view docs/html/sdlbuildaudiocvt.html @ 883:50f5a29c6a17

Date: Sat, 10 Apr 2004 02:25:33 -0400 From: Glenn Maynard To: sdl@libsdl.org Subject: [SDL] SDL_SetVideoMode() failing and not setting an error (patch) Running an OpenGL SDL application off 1.2.7, at SDL_InitSubSystem(SDL_INIT_VIDEO) time: Warning: Unable to initialize AAlib mouseUsing AAlib driver: Slang driver 1.0 (slang) SDL_SetVideoMode then fails; SDL_GetError() returns "". The installation problem is straightforward: X (the higher priority driver) isn't running, so SDL is falling back on aalib. However, no error is being set when aalib fails to initialize. This also happens with the svgalib driver. SDL_video.c line ~653 sets mode to NULL, since aalib didn't return an OpenGL surface. Line ~711 ("failed setting a video mode") returns NULL. The attached patch sets an error. It's a horrible, useless error message--it should really say eg. "aalib does not support OpenGL"; this should probably be done earlier in the individual drivers, too.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 11 Apr 2004 19:54:40 +0000
parents 355632dca928
children
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><H1
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>SDL_BuildAudioCVT</H1
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><H2
>Name</H2
>SDL_BuildAudioCVT&nbsp;--&nbsp;Initializes a SDL_AudioCVT structure for conversion</DIV
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><H2
>Synopsis</H2
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><P
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><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>int <B
CLASS="FSFUNC"
>SDL_BuildAudioCVT</B
></CODE
>(SDL_AudioCVT *cvt, Uint16 src_format, Uint8 src_channels, int src_rate, Uint16 dst_format, Uint8 dst_channels, int dst_rate);</CODE
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><H2
>Description</H2
><P
>Before an <A
HREF="sdlaudiocvt.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_AudioCVT</SPAN
></A
> structure can be used to convert audio data it must be initialized with source and destination information. </P
><P
><TT
CLASS="PARAMETER"
><I
>src_format</I
></TT
> and <TT
CLASS="PARAMETER"
><I
>dst_format</I
></TT
> are the source and destination format of the conversion. (For information on audio formats see <A
HREF="sdlaudiospec.html"
><SPAN
CLASS="STRUCTNAME"
> SDL_AudioSpec</SPAN
></A
>). <TT
CLASS="PARAMETER"
><I
>src_channels</I
></TT
> and <TT
CLASS="PARAMETER"
><I
>dst_channels</I
></TT
> are the number of channels in the source and destination formats. Finally, <TT
CLASS="PARAMETER"
><I
>src_rate</I
></TT
> and <TT
CLASS="PARAMETER"
><I
>dst_rate</I
></TT
> are the frequency or samples-per-second of the source and destination formats. Once again, see <A
HREF="sdlaudiospec.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_AudioSpec</SPAN
></A
>.</P
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><A
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><H2
>Return Values</H2
><P
>Returns <SPAN
CLASS="RETURNVALUE"
>-1</SPAN
> if the filter could not be built or 1 if it could.</P
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><H2
>Examples</H2
><P
>See <A
HREF="sdlconvertaudio.html"
><TT
CLASS="FUNCTION"
>SDL_ConvertAudio</TT
></A
>.</P
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>See Also</H2
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><TT
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>SDL_ConvertAudio</TT
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>,
<A
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>SDL_AudioCVT</TT
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