Mercurial > sdl-ios-xcode
annotate docs/html/sdlcdclose.html @ 688:c0522010bb6d
Date: Tue, 12 Aug 2003 14:26:19 +0200 (MEST)
From: "Mattias Engdeg?rd"
Subject: bug in SDL_GetRGB/GetRGBA
There's an embarrassing bug in GetRGB/GetRGBA which apparently has been there
for years. It incorrectly converts colours with < 8 bits/channel.
It came to my attention today in #sdl.
What it does now is (for each channel):
rv = (pixel & fmt->Rmask) >> fmt->Rshift;
*r = (rv << fmt->Rloss) + (rv >> (8 - fmt->Rloss));
which is wrong; the last line should be
*r = (rv << fmt->Rloss) + (rv >> (8 - (fmt->Rloss << 1)));
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Tue, 12 Aug 2003 15:17:20 +0000 |
| parents | e5bc29de3f0a |
| children | 355632dca928 |
| rev | line source |
|---|---|
| 0 | 1 <HTML |
| 2 ><HEAD | |
| 3 ><TITLE | |
| 4 >SDL_CDClose</TITLE | |
| 5 ><META | |
| 6 NAME="GENERATOR" | |
|
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|
7 CONTENT="Modular DocBook HTML Stylesheet Version 1.64 |
| 0 | 8 "><LINK |
| 9 REL="HOME" | |
| 10 TITLE="SDL Library Documentation" | |
| 11 HREF="index.html"><LINK | |
| 12 REL="UP" | |
| 13 TITLE="CD-ROM" | |
| 14 HREF="cdrom.html"><LINK | |
| 15 REL="PREVIOUS" | |
| 16 TITLE="SDL_CDEject" | |
| 17 HREF="sdlcdeject.html"><LINK | |
| 18 REL="NEXT" | |
| 19 TITLE="SDL_CD" | |
| 20 HREF="sdlcd.html"></HEAD | |
| 21 ><BODY | |
| 22 CLASS="REFENTRY" | |
| 23 BGCOLOR="#FFF8DC" | |
| 24 TEXT="#000000" | |
| 25 LINK="#0000ee" | |
| 26 VLINK="#551a8b" | |
| 27 ALINK="#ff0000" | |
| 28 ><DIV | |
| 29 CLASS="NAVHEADER" | |
| 30 ><TABLE | |
| 31 WIDTH="100%" | |
| 32 BORDER="0" | |
| 33 CELLPADDING="0" | |
| 34 CELLSPACING="0" | |
| 35 ><TR | |
| 36 ><TH | |
| 37 COLSPAN="3" | |
| 38 ALIGN="center" | |
| 39 >SDL Library Documentation</TH | |
| 40 ></TR | |
| 41 ><TR | |
| 42 ><TD | |
| 43 WIDTH="10%" | |
| 44 ALIGN="left" | |
| 45 VALIGN="bottom" | |
| 46 ><A | |
| 47 HREF="sdlcdeject.html" | |
| 48 >Prev</A | |
| 49 ></TD | |
| 50 ><TD | |
| 51 WIDTH="80%" | |
| 52 ALIGN="center" | |
| 53 VALIGN="bottom" | |
| 54 ></TD | |
| 55 ><TD | |
| 56 WIDTH="10%" | |
| 57 ALIGN="right" | |
| 58 VALIGN="bottom" | |
| 59 ><A | |
| 60 HREF="sdlcd.html" | |
| 61 >Next</A | |
| 62 ></TD | |
| 63 ></TR | |
| 64 ></TABLE | |
| 65 ><HR | |
| 66 ALIGN="LEFT" | |
| 67 WIDTH="100%"></DIV | |
| 68 ><H1 | |
| 69 ><A | |
| 70 NAME="SDLCDCLOSE" | |
| 71 >SDL_CDClose</A | |
| 72 ></H1 | |
| 73 ><DIV | |
| 74 CLASS="REFNAMEDIV" | |
| 75 ><A | |
|
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76 NAME="AEN7153" |
| 0 | 77 ></A |
| 78 ><H2 | |
| 79 >Name</H2 | |
| 80 >SDL_CDClose -- Closes a SDL_CD handle</DIV | |
| 81 ><DIV | |
| 82 CLASS="REFSYNOPSISDIV" | |
| 83 ><A | |
|
