Mercurial > sdl-ios-xcode

view docs/html/sdlgetrgb.html @ 2787:93764fe8601a

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
It turns out both the software and the OpenGL renderer had the same problem. According to the spec, when SDL_SRCALPHA is set, the colorkey is ignored, so we just need to convert the colorkey into the alpha channel.
author Sam Lantinga <slouken@libsdl.org>
date Tue, 25 Nov 2008 05:29:14 +0000
parents 355632dca928
children
line wrap: on
line source

<HTML
><HEAD
><TITLE
>SDL_GetRGB</TITLE
><META
NAME="GENERATOR"
CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+
"><LINK
REL="HOME"
TITLE="SDL Library Documentation"
HREF="index.html"><LINK
REL="UP"
TITLE="Video"
HREF="video.html"><LINK
REL="PREVIOUS"
TITLE="SDL_MapRGBA"
HREF="sdlmaprgba.html"><LINK
REL="NEXT"
TITLE="SDL_GetRGBA"
HREF="sdlgetrgba.html"></HEAD
><BODY
CLASS="REFENTRY"
BGCOLOR="#FFF8DC"
TEXT="#000000"
LINK="#0000ee"
VLINK="#551a8b"
ALINK="#ff0000"
><DIV
CLASS="NAVHEADER"
><TABLE
SUMMARY="Header navigation table"
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TH
COLSPAN="3"
ALIGN="center"
>SDL Library Documentation</TH
></TR
><TR
><TD
WIDTH="10%"
ALIGN="left"
VALIGN="bottom"
><A
HREF="sdlmaprgba.html"
ACCESSKEY="P"
>Prev</A
></TD
><TD
WIDTH="80%"
ALIGN="center"
VALIGN="bottom"
></TD
><TD
WIDTH="10%"
ALIGN="right"
VALIGN="bottom"
><A
HREF="sdlgetrgba.html"
ACCESSKEY="N"
>Next</A
></TD
></TR
></TABLE
><HR
ALIGN="LEFT"
WIDTH="100%"></DIV
><H1
><A
NAME="SDLGETRGB"
></A
>SDL_GetRGB</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN1718"
></A
><H2
>Name</H2
>SDL_GetRGB&nbsp;--&nbsp;Get RGB values from a pixel in the specified pixel format.</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN1721"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN1722"
></A
><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>void <B
CLASS="FSFUNC"
>SDL_GetRGB</B
></CODE
>(Uint32 pixel, SDL_PixelFormat *fmt, Uint8 *r, Uint8 *g, Uint8 *b);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN1728"
></A
><H2
>Description</H2
><P
>Get RGB component values from a pixel stored in the specified pixel format.</P
><P
>This function uses the entire 8-bit [0..255] range when converting color
components from pixel formats with less than 8-bits per RGB component
(e.g., a completely white pixel in 16-bit RGB565 format would return
[0xff, 0xff, 0xff] not [0xf8, 0xfc, 0xf8]).</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN1732"
></A
><H2
>See Also</H2
><P
><A
HREF="sdlgetrgba.html"
><TT
CLASS="FUNCTION"
>SDL_GetRGBA</TT
></A
>,
<A
HREF="sdlmaprgb.html"
><TT
CLASS="FUNCTION"
>SDL_MapRGB</TT
></A
>,
<A
HREF="sdlmaprgba.html"
><TT
CLASS="FUNCTION"
>SDL_MapRGBA</TT
></A
>,
<A
HREF="sdlpixelformat.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_PixelFormat</SPAN
></A
></P
></DIV
><DIV
CLASS="NAVFOOTER"
><HR
ALIGN="LEFT"
WIDTH="100%"><TABLE
SUMMARY="Footer navigation table"
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
><A
HREF="sdlmaprgba.html"
ACCESSKEY="P"
>Prev</A
></TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="index.html"
ACCESSKEY="H"
>Home</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
><A
HREF="sdlgetrgba.html"
ACCESSKEY="N"
>Next</A
></TD
></TR
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
>SDL_MapRGBA</TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="video.html"
ACCESSKEY="U"
>Up</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
>SDL_GetRGBA</TD
></TR
></TABLE
></DIV
></BODY
></HTML
>