view docs/html/sdlcreatergbsurfacefrom.html @ 3880:74e828c64315 SDL-1.2

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 15:45:37 +0000
parents 355632dca928
children
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>SDL_CreateRGBSurfaceFrom</H1
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><H2
>Name</H2
>SDL_CreateRGBSurfaceFrom&nbsp;--&nbsp;Create an SDL_Surface from pixel data</DIV
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>Synopsis</H2
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><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>SDL_Surface *<B
CLASS="FSFUNC"
>SDL_CreateRGBSurfaceFrom</B
></CODE
>(void *pixels, int width, int height, int depth, int pitch, Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask);</CODE
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>Creates an SDL_Surface from the provided pixel data.</P
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>The data stored in <TT
CLASS="PARAMETER"
><I
>pixels</I
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> is assumed to be of the <TT
CLASS="PARAMETER"
><I
>depth</I
></TT
> specified in the parameter list. The pixel data is not copied into the <SPAN
CLASS="STRUCTNAME"
>SDL_Surface</SPAN
> structure so it should not be freed until the surface has been freed with a called to <A
HREF="sdlfreesurface.html"
>SDL_FreeSurface</A
>. <TT
CLASS="PARAMETER"
><I
>pitch</I
></TT
> is the length of each scanline in bytes.  </P
><P
>See <A
HREF="sdlcreatergbsurface.html"
><TT
CLASS="FUNCTION"
>SDL_CreateRGBSurface</TT
></A
> for a more detailed description of the other parameters.</P
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><H2
>Return Value</H2
><P
>Returns the created surface, or <SPAN
CLASS="RETURNVALUE"
>NULL</SPAN
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><A
HREF="sdlcreatergbsurface.html"
><TT
CLASS="FUNCTION"
>SDL_CreateRGBSurface</TT
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