Mercurial > sdl-ios-xcode
annotate docs/html/sdlglgetprocaddress.html @ 883:50f5a29c6a17
Date: Sat, 10 Apr 2004 02:25:33 -0400
From: Glenn Maynard
To: sdl@libsdl.org
Subject: [SDL] SDL_SetVideoMode() failing and not setting an error (patch)
Running an OpenGL SDL application off 1.2.7, at SDL_InitSubSystem(SDL_INIT_VIDEO) time:
Warning: Unable to initialize AAlib mouseUsing AAlib driver: Slang driver 1.0 (slang)
SDL_SetVideoMode then fails; SDL_GetError() returns "".
The installation problem is straightforward: X (the higher priority
driver) isn't running, so SDL is falling back on aalib. However,
no error is being set when aalib fails to initialize. This also
happens with the svgalib driver.
SDL_video.c line ~653 sets mode to NULL, since aalib didn't return an
OpenGL surface. Line ~711 ("failed setting a video mode") returns NULL.
The attached patch sets an error. It's a horrible, useless error
message--it should really say eg. "aalib does not support OpenGL"; this
should probably be done earlier in the individual drivers, too.
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Sun, 11 Apr 2004 19:54:40 +0000 |
| parents | 355632dca928 |
| children |
| rev | line source |
|---|---|
| 0 | 1 <HTML |
| 2 ><HEAD | |
| 3 ><TITLE | |
| 4 >SDL_GL_GetProcAddress</TITLE | |
| 5 ><META | |
| 6 NAME="GENERATOR" | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
7 CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+ |
| 0 | 8 "><LINK |
| 9 REL="HOME" | |
| 10 TITLE="SDL Library Documentation" | |
| 11 HREF="index.html"><LINK | |
| 12 REL="UP" | |
| 13 TITLE="Video" | |
| 14 HREF="video.html"><LINK | |
| 15 REL="PREVIOUS" | |
| 16 TITLE="SDL_GL_LoadLibrary" | |
| 17 HREF="sdlglloadlibrary.html"><LINK | |
| 18 REL="NEXT" | |
| 19 TITLE="SDL_GL_GetAttribute" | |
| 20 HREF="sdlglgetattribute.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 | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
31 SUMMARY="Header navigation table" |
| 0 | 32 WIDTH="100%" |
| 33 BORDER="0" | |
| 34 CELLPADDING="0" | |
| 35 CELLSPACING="0" | |
| 36 ><TR | |
| 37 ><TH | |
| 38 COLSPAN="3" | |
| 39 ALIGN="center" | |
| 40 >SDL Library Documentation</TH | |
| 41 ></TR | |
| 42 ><TR | |
| 43 ><TD | |
| 44 WIDTH="10%" | |
| 45 ALIGN="left" | |
| 46 VALIGN="bottom" | |
| 47 ><A | |
| 48 HREF="sdlglloadlibrary.html" | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
49 ACCESSKEY="P" |
| 0 | 50 >Prev</A |
| 51 ></TD | |
| 52 ><TD | |
| 53 WIDTH="80%" | |
| 54 ALIGN="center" | |
| 55 VALIGN="bottom" | |
| 56 ></TD | |
| 57 ><TD | |
| 58 WIDTH="10%" | |
| 59 ALIGN="right" | |
| 60 VALIGN="bottom" | |
| 61 ><A | |
| 62 HREF="sdlglgetattribute.html" | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
63 ACCESSKEY="N" |
| 0 | 64 >Next</A |
| 65 ></TD | |
| 66 ></TR | |
| 67 ></TABLE | |
| 68 ><HR | |
| 69 ALIGN="LEFT" | |
| 70 WIDTH="100%"></DIV | |
| 71 ><H1 | |
| 72 ><A | |
| 73 NAME="SDLGLGETPROCADDRESS" | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
74 ></A |
|
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
75 >SDL_GL_GetProcAddress</H1 |
| 0 | 76 ><DIV |
| 77 CLASS="REFNAMEDIV" | |
| 78 ><A | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
79 NAME="AEN2678" |
| 0 | 80 ></A |
| 81 ><H2 | |
| 82 >Name</H2 | |
| 83 >SDL_GL_GetProcAddress -- Get the address of a GL function</DIV | |
| 84 ><DIV | |
| 85 CLASS="REFSYNOPSISDIV" | |
| 86 ><A | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
87 NAME="AEN2681" |
| 0 | 88 ></A |
| 89 ><H2 | |
| 90 >Synopsis</H2 | |
| 91 ><DIV | |
| 92 CLASS="FUNCSYNOPSIS" | |
| 93 ><A | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
94 NAME="AEN2682" |
| 0 | 95 ></A |
| 96 ><P | |
| 97 ></P | |
| 98 ><PRE | |
| 99 CLASS="FUNCSYNOPSISINFO" | |
| 100 >#include "SDL.h"</PRE | |
| 101 ><P | |
| 102 ><CODE | |
| 103 ><CODE | |
| 104 CLASS="FUNCDEF" | |
| 105 >void *<B | |
| 106 CLASS="FSFUNC" | |
| 107 >SDL_GL_GetProcAddress</B | |
| 108 ></CODE | |
| 109 >(const char* proc);</CODE | |
| 110 ></P | |
| 111 ><P | |
| 112 ></P | |
| 113 ></DIV | |
| 114 ></DIV | |
| 115 ><DIV | |
| 116 CLASS="REFSECT1" | |
