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<h1 style="text-align:center">
OpenGL&reg; Application Binary Interface for Linux <br/>
<span style="font-size:12px"> (formerly Linux/OpenGL Base) </span>
<p style="text-align:center">Version 1.0<br/>
Approved June 20, 2000<br/>
Editor: Jon Leech, SGI </p>
<h6>Latest News</h6>
<p> Version 1.0 is complete. It was approved on June 20, 2000; all
submitted votes were in favor. </p>
<li><a href="#1">1. Overview and Goals </a></li>
<li><a href="#2">2. Calling Conventions</a></li>
<li><a href="#3">3. Libraries</a></li>
<li><a href="#4">4. Header Files</a></li>
<li><a href="#5">5. Extension Headers</a></li>
<li><a href="#6">6. Feedback and Mailing Lists</a></li>
<li><a href="#app">Appendix: Open Issues</a></li>
<li><a href="#log">Change Log</a></li>
<p> <a name="1"></a></p>
<h6>1. Overview and Goals </h6>
<p> 1.1. This document is intended to solve two related problems. First,
defining the ABI and runtime environment for applications using
OpenGL under X11 on Linux. This will enable applications using the
OpenGL API for rendering to run on a variety of underlying
implementations transparently. The intent is to address all of open
source, commercial closed binary, OpenGL SI-based, and Mesa-based
implementations. </p>
<p> Second, defining the SDK for developing apps using OpenGL. This
includes header file locations, conventions for use of extensions,
etc. </p>
<p> It has similar goals to the <a href="">Linux
Standard Base</a>, but focused much
more narrowly: on the OpenGL API. Representatives from LSB are
involved and ultimately this effort should be part of LSB. </p>
<p> We do not exactly track all LSB practice (particularly naming
conventions for libraries) because LSB itself is not complete, and
because existing practice with other OpenGL implementations suggests
preferred methods which may differ from LSB. </p>
<p> 1.2. Things we do <b>not</b> attempt to address include: </p>
<li> Internal implementation dependent issues - details of direct
rendering, loadable driver modules, etc. Such details are
hidden from the public interfaces by the implementation,
and are irrelevant to applications using the ABI. </li>
<li> Operating systems other than Linux. Other platforms such as BSD
are welcome to use whatever comes out of this project, but we
are explicitly not trying to solve this problem for every free
OS in the world. </li>
<li> Changes to the OpenGL API. The definition of OpenGL is
controlled by the OpenGL Architecture Review Board, and we in no
way challenge this. A single GLX extension is required; this
extension has already been approved by the ARB. </li>
<li> Use of 3D outside the X11/GLX context. There are a variety of
approaches (fxMesa, GGI, etc.) that again are welcome to use
relevant parts of this project, but whose support is not part of
its goals. </li>
<p> 1.3. We believe all critical decisions have been made. Some
remaining comments (previously identified as open issues) of
interest are identified in the <a href="#app">appendix</a>. We
recognize that some decisions are largely arbitrary (filenames and
file locations, for example) and in those cases have been guided by
existing practice (<i>in other words, complaining about arbitrary
decisions is unlikely to change them</i>). </p>
<p> 1.4. Participants in this effort to date include people working at
or involved with the following companies and open source projects
(as well as a large number of individuals with unknown
affiliations): </p>
3Dfx, Alias/Wavefront, Apple, Avid, Compaq, Debian, HP, IBM, Intel,
Linux Standard Base, Loki Games, Mesa, Metro Link, NVIDIA, Nichimen,
Parametric Technology Corporation, Precision Insight, SGI, Sharp
Eye, Sun, XFree86, Xi Graphics.</blockquote>
<p> <a name="2"></a></p>
<h6>2. Calling Conventions</h6>
<p> 2.1. OpenGL already includes its own datatypes (<tt>GLint,
