.3 Video Mode Patch
I have a wee amendment that moves the qsort in set_best_resolution
to only occur after failing to find an exact match only. This would
make absolutely sure we get a user set mode.
While I've never had any problems for my normal resolutions (1280x1024,
1024x768, 800x600 & 640,480) while closely examining the output from
qsort I've noticed it doesn't seem to sort the modes fully. These is
one definite wrong at 1152x768 and a few that just look wrong to me.
From a program (attached) I made to examine this more easily. X has
sorted its mode list using the same method as ours (plus frequency),
and our user modes get inserted without any other movement.
On the patch I've made I've also changed cmpmodes to sort on vertical
resolution and then horizontal. Ie vertical is now most significant
bit.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Sat, 28 Jun 2003 21:52:26 +0000 |
parents | 55f1f1b3e27d |
children | 355632dca928 |
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<HTML ><HEAD ><TITLE >Audio</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.64 "><LINK REL="HOME" TITLE="SDL Library Documentation" HREF="index.html"><LINK REL="UP" TITLE="SDL Reference" HREF="reference.html"><LINK REL="PREVIOUS" TITLE="SDL_JoystickClose" HREF="sdljoystickclose.html"><LINK REL="NEXT" TITLE="SDL_AudioSpec" HREF="sdlaudiospec.html"><META NAME="KEYWORD" CONTENT="audio"><META NAME="KEYWORD" CONTENT="function"></HEAD ><BODY CLASS="CHAPTER" BGCOLOR="#FFF8DC" TEXT="#000000" LINK="#0000ee" VLINK="#551a8b" ALINK="#ff0000" ><DIV CLASS="NAVHEADER" ><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="sdljoystickclose.html" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="sdlaudiospec.html" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="CHAPTER" ><H1 ><A NAME="AUDIO" >Chapter 10. Audio</A ></H1 ><DIV CLASS="TOC" ><DL ><DT ><B >Table of Contents</B ></DT ><DT ><A HREF="sdlaudiospec.html" >SDL_AudioSpec</A > — Audio Specification Structure</DT ><DT ><A HREF="sdlopenaudio.html" >SDL_OpenAudio</A > — Opens the audio device with the desired parameters.</DT ><DT ><A HREF="sdlpauseaudio.html" >SDL_PauseAudio</A > — Pauses and unpauses the audio callback processing</DT ><DT ><A HREF="sdlgetaudiostatus.html" >SDL_GetAudioStatus</A > — Get the current audio state</DT ><DT ><A HREF="sdlloadwav.html" >SDL_LoadWAV</A > — Load a WAVE file</DT ><DT ><A HREF="sdlfreewav.html" >SDL_FreeWAV</A > — Frees previously opened WAV data</DT ><DT ><A HREF="sdlaudiocvt.html" >SDL_AudioCVT</A > — Audio Conversion Structure</DT ><DT ><A HREF="sdlbuildaudiocvt.html" >SDL_BuildAudioCVT</A > — Initializes a SDL_AudioCVT structure for conversion</DT ><DT ><A HREF="sdlconvertaudio.html" >SDL_ConvertAudio</A > — Convert audio data to a desired audio format.</DT ><DT ><A HREF="sdlmixaudio.html" >SDL_MixAudio</A > — Mix audio data</DT ><DT ><A HREF="sdllockaudio.html" >SDL_LockAudio</A > — Lock out the callback function</DT ><DT ><A HREF="sdlunlockaudio.html" >SDL_UnlockAudio</A > — Unlock the callback function</DT ><DT ><A HREF="sdlcloseaudio.html" >SDL_CloseAudio</A > — Shuts down audio processing and closes the audio device.</DT ></DL ></DIV ><P >Sound on the computer is translated from waves that you hear into a series of values, or samples, each representing the amplitude of the wave. When these samples are sent in a stream to a sound card, an approximation of the original wave can be recreated. The more bits used to represent the amplitude, and the greater frequency these samples are gathered, the closer the approximated sound is to the original, and the better the quality of sound.</P ><P >This library supports both 8 and 16 bit signed and unsigned sound samples, at frequencies ranging from 11025 Hz to 44100 Hz, depending on the underlying hardware. If the hardware doesn't support the desired audio format or frequency, it can be emulated if desired (See <A HREF="sdlopenaudio.html" ><TT CLASS="FUNCTION" >SDL_OpenAudio()</TT ></A >)</P ><P >A commonly supported audio format is 16 bits per sample at 22050 Hz.</P ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="sdljoystickclose.html" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="sdlaudiospec.html" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >SDL_JoystickClose</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="reference.html" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >SDL_AudioSpec</TD ></TR ></TABLE ></DIV ></BODY ></HTML >