| 117 ><A | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
118 NAME="AEN2688" |
| 0 | 119 ></A |
| 120 ><H2 | |
| 121 >Description</H2 | |
| 122 ><P | |
| 123 >Returns the address of the GL function <TT | |
| 124 CLASS="PARAMETER" | |
| 125 ><I | |
| 126 >proc</I | |
| 127 ></TT | |
| 128 >, or <SPAN | |
| 129 CLASS="RETURNVALUE" | |
| 130 >NULL</SPAN | |
| 131 > if the function is not found. If the GL library is loaded at runtime, with <A | |
| 132 HREF="sdlglloadlibrary.html" | |
| 133 ><TT | |
| 134 CLASS="FUNCTION" | |
| 135 >SDL_GL_LoadLibrary</TT | |
| 136 ></A | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
137 >, then <SPAN |
|
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
138 CLASS="emphasis" |
|
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
139 ><I |
| 0 | 140 CLASS="EMPHASIS" |
| 141 >all</I | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
142 ></SPAN |
| 0 | 143 > GL functions must be retrieved this way. Usually this is used to retrieve function pointers to OpenGL extensions.</P |
| 144 ></DIV | |
| 145 ><DIV | |
| 146 CLASS="REFSECT1" | |
| 147 ><A | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
148 NAME="AEN2696" |
| 0 | 149 ></A |
| 150 ><H2 | |
| 151 >Example</H2 | |
| 152 ><PRE | |
| 153 CLASS="PROGRAMLISTING" | |
| 154 >typedef void (*GL_ActiveTextureARB_Func)(unsigned int); | |
| 155 GL_ActiveTextureARB_Func glActiveTextureARB_ptr = 0; | |
| 156 int has_multitexture=1; | |
| 157 . | |
| 158 . | |
| 159 . | |
| 160 /* Get function pointer */ | |
| 161 glActiveTextureARB_ptr=(GL_ActiveTextureARB_Func) SDL_GL_GetProcAddress("glActiveTextureARB"); | |
| 162 | |
| 163 /* Check for a valid function ptr */ | |
| 164 if(!glActiveTextureARB_ptr){ | |
| 165 fprintf(stderr, "Multitexture Extensions not present.\n"); | |
| 166 has_multitexture=0; | |
| 167 } | |
| 168 . | |
| 169 . | |
| 170 . | |
| 171 . | |
| 172 if(has_multitexture){ | |
| 173 glActiveTextureARB_ptr(GL_TEXTURE0_ARB); | |
| 174 . | |
| 175 . | |
| 176 } | |
| 177 else{ | |
| 178 . | |
| 179 . | |
| 180 }</PRE | |
| 181 ></DIV | |
| 182 ><DIV | |
| 183 CLASS="REFSECT1" | |
| 184 ><A | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
185 NAME="AEN2699" |
| 0 | 186 ></A |
| 187 ><H2 | |
| 188 >See Also</H2 | |
| 189 ><P | |
| 190 ><A | |
| 191 HREF="sdlglloadlibrary.html" | |
| 192 ><TT | |
| 193 CLASS="FUNCTION" | |
| 194 >SDL_GL_LoadLibrary</TT | |
| 195 ></A | |
| 196 ></P | |
| 197 ></DIV | |
| 198 ><DIV | |
| 199 CLASS="NAVFOOTER" | |
| 200 ><HR | |
| 201 ALIGN="LEFT" | |
| 202 WIDTH="100%"><TABLE | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
203 SUMMARY="Footer navigation table" |
| 0 | 204 WIDTH="100%" |
| 205 BORDER="0" | |
| 206 CELLPADDING="0" | |
| 207 CELLSPACING="0" | |
| 208 ><TR | |
| 209 ><TD | |
| 210 WIDTH="33%" | |
| 211 ALIGN="left" | |
| 212 VALIGN="top" | |
| 213 ><A | |
| 214 HREF="sdlglloadlibrary.html" | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
215 ACCESSKEY="P" |
| 0 | 216 >Prev</A |
| 217 ></TD | |
| 218 ><TD | |
| 219 WIDTH="34%" | |
| 220 ALIGN="center" | |
| 221 VALIGN="top" | |
| 222 ><A | |
| 223 HREF="index.html" | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
224 ACCESSKEY="H" |
| 0 | 225 >Home</A |
| 226 ></TD | |
| 227 ><TD | |
| 228 WIDTH="33%" | |
| 229 ALIGN="right" | |
| 230 VALIGN="top" | |
| 231 ><A | |
| 232 HREF="sdlglgetattribute.html" | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
233 ACCESSKEY="N" |
| 0 | 234 >Next</A |
| 235 ></TD | |
| 236 ></TR | |
| 237 ><TR | |
| 238 ><TD | |
| 239 WIDTH="33%" | |
| 240 ALIGN="left" | |
| 241 VALIGN="top" | |
| 242 >SDL_GL_LoadLibrary</TD | |
| 243 ><TD | |
| 244 WIDTH="34%" | |
| 245 ALIGN="center" | |
| 246 VALIGN="top" | |
| 247 ><A | |
| 248 HREF="video.html" | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
249 ACCESSKEY="U" |
| 0 | 250 >Up</A |
| 251 ></TD | |
| 252 ><TD | |
| 253 WIDTH="33%" | |
| 254 ALIGN="right" | |
| 255 VALIGN="top" | |
| 256 >SDL_GL_GetAttribute</TD | |
| 257 ></TR | |
| 258 ></TABLE | |
| 259 ></DIV | |
| 260 ></BODY | |
| 261 ></HTML | |
| 262 > |