GLshort,</tt> etc.) used in the API. Guaranteed minimum sizes are
stated (see table 2.2 of the OpenGL 1.2 Specification), but the
actual choice of C datatype is left to the implementation. For our
purposes, however, all implementations on a given binary
architecture must have common definitions of these datatypes. </p>
<p> For the IA32 architecture, the definitions should be: </p>
<table border="1" class="center-table">
<tr><td>GL datatype</td>
<td>gcc equivalent for IA32</td></tr>
<td>8-bit boolean</td>
<td><tt>unsigned char</tt></td></tr>
<td>signed 8-bit 2's-complement integer</td>
<td><tt>signed char</tt></td></tr>
<td>unsigned 8-bit integer</td>
<td><tt>unsigned char</tt></td></tr>
<td>signed 16-bit 2's-complement integer</td>
<td>unsigned 16-bit integer</td>
<td><tt>unsigned short</tt></td></tr>
<td>signed 32-bit 2's-complement integer</td>
<td>unsigned 32-bit integer</td>
<td><tt>unsigned int</tt></td></tr>
<td>non-negative 32-bit binary integer size</td>
<td>enumerated 32-bit value</td>
<td><tt>unsigned int</tt></td></tr>
<td>32 bit bitfield</td>
<td><tt>unsigned int</tt></td></tr>
<td>32-bit IEEE754 floating-point</td>
<td>Same as GLfloat, but in range [0, 1]</td>
<td>64-bit IEEE754 floating-point</td>
<td>Same as GLdouble, but in range [0, 1]</td>
<p> <a href="#issue2.1">Issues</a></p>
<p> 2.2. Assembly-level call conventions must be shared. Since the
OpenGL implementation may use C++ code internally (e.g. for GLU),
this is potentially a serious problem. Static linking of C++
libraries used by OpenGL libraries may be required of the
implementation (also see the <a href="#3">Libraries</a> section
below). </p>
<p> <a href="#issue2.2">Issues</a> </p>
<p> <a name="3"></a></p>
<h6>3. Libraries</h6>
<p> 3.1. There are two link-level libraries. <tt>libGL</tt> includes the
OpenGL and GLX entry points and in general depends on underlying
hardware and/or X server dependent code that may or may not be
incorporated into this library. <tt>libGLU</tt> includes the GLU
utility routines and should be hardware independent, using only the
OpenGL API. </p>
<p> Each library has two names: the link name used
on the ld command line, and the <tt>DT_SONAME</tt> within that
library (specified by the <i>-soname</i> switch when linking the
library), defining where it's looked up at runtime. Both forms must
exist so that both linking and running will operate properly. The
library names are: </p>
<table cellspacing="1" border="1" class="center-table">
<tr><td>Link name</td>
<td>Runtime name (<tt>DT_SONAME</tt>)</td>
<p> <tt></tt> and <tt></tt> should
be symbolic links pointing to the runtime names, so that
future versions of the standard can be implemented transparently
to applications by changing the link. </p>
<p> <a href="#issue3.1">Issues</a> </p>
<p> 3.2. These libraries must be located in <tt>/usr/lib</tt>. The
X-specific library direction (<tt>/usr/lib/X11</tt>) was also
considered, but existing practice on Linux and other platforms
indicates that <tt>/usr/lib</tt> is preferable. </p>
<p> <a href="#issue3.2">Issues</a>
<p> 3.3. C++ runtime environments are likely to be incompatible
cross-platform, including both the standard C++ library location and
entry points, and the semantics of issues such as static
constructors and destructors. The LSB apparently mandates static
linking of libraries which aren't already in LSB, but this could
lead to problems with multiple C++ RTLs present in the same app
using C++. We'll have to tread carefully here until this issue
is more completely understood. </p>
<p> <a href="#issue3.3">Issues</a> </p>
<p> 3.4. The libraries must export all OpenGL 1.2,
GLU 1.3, GLX 1.3, and <tt>ARB_multitexture</tt> entry points
statically. </p>
<p> It's possible (but unlikely) that additional ARB or vendor
extensions will be mandated before the ABI is finalized.
