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Date: Sun, 22 Mar 2009 12:52:29 +0000 From: Luke Benstead Subject: OpenGL 3.0 Context Creation I've attached a patch which implements OpenGL 3.x context creation on the latest SVN. I've added two options to SDL_GL_SetAttribute, these are SDL_GL_CONTEXT_MAJOR_VERSION and SDL_GL_CONTEXT_MINOR_VERSION. These default to 2 and 1 respectively. If the major version is less than 3 then the current context creation method is used, otherwise the appropriate new context creation function is called (depending on the platform). Sample code: if (SDL_Init(SDL_INIT_VIDEO) != 0) { printf("Unable to initialize SDL: %s\n", SDL_GetError()); return 1; } SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3); //Without these 2 lines, SDL will create a GL 2.x context SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0); SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1); SDL_Surface* screen = SDL_SetVideoMode( 640, 480, 16, SDL_OPENGL | SDL_FULLSCREEN ); I've implemented context creation on both Win32 and X and run basic tests on both. This patch doesn't provide access to all the options allowed by the new context creation (e.g. shared contexts, forward compatible contexts) but they can be added pretty easily.
author Sam Lantinga <slouken@libsdl.org>
date Tue, 24 Mar 2009 10:43:53 +0000
parents 355632dca928
children
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<HTML
><HEAD
><TITLE
>Audio</TITLE
><META
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CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+
"><LINK
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><DIV
CLASS="CHAPTER"
><H1
><A
NAME="AUDIO"
></A
>Chapter 10. Audio</H1
><DIV
CLASS="TOC"
><DL
><DT
><B
>Table of Contents</B
></DT
><DT
><A
HREF="sdlaudiospec.html"
>SDL_AudioSpec</A
>&nbsp;--&nbsp;Audio Specification Structure</DT
><DT
><A
HREF="sdlopenaudio.html"
>SDL_OpenAudio</A
>&nbsp;--&nbsp;Opens the audio device with the desired parameters.</DT
><DT
><A
HREF="sdlpauseaudio.html"
>SDL_PauseAudio</A
>&nbsp;--&nbsp;Pauses and unpauses the audio callback processing</DT
><DT
><A
HREF="sdlgetaudiostatus.html"
>SDL_GetAudioStatus</A
>&nbsp;--&nbsp;Get the current audio state</DT
><DT
><A
HREF="sdlloadwav.html"
>SDL_LoadWAV</A
>&nbsp;--&nbsp;Load a WAVE file</DT
><DT
><A
HREF="sdlfreewav.html"
>SDL_FreeWAV</A
>&nbsp;--&nbsp;Frees previously opened WAV data</DT
><DT
><A
HREF="sdlaudiocvt.html"
>SDL_AudioCVT</A
>&nbsp;--&nbsp;Audio Conversion Structure</DT
><DT
><A
HREF="sdlbuildaudiocvt.html"
>SDL_BuildAudioCVT</A
>&nbsp;--&nbsp;Initializes a SDL_AudioCVT structure for conversion</DT
><DT
><A
HREF="sdlconvertaudio.html"
>SDL_ConvertAudio</A
>&nbsp;--&nbsp;Convert audio data to a desired audio format.</DT
><DT
><A
HREF="sdlmixaudio.html"
>SDL_MixAudio</A
>&nbsp;--&nbsp;Mix audio data</DT
><DT
><A
HREF="sdllockaudio.html"
>SDL_LockAudio</A
>&nbsp;--&nbsp;Lock out the callback function</DT
><DT
><A
HREF="sdlunlockaudio.html"
>SDL_UnlockAudio</A
>&nbsp;--&nbsp;Unlock the callback function</DT
><DT
><A
HREF="sdlcloseaudio.html"
>SDL_CloseAudio</A
>&nbsp;--&nbsp;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
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