Mercurial > sdl-ios-xcode
view docs/html/sdlgetrgba.html @ 2429:2c55b72ba46e gsoc2008_iphone
testdyngles is exactly what it sounds like -- a version of testdyngl that uses OpenGL ES calls instead of OpenGL. Was necessary to create because glOrtho is called glOrthof in OpenGL ES, and OpenGL ES doesn't have glBegin() type semantics for specifying geometry.
author | Holmes Futrell <hfutrell@umail.ucsb.edu> |
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date | Fri, 15 Aug 2008 00:52:52 +0000 |
parents | 355632dca928 |
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<HTML ><HEAD ><TITLE >SDL_GetRGBA</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_GetRGB" HREF="sdlgetrgb.html"><LINK REL="NEXT" TITLE="SDL_CreateRGBSurface" HREF="sdlcreatergbsurface.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="sdlgetrgb.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="sdlcreatergbsurface.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="SDLGETRGBA" ></A >SDL_GetRGBA</H1 ><DIV CLASS="REFNAMEDIV" ><A NAME="AEN1747" ></A ><H2 >Name</H2 >SDL_GetRGBA -- Get RGBA values from a pixel in the specified pixel format.</DIV ><DIV CLASS="REFSYNOPSISDIV" ><A NAME="AEN1750" ></A ><H2 >Synopsis</H2 ><DIV CLASS="FUNCSYNOPSIS" ><A NAME="AEN1751" ></A ><P ></P ><PRE CLASS="FUNCSYNOPSISINFO" >#include "SDL.h"</PRE ><P ><CODE ><CODE CLASS="FUNCDEF" >void <B CLASS="FSFUNC" >SDL_GetRGBA</B ></CODE >(Uint32 pixel, SDL_PixelFormat *fmt, Uint8 *r, Uint8 *g, Uint8 *b, Uint8 *a);</CODE ></P ><P ></P ></DIV ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN1757" ></A ><H2 >Description</H2 ><P >Get RGBA 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 ><P >If the surface has no alpha component, the alpha will be returned as 0xff (100% opaque).</P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN1762" ></A ><H2 >See Also</H2 ><P ><A HREF="sdlgetrgb.html" >SDL_GetRGB</A >, <A HREF="sdlmaprgb.html" >SDL_MapRGB</A >, <A HREF="sdlmaprgba.html" >SDL_MapRGBA</A >, <A HREF="sdlpixelformat.html" >SDL_PixelFormat</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="sdlgetrgb.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="sdlcreatergbsurface.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >SDL_GetRGB</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_CreateRGBSurface</TD ></TR ></TABLE ></DIV ></BODY ></HTML >