Applications should not expect to link statically against any entry
points not specified here. </p>
<p> 3.5. Because non-ARB extensions vary so widely and are constantly
increasing in number, it's infeasible to require that they all be
supported, and extensions can always be added to hardware drivers
after the base link libraries are released. These drivers are
dynamically loaded by <tt>libGL</tt>, so extensions not in the base
library must also be obtained dynamically. </p>
<p> 3.6. To perform the dynamic query,
<tt>libGL</tt> also must export an entry point called </p>
<tt>void (*glXGetProcAddressARB(const GLubyte *))();</tt>
<p> The <a href="">full specification</a>
of this function is available separately. It takes the string name
of a GL or GLX entry point and returns a pointer to a function
implementing that entry point. It is functionally identical to the
<tt>wglGetProcAddress</tt> query defined by the Windows OpenGL
library, except that the function pointers returned are <i>context
independent</i>, unlike the WGL query. </p>
<p> All OpenGL and GLX entry points may be queried with this extension;
GLU extensions cannot, because GLU is a client-side library that
cannot easily be extended. </p>
<p> <a href="#issue3.6">Issues</a> </p>
<p> 3.7. Thread safety (the ability to issue OpenGL calls to different
graphics contexts from different application threads) is required.
Multithreaded applications must use <b>-lpthread</b>. </p>
<p> 3.8. <tt>libGL</tt> and <tt>libGLU</tt> must be
transitively linked with any libraries they require in their own
internal implementation, so that applications don't fail on some
implementations due to not pulling in libraries needed not by the
app, but by the implementation. </p>
<p> <a name="4"></a></p>
<h6>4. Header Files</h6>
<p> 4.1. The following header files are required: </p>
<li> <tt>&lt;GL/gl.h&gt;</tt> - OpenGL </li>
<li> <tt>&lt;GL/glx.h&gt;</tt> - GLX </li>
<li> <tt>&lt;GL/glu.h&gt;</tt> - GLU </li>
<li> <tt>&lt;GL/glext.h&gt;</tt> - OpenGL Extensions </li>
<li> <tt>&lt;GL/glxext.h&gt;</tt> - GLX Extensions </li>
<p> These headers should properly define prototypes and enumerants for
use by applications written in either C or C++. Other language
bindings are not addressed at this time. </p>
<p> 4.2. These header files must be located in <tt>/usr/include/GL</tt>.
<tt>/usr/include/X11/GL</tt> was considered and rejected for the
same reasons as library locations in section 3.2 above. </p>
<p> 4.3. The required headers must not pull in
internal headers or headers from other packages where that would
cause unexpected namespace pollution (for example, on IRIX
<tt>glx.h</tt> pulls in <tt>&lt;X11/Xmd.h&gt;</tt>). Likewise the
required headers must be protected against multiple inclusion and
should not themselves include any headers that are not so protected.