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84 NAME="AEN7156" |
| 0 | 85 ></A |
| 86 ><H2 | |
| 87 >Synopsis</H2 | |
| 88 ><DIV | |
| 89 CLASS="FUNCSYNOPSIS" | |
| 90 ><A | |
|
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91 NAME="AEN7157" |
| 0 | 92 ></A |
| 93 ><P | |
| 94 ></P | |
| 95 ><PRE | |
| 96 CLASS="FUNCSYNOPSISINFO" | |
| 97 >#include "SDL.h"</PRE | |
| 98 ><P | |
| 99 ><CODE | |
| 100 ><CODE | |
| 101 CLASS="FUNCDEF" | |
| 102 >void <B | |
| 103 CLASS="FSFUNC" | |
| 104 >SDL_CDClose</B | |
| 105 ></CODE | |
| 106 >(SDL_CD *cdrom);</CODE | |
| 107 ></P | |
| 108 ><P | |
| 109 ></P | |
| 110 ></DIV | |
| 111 ></DIV | |
| 112 ><DIV | |
| 113 CLASS="REFSECT1" | |
| 114 ><A | |
|
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115 NAME="AEN7163" |
| 0 | 116 ></A |
| 117 ><H2 | |
| 118 >Description</H2 | |
| 119 ><P | |
| 120 >Closes the given <TT | |
| 121 CLASS="PARAMETER" | |
| 122 ><I | |
| 123 >cdrom</I | |
| 124 ></TT | |
| 125 > handle.</P | |
| 126 ></DIV | |
| 127 ><DIV | |
| 128 CLASS="REFSECT1" | |
| 129 ><A | |
|
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130 NAME="AEN7167" |
| 0 | 131 ></A |
| 132 ><H2 | |
| 133 >See Also</H2 | |
| 134 ><P | |
| 135 ><A | |
| 136 HREF="sdlcdopen.html" | |
| 137 ><TT | |
| 138 CLASS="FUNCTION" | |
| 139 >SDL_CDOpen</TT | |
| 140 ></A | |
| 141 >, | |
| 142 <A | |
| 143 HREF="sdlcd.html" | |
| 144 ><SPAN | |
| 145 CLASS="STRUCTNAME" | |
| 146 >SDL_CD</SPAN | |
| 147 ></A | |
| 148 ></P | |
| 149 ></DIV | |
| 150 ><DIV | |
| 151 CLASS="NAVFOOTER" | |
| 152 ><HR | |
| 153 ALIGN="LEFT" | |
| 154 WIDTH="100%"><TABLE | |
| 155 WIDTH="100%" | |
| 156 BORDER="0" | |
| 157 CELLPADDING="0" | |
| 158 CELLSPACING="0" | |
| 159 ><TR | |
| 160 ><TD | |
| 161 WIDTH="33%" | |
| 162 ALIGN="left" | |
| 163 VALIGN="top" | |
| 164 ><A | |
| 165 HREF="sdlcdeject.html" | |
| 166 >Prev</A | |
| 167 ></TD | |
| 168 ><TD | |
| 169 WIDTH="34%" | |
| 170 ALIGN="center" | |
| 171 VALIGN="top" | |
| 172 ><A | |
| 173 HREF="index.html" | |
| 174 >Home</A | |
| 175 ></TD | |
| 176 ><TD | |
| 177 WIDTH="33%" | |
| 178 ALIGN="right" | |
| 179 VALIGN="top" | |
| 180 ><A | |
| 181 HREF="sdlcd.html" | |
| 182 >Next</A | |
| 183 ></TD | |
| 184 ></TR | |
| 185 ><TR | |
| 186 ><TD | |
| 187 WIDTH="33%" | |
| 188 ALIGN="left" | |
| 189 VALIGN="top" | |
| 190 >SDL_CDEject</TD | |
| 191 ><TD | |
| 192 WIDTH="34%" | |
| 193 ALIGN="center" | |
| 194 VALIGN="top" | |
| 195 ><A | |
| 196 HREF="cdrom.html" | |
| 197 >Up</A | |
| 198 ></TD | |
| 199 ><TD | |
| 200 WIDTH="33%" | |
| 201 ALIGN="right" | |
| 202 VALIGN="top" | |
| 203 >SDL_CD</TD | |
| 204 ></TR | |
| 205 ></TABLE | |
| 206 ></DIV | |
| 207 ></BODY | |
| 208 ></HTML | |
| 209 > |