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diff --git a/doc/basic.html b/doc/basic.html new file mode 100644 index 0000000..038a155 --- /dev/null +++ b/doc/basic.html @@ -0,0 +1,278 @@ +<!-- begin header.html --> +<!-- +The OpenGL Extension Wrangler Library +Copyright (C) 2008-2015, Nigel Stewart <nigels[]users sourceforge net> +Copyright (C) 2002-2008, Milan Ikits <milan ikits[]ieee org> +Copyright (C) 2002-2008, Marcelo E. Magallon <mmagallo[]debian org> +Copyright (C) 2002, Lev Povalahev +All rights reserved. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are met: + +* Redistributions of source code must retain the above copyright notice, + this list of conditions and the following disclaimer. +* Redistributions in binary form must reproduce the above copyright notice, + this list of conditions and the following disclaimer in the documentation + and/or other materials provided with the distribution. +* The name of the author may be used to endorse or promote products + derived from this software without specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" +AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE +LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR +CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF +SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS +INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN +CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) +ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF +THE POSSIBILITY OF SUCH DAMAGE. +--> +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html/4/loose.dtd"> +<html> +<head> +<title>GLEW: The OpenGL Extension Wrangler Library</title> +<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> +<link href="glew.css" type="text/css" rel="stylesheet"> +</head> +<body bgcolor="#fff0d0"> +<table border="0" width="100%" cellpadding="12" cellspacing="8" style="height:100%"> +<tr> +<td bgcolor="#ffffff" align="left" valign="top" width="200"> +<table border="0" width="100%" cellpadding="0" cellspacing="0" align="left"> +<tr> +<td valign="top"> + +<table border="0" width="100%" cellpadding="0" cellspacing="0" align="left"> +<tr><td align="center"><i>Latest Release: <a href="https://sourceforge.net/projects/glew/files/glew/1.13.0/">1.13.0</a></i></td></tr> +<tr><td align="center"><br></td></tr> +<tr><td align="center"><img src="./glew.png" alt="GLEW Logo" width="97" height="75"></td></tr> +<tr><td align="center"><br></td></tr> +<tr><td align="center"> +<table border="0" cellpadding="0" cellspacing="0" align="center"> +<tr><td align="center"><a href="index.html">Download</a></td></tr> +<tr><td align="center">Usage</td></tr> +<tr><td align="center"><a href="build.html">Building</a></td></tr> +<tr><td align="center"><a href="install.html">Installation</a></td></tr> +<tr><td align="center"><a href="advanced.html">Source Generation</a></td></tr> +<tr><td align="center"><a href="credits.html">Credits & Copyright</a></td></tr> +<tr><td align="center"><a href="log.html">Change Log</a></td></tr> +<tr></tr> +<tr><td align="center"><a href="https://github.com/nigels-com/glew">GitHub</a></td></tr> +<tr><td align="center"><a href="https://sourceforge.net/projects/glew">Project Page</a></td></tr> +<tr><td align="center"><a href="http://sourceforge.net/p/glew/bugs/">Bug Tracker</a></td></tr> +</table> +<tr><td align="center"><br></tr> +</table> +</td> +</tr> +<tr> + +<td valign="bottom"> +<table border="0" width="100%" cellpadding="5" cellspacing="0" align="left"> +<tr><td align="center"><i>Last Update: 08-10-15</i></td></tr> +<tr><td align="center"> + <a href="http://www.opengl.org"><img src="./ogl_sm.jpg" width="68" height="35" border="0" alt="OpenGL Logo"></a><br/> + <a href="https://github.com/nigels-com/glew"><img src="github.png" width="70" height="29" border="0" alt="GitHub Logo"></a><br/> + <a href="http://sourceforge.net"><img src="http://sourceforge.net/sflogo.php?group_id=67586&type=1" width="88" height="31" border="0" alt="SourceForge Logo"></a> +</td> +</tr> +</table> +</td> +</tr> +</table> +</td> + +<td bgcolor="#ffffff" align="left" valign="top"> + +<h1>The OpenGL Extension Wrangler Library</h1> + +<!-- end header.html --> + + +<h2>Initializing GLEW</h2> +<p> +First you need to create a valid OpenGL rendering context and call +<tt>glewInit()</tt> to initialize the extension entry points. If +<tt>glewInit()</tt> returns <tt>GLEW_OK</tt>, the initialization +succeeded and you can use the available extensions as well as core +OpenGL functionality. For example: +</p> + +<p class="pre"> +#include <GL/glew.h><br> +#include <GL/glut.h><br> +...