However, <tt>glx.h</tt> is allowed to include
<tt>&lt;X11/Xlib.h&gt;</tt> and <tt>&lt;X11/Xutil.h&gt;</tt>. </p>
<p> 4.4. <tt>glx.h</tt> must include the prototype of the
<tt>glXGetProcAddressARB</tt> extension described above. </p>
<p> 4.5. All OpenGL 1.2 and <tt>ARB_multitexture</tt>, GLU 1.3, and GLX
1.3 entry points and enumerants must be present in the corresponding
header files <tt>gl.h</tt>, <tt>glu.h</tt>, and <tt>glx.h</tt>,
<b>even if</b> only OpenGL 1.1 is implemented at runtime by the
associated runtime libraries. </p>
<p> <a href="#issue4.5">Issues</a> </p>
<p> 4.6. Non-ARB OpenGL extensions are
defined in <tt>glext.h</tt>, and non-ARB GLX extensions in
<tt>glxext.h</tt>. If these extensions are also defined in one of
the other required headers, this must be done conditionally so that
multiple definition problems don't occur. </p>
<p> <a href="#issue4.6">Issues</a> </p>
<p> 4.7. Vendor-specific shortcuts, such as macros for higher
performance GL entry points, are intrinsically unportable. These
should <b>not</b> be present in the required header files, but
instead in a vendor-specific header file that requires explicit
effort to access, such as defining a vendor-specific preprocessor
symbol. Likewise vendors who are not willing to include their
extensions in <tt>glext.h</tt> must isolate those extensions in
vendor-specific headers. </p>
<p> 4.8. <tt>gl.h</tt> must define the symbol
<tt>GL_OGLBASE_VERSION</tt>. This symbol must be an integer defining
the version of the ABI supported by the headers. Its value is
<i>1000 * major_version + minor_version</i> where
<i>major_version</i> and <i>minor_version</i> are the major and
minor revision numbers of this ABI standard. The primary purpose of
the symbol is to provide a compile-time test by which application
code knows whether the ABI guarantees are in force. </p>
<p> <a href="#issue4.8">Issues</a> </p>
<p> <a name="5"></a></p>
<h6>5. Extension Headers</h6>
<p> 5.1. Providing prototypes and enumerants for OpenGL extensions is
challenging because of the expected wide variety of hardware
drivers, continuing creation of extensions, and multiple sources of
header files on Linux OpenGL implementations. Some extensions will
be supported only for a specific implementation, and some will be
supported only for a specific hardware driver within that
implementation. This situation does not lend itself easily to
independent maintenance of header files definining the extensions.
<p> Instead, we require a single header file defining <b>all</b> OpenGL
extensions be supplied from a central point and updated on a
continuing basis as new extensions are added to the OpenGL <a
href="">extension registry</a> (which
is similarly centrally maintained). The central point is in the
registry at <a href=""></a>. </p>
<p> The <a href="../api/glext.h">latest version of
<tt>glext.h</tt></a> is available in the registry. It is
automatically generated from the master OpenGL function and
enumerant registries, and is updated as new extensions are
registered. The header is intended to be useful on other platforms
than Linux, particularly Windows; please let us know (via feedback
to forums) if it needs enhancement for use on another
platform. The generator scripts and &quot;.spec&quot; files used in
generating glext.h are also available. </p>
<p> Likewise for GLX, a single header defining
all GLX extensions, <a href="../api/glxext.h"><tt>glxext.h</tt></a>,
is required and is maintained centrally. </p>
<p> The registry also contains a header defining WGL
extensions, <a href="../api/wglext.h"><tt>wglext.h</tt></a>, but this is
only for use on Windows; <tt>wglext.h</tt> is <b>not</b> required by
or useful for the Linux ABI. </p>
<p> <a href="#issue5.1">Issues</a> </p>
<p> 5.2. The centrally maintained <tt>glext.h</tt> will be continually
updated, so version creep is expected. This could cause problems for
open source projects distributing source code. The proper solution
is for users to update glext.h to the latest version, but versioning
has proven helpful with other extensible aspects of OpenGL.
Therefore <tt>glext.h</tt> must include a preprocessor version
symbol <tt>GL_GLEXT_VERSION</tt>, enabling apps to do something
like: </p>
#include &lt;GL/glext.h&gt;<br>
#if GL_GLEXT_VERSION &lt; 42<br>
#error "I need a newer &lt;GL/glext.h&gt;. Please download it from"<br>
<p> <a href="#issue5.2">Issues</a> </p>
<p> 5.3. Only extensions whose fully documented specifications have been
made available to the extension registry and whose authors have
committed to shipping them in their drivers will be included in
<tt>glext.h</tt> and <tt>glxext.h</tt>. The structure of each
extension defined in these headers should resemble: </p>
#ifndef GL_EXT_<i>extensionname</i><br>
#define GL_EXT_<i>extensionname</i> 1<br>
<i> Define enumerants specific to this extension</i><br>
<i> Typedef function pointers for entry points specifically to
this extension, dynamically obtained
with glXGetProcAddressARB</i><br>
<i> Define prototypes specific to this extension</i><br>
<p> Benign redefinition of the enumerants is allowable, so these may be
outside protective <tt>#ifndef</tt> statements (this structure
results from the generator scripts used in the OpenGL SI to build
<tt>glext.h</tt>, and also because some enums may be defined by
multiple different extensions, so it could make sense to segregate
them). </p>
<p> Function pointer typedefs will use the Windows convention (e.g. the
typedef for a function <tt>glFooARB</tt> will be
<tt>PFNGLFOOARBPROC</tt>) for application source code portability.
