view docs/html/sdlmaprgba.html @ 1614:6162b8d921ce

Date: Wed, 29 Mar 2006 17:26:55 +0200 CEST From: "Fran���is Revol" Subject: [SDL] BeOS port fix: PrintScreen key crashing It seems the latest SDL crashes when someone hits the PrtScrn key in ZETA (BeOS R6), somewhere it gets a negative value as key code (or a big unsigned maybe ?), and uses it as an index in the keysym table... I'll investigate the cause for the negative value, but it's always better to check for bounds correctly when indexing a table. The attached diff fixes it. Fran���is Revol -- Software Architect yellowTAB GmbH
author Sam Lantinga <slouken@libsdl.org>
date Fri, 31 Mar 2006 06:16:20 +0000
parents 355632dca928
children
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>SDL_MapRGBA</H1
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><H2
>Name</H2
>SDL_MapRGBA&nbsp;--&nbsp;Map a RGBA color value to a pixel format.</DIV
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>Synopsis</H2
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><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>Uint32 <B
CLASS="FSFUNC"
>SDL_MapRGBA</B
></CODE
>(SDL_PixelFormat *fmt, Uint8 r, Uint8 g, Uint8 b, Uint8 a);</CODE
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><H2
>Description</H2
><P
>Maps the RGBA color value to the specified pixel format and returns the
pixel value as a 32-bit int.</P
><P
>If the format has a palette (8-bit) the index of the closest matching
color in the palette will be returned.</P
><P
>If the specified pixel format has no alpha component the alpha value
will be ignored (as it will be in formats with a palette).</P
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CLASS="REFSECT1"
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NAME="AEN1702"
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><H2
>Return Value</H2
><P
>A pixel value best approximating the given RGBA color value for a given
pixel format. If the pixel format bpp (color depth) is less than 32-bpp
then the unused upper bits of the return value can safely be ignored
(e.g., with a 16-bpp format the return value can be assigned to a
<SPAN
CLASS="TYPE"
>Uint16</SPAN
>, and similarly a <SPAN
CLASS="TYPE"
>Uint8</SPAN
> for an 8-bpp
format).</P
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>See Also</H2
><P
><A
HREF="sdlgetrgb.html"
>SDL_GetRGB</A
>,
<A
HREF="sdlgetrgba.html"
>SDL_GetRGBA</A
>,
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HREF="sdlmaprgb.html"
>SDL_MapRGB</A
>,
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>SDL_PixelFormat</A
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