<br> +glutInit(&argc, argv);<br> +glutCreateWindow("GLEW Test");<br> +GLenum err = glewInit();<br> +if (GLEW_OK != err)<br> +{<br> + /* Problem: glewInit failed, something is seriously wrong. */<br> + fprintf(stderr, "Error: %s\n", glewGetErrorString(err));<br> + ...<br> +}<br> +fprintf(stdout, "Status: Using GLEW %s\n", glewGetString(GLEW_VERSION));<br> +</p> + +<h2>Checking for Extensions</h2> + +<p> +Starting from GLEW 1.1.0, you can find out if a particular extension +is available on your platform by querying globally defined variables +of the form <tt>GLEW_{extension_name}</tt>: +</p> + +<p class="pre"> +if (GLEW_ARB_vertex_program)<br> +{<br> + /* It is safe to use the ARB_vertex_program extension here. */<br> + glGenProgramsARB(...);<br> +}<br> +</p> + +<p> +<b>In GLEW 1.0.x, a global structure was used for this task. To ensure +binary compatibility between releases, the struct was replaced with a +set of variables.</b> +</p> + +<p> +You can also check for core OpenGL functionality. For example, to +see if OpenGL 1.3 is supported, do the following: +</p> + +<p class="pre"> +if (GLEW_VERSION_1_3)<br> +{<br> + /* Yay! OpenGL 1.3 is supported! */<br> +}<br> +</p> + +<p> +In general, you can check if <tt>GLEW_{extension_name}</tt> or +<tt>GLEW_VERSION_{version}</tt> is true or false. +</p> + +<p> +It is also possible to perform extension checks from string +input. Starting from the 1.3.0 release, use <tt>glewIsSupported</tt> +to check if the required core or extension functionality is +available: +</p> + +<p class="pre"> +if (glewIsSupported("GL_VERSION_1_4 GL_ARB_point_sprite"))<br> +{<br> + /* Great, we have OpenGL 1.4 + point sprites. */<br> +}<br> +</p> + +<p> +For extensions only, <tt>glewGetExtension</tt> provides a slower alternative +(GLEW 1.0.x-1.2.x). <b>Note that in the 1.3.0 release </b> +<tt>glewGetExtension</tt> <b>was replaced with </b> +<tt>glewIsSupported</tt>. +</p> + +<p class="pre"> +if (glewGetExtension("GL_ARB_fragment_program"))<br> +{<br> + /* Looks like ARB_fragment_program is supported. */<br> +}<br> +</p> + +<h2>Experimental Drivers</h2> + +<p> +GLEW obtains information on the supported extensions from the graphics +driver. Experimental or pre-release drivers, however, might not +report every available extension through the standard mechanism, in +which case GLEW will report it unsupported. To circumvent this +situation, the <tt>glewExperimental</tt> global switch can be turned +on by setting it to <tt>GL_TRUE</tt> before calling +<tt>glewInit()</tt>, which ensures that all extensions with valid +entry points will be exposed. +</p> + +<h2>Platform Specific Extensions</h2> + +<p> +Platform specific extensions are separated into two header files: +<tt>wglew.h</tt> and <tt>glxew.h</tt>, which define the available +<tt>WGL</tt> and <tt>GLX</tt> extensions. To determine if a certain +extension is supported, query <tt>WGLEW_{extension name}</tt> or +<tt>GLXEW_{extension_name}</tt>. For example: +</p> + +<p class="pre"> +#include <GL/wglew.h><br> +<br> +if (WGLEW_ARB_pbuffer)<br> +{<br> + /* OK, we can use pbuffers. */<br> +}<br> +else<br> +{<br> + /* Sorry, pbuffers will not work on this platform. */<br> +}<br> +</p> + +<p> +Alternatively, use <tt>wglewIsSupported</tt> or +<tt>glxewIsSupported</tt> to check for extensions from a string: +</p> + +<p class="pre"> +if (wglewIsSupported("WGL_ARB_pbuffer"))<br> +{<br> + /* OK, we can use pbuffers. */<br> +}<br> +</p> + +<h2>Utilities</h2> + +<p> +GLEW provides two command-line utilities: one for creating a list of +available extensions and visuals; and another for verifying extension +entry points. +</p> + +<h3>visualinfo: extensions and visuals</h3> + +<p> +<tt>visualinfo</tt> is an extended version of <tt>glxinfo</tt>. The +Windows version creates a file called <tt>visualinfo.txt</tt>, which +contains a list of available OpenGL, WGL, and GLU extensions as well +as a table of visuals aka. pixel formats. Pbuffer and MRT capable +visuals are also included. For additional usage information, type +<tt>visualinfo -h</tt>. +</p> + +<h3>glewinfo: extension verification utility</h3> + +<p> +<tt>glewinfo</tt> allows you to verify the entry points for the +extensions supported on your platform. The Windows version +reports the results to a text file called <tt>glewinfo.txt</tt>. The +Unix version prints the results to <tt>stdout</tt>. +</p> + +<p>Windows usage:</p> + <blockquote><pre>glewinfo [-pf <id>]</pre></blockquote> + +<p>where <tt><id></tt> is the pixel format id for which the +capabilities are displayed.</p> + +<p>Unix usage:</p> +<blockquote><pre>glewinfo [-display <dpy>] [-visual <id>]</pre></blockquote> + +<p>where <tt><dpy></tt> is the X11 display and <tt><id></tt> is +the visual id for which the capabilities are displayed.</p> + +<!-- begin footer.html --> +</td></tr></table></body> +<!-- end footer.html --> + |