<p> Normally, prototypes are present in
the header files, but are not visible due to conditional compilation.
To define prototypes as well as typedefs, the application must
<tt>#define GL_GLEXT_PROTOTYPES</tt> prior to including
<tt>gl.h</tt> or <tt>glx.h</tt>. <i>(Note: consistency suggests
using <tt>GLX_GLXEXT_PROTOTYPES</tt> for <tt>glxext.h</tt> -
TBD)</i>. </p>
<p> The preprocessor symbol protecting the extension declaration
must be the same as the name string identifying the extension at
runtime and in the extension registry. </p>
<p> <b>All</b> OpenGL and GLX extensions that are shipping should have a
full extension specification in the master
<a href="">
extension registry</a> on Vendors failing to document
and specify their on extensions will not be allowed to incorporate
the resulting inadequate interfaces into the ABI. </p>
<p> <a href="#issue5.3">Issues</a> </p>
<p> 5.4. <tt>glext.h</tt> is normally
<tt>#include</tt>ed by <tt>gl.h</tt>. This inclusion can be
suppressed by the application defining the preprocessor symbol
<tt>GL_GLEXT_LEGACY</tt> prior to its <tt>#include
&lt;GL/gl.h&gt;</tt>. </p>
<p> <img src="new.gif">Similarly, <tt>glxext.h</tt> is normally
<tt>#include</tt>ed by <tt>glx.h</tt>. This inclusion can be
suppressed by the application defining the preprocessor symbol
<tt>GLX_GLXEXT_LEGACY</tt> prior to its <tt>#include
&lt;GL/glx.h&gt;</tt>. </p>
<p> <a href="#issue5.4">Issues</a> </p>
<p> <a name="6"></a></p>
<h6>6. Feedback and Mailing Lists</h6>
<p> Since the ABI has been finalized, we are no longer maintaining the
oglbase-discuss mailing list used during its development. List
archives may still be available from
<a href=""></a> </p>
<p> <a name="app"></a></p>
<h6>Appendix: Open Issues</h6>
<p> <a name="issue2.1"></a>
<b>Section 2.1</b>:
Define GL datatypes for other supported Linux architectures - Alpha,
PowerPC, MIPS, etc. (in general these will be identical to the IA32
types). Note: we may want to suggest <tt>GLlong</tt> and
<tt>GLulong</tt> as 64-bit datatypes for future OpenGL revisions. </p>
<p> <a name="issue2.2"></a>
<b>Section 2.2</b>:
C++ libraries at runtime can be problematic - take the gcc/egcs
split, for example. Another potential problem area is static
constructor/destructor issues, e.g. when a C <tt>main()</tt> is
linked against GLU. Some tweaking may be required as apps running
against different ABI revisions start appearing. </p>
<p> <a name="issue3.1"></a>
<b>Section 3.1</b>:
LSB uses a more complex naming convention for libraries; we're
avoiding this at least for now, because these conventions disagree
with common practice on virtually all other Unix OpenGL
implementations. </p>
<p> <a name="issue3.2"></a>
<b>Section 3.2 (also Section 4.1)</b>:
Placing the headers and libraries in non-X11 specific locations
could impact non-GLX OpenGL implementations resident on the same
platform. It is also somewhat out of keeping with other X
extensions. However, this practice is so common on other platforms,
and non-X based OpenGL implementations are so rarely used, that we
chose to do so for build portability and "principle of least
surprise" purposes. </p>
<p> Nothing prohibits the implementation from
placing the actual library files in other locations and implementing
the required library paths as links. </p>
<p> <a name="issue3.3"></a>
<b>Section 3.3</b>:
The ABI should probably state requirements on GL libraries using C++
