view docs/html/sdlfillrect.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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>SDL_FillRect</TITLE
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><H1
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>SDL_FillRect</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN2351"
></A
><H2
>Name</H2
>SDL_FillRect&nbsp;--&nbsp;This function performs a fast fill of the given rectangle with some color</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN2354"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN2355"
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><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>int <B
CLASS="FSFUNC"
>SDL_FillRect</B
></CODE
>(SDL_Surface *dst, SDL_Rect *dstrect, Uint32 color);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN2361"
></A
><H2
>Description</H2
><P
>This function performs a fast fill of the given rectangle with
<TT
CLASS="PARAMETER"
><I
>color</I
></TT
>.  If <TT
CLASS="PARAMETER"
><I
>dstrect</I
></TT
>
is <TT
CLASS="LITERAL"
>NULL</TT
>, the whole surface will be filled with
<TT
CLASS="PARAMETER"
><I
>color</I
></TT
>.</P
><P
>The color should be a pixel of the format used by the surface, and
can be generated by the
<A
HREF="sdlmaprgb.html"
>SDL_MapRGB</A
> or <A
HREF="sdlmaprgba.html"
>SDL_MapRGBA</A
>
functions. If the color value contains an alpha value then the
destination is simply "filled" with that alpha information, no blending
takes place.</P
><P
>If there is a clip rectangle set on the destination (set via
<A
HREF="sdlsetcliprect.html"
>SDL_SetClipRect</A
>) then this
function will clip based on the intersection of the clip rectangle and
the <TT
CLASS="PARAMETER"
><I
>dstrect</I
></TT
> rectangle and the dstrect rectangle
will be modified to represent the area actually filled.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN2374"
></A
><H2
>Return Value</H2
><P
>This function returns <SPAN
CLASS="RETURNVALUE"
>0</SPAN
> on success, or
<SPAN
CLASS="RETURNVALUE"
>-1</SPAN
> on error.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN2379"
></A
><H2
>See Also</H2
><P
><A
HREF="sdlmaprgb.html"
><TT
CLASS="FUNCTION"
>SDL_MapRGB</TT
></A
>,
<A
HREF="sdlmaprgb.html"
><TT
CLASS="FUNCTION"
>SDL_MapRGBA</TT
></A
>,
<A
HREF="sdlblitsurface.html"
><TT
CLASS="FUNCTION"
>SDL_BlitSurface</TT
></A
>,
<A
HREF="sdlrect.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Rect</SPAN
></A
></P
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