or other auxiliary libraries, such that no conflict will arise with
apps also using those libraries. </p>
<p> <a name="issue3.6"></a>
<b>Section 3.6</b>:
The context-independence requirement was the subject of enormous
controversy, mostly because the consequences of this requirement on
the underlying link library and driver implementations can be
significant. It is impossible to briefly recap the many pro and con
arguments briefly; refer to the <a href="#6">mailing list
archive</a> to learn more. </p>
<p> GLU does sometimes need to be extended to
properly support new GL extensions; in particular, new pixel formats
and types, or new targets for texture downloads, such as cube
mapping, should ideally be exposed through the GLU mipmap generation
routines. This is an unresolved problem, since GLU is client code
not specific to any GL driver and thus not dynamically loadable. The
best current option is for driver suppliers to make sure that
whatever GLU functionality they need is contributed to the OpenGL
Sample Implementation's GLU library. </p>
<p> Portable applications should treat the pointers
as context-dependent. </p>
<p> We haven't determined if any non-ARB extensions should be standard
entry points not requiring this dynamic lookup. As a reference
point, here are lists of GL, GLX, and GLU extensions supported by a
variety of OpenGL and Mesa implementations today (please send
additions for other platforms to the oglbase-discuss mailing list so
they can be added): </p>
<li><a href="ext/3dlabs.txt">3Dlabs</a> </li>
<li><a href="ext/compaq.txt">Compaq</a> </li>
<li><a href="ext/intergraph.txt">Intergraph/Intense 3D</a> </li>
<li><a href="ext/mesa.txt">Mesa</a> </li>
<li><a href="ext/sgi.txt">SGI (multiple platforms)</a> </li>
<li><a href="ext/sun_ultra.txt">Sun Ultra</a> </li>
<li><a href="ext/xig.txt">Xi Graphics</a> </li>
<p> <a name="issue4.5"></a>
<b>Section 4.5</b>:
Implementations may still implement only OpenGL 1.1 functionality,
but the 1.2 header and link library material must still be provided.
Since applications must already check both compile and runtime
OpenGL version numbers, no problems due to lacking support for 1.2
are expected. The next version of this standard is anticipated to
require OpenGL 1.2 support. </p>
<p> <a name="issue4.6"></a>
<b>Section 4.6</b>:
It's important that <tt>glext.h</tt> and <tt>glxext.h</tt> can be
updated from the extension registry without breaking <tt>gl.h</tt>
and <tt>glx.h</tt>. Making sure that all extension definitions are
properly protected helps to this end, as well as being good
programming practice. </p>
<p> <a name="issue4.8"></a>
<b>Section 4.8</b>:
<tt>GL_OGLBASE_VERSION</tt> is mostly provided so that apps can
determine whether to use traditional static linking of extensions,
or to dynamically query them. Unlike GL/GLX versioning, the ABI
version is not dynamically queryable at runtime. Historical
experience suggests that not providing the runtime query to begin
with is a bad decision. </p>
<p> <a name="issue5.1"></a>
<b>Section 5.1</b>:
<tt>glext.h</tt> is an exception to the Linux-centric nature of this
document, since it is already being used on other platforms. </p>
<p> <a name="issue5.2"></a>
<b>Section 5.2</b>:
Applications should <b>not</b> use the version number in
<tt>glext.h</tt> to test for presence or absence of specific
extension prototypes; this is extremely unportable and dangerous.
Always use the extension-specific symbols described in section 5.3.
<p> The header version symbol was changed from
<tt>GL_GLEXT_VERSION_EXT</tt> to <tt>GL_GLEXT_VERSION</tt> for
consistency with the <tt>GLEXT</tt> namespace the ABI group has
started using. </p>
<p> <a name="issue5.3"></a>
<b>Section 5.3</b>:
Other structures for the extension prototypes have been suggested,
such as having separate header files for each extension. Having both
structures may be preferable, but it requires more work. </p>
<p> <a name="issue5.4"></a>
<b>Section 5.4</b>:
It's important to be able to suppress automatic inclusion of
<tt>glext.h</tt> and <tt>glxext.h</tt> in order to support
compilation of legacy code not written to be ABI-aware (e.g.
assuming that extensions can be statically linked). </p>
<p> <a name="log"></a></p>
<h6>7. Change Log</h6>
<li> 10/9/2006 - updated registry links to the new location on and cleaned up other dangling wording due to the move
<li> 6/20/2000 (version 1.0) - Linux ABI approved on the oglbase-discuss
mailing list. Corrected Windows function-pointer typedef convention
in section 5.3 by appending <tt>PROC</tt>, to match what glext.h
already does. </li>
<li> 5/29/2000 (version 0.9.8) - <tt>glxext.h</tt> added to section 4.
Resolution reached on the structure of <tt>glext.h</tt> and
<tt>glxext.h</tt>, and how they are included from <tt>gl.h</tt> and
<tt>glx.h</tt>. In particular, <tt>GL_OGLBASE_VERSION</tt> symbol
defined, default inclusion of extension headers from core headers
mandated, <tt>GL_GLEXT_PROTOTYPES</tt> may be specified in order to
get extension prototypes as well as function pointer typedefs.
Renamed <tt>GL_GLEXT_VERSION_EXT</tt> to <tt>GL_GLEXT_VERSION</tt>.
<li> 4/9/2000 (version 0.9.7) - <tt>glext.h</tt> is now available
together with the ABI specification. </li>
<li> 2/22/2000 (version 0.9.6) - Revised for public comment period.
Moved open issues to the new appendix. </li>
<li> 2/8/2000 (version 0.9.5) - Removed ellipses from prototype in
section 3.6, and simplified the lists of SGI supported extensions
into one file. Mandated threadsafety in section 3.7. Moved
glXGetProcAddressARB prototype from gl.h to glx.h in section 4.4,
since the function itself was moved from gl to glX during
standardization. Restructured the page to fit into the ogl-sample
site on, next to the extension registry. Pointed to the
updated extension registry on in several places. </li>
<li> 12/9/99 (version 0.9.4) - Added Intergraph extension list in
section 3.6. </li>
<li> 12/6/99 (version 0.9.3) - Added Compaq and 3Dlabs extension
lists in section 3.6. </li>
<li> 11/23/99 (version 0.9.2) - Refined discussion of
glXGetProcAddressARB to specify that any GL or GLX function can be
queried. </li>
<li> 11/23/99 (version 0.9.1) - Summing up lots of email discussion.
Expanded participant list in section 1.4. Pinned down library
naming scheme in section 3.1. Changed to require statically
exporting all GL 1.2 / GLX 1.3 / GLU 1.3 / ARB extension entry
points in section 3.4. Changed GetProcAddress from EXT to ARB and
from gl to glX(in anticipation of ARB approval) in section 3.5.
Does <b>not</b> require a context parameter. Require Windows naming
convention for <tt>glext.h</tt> function prototypes in section 5.3.
Added a link to the list archives in section 6. </li>
<li> 9/16/1999 - Added Mesa, Sun, and Xi Graphics extension lists in
section 3.6. Added section 3.8 on transitive library dependencies
of the GL libraries. </li>
<li> 9/10/1999 - Added initial list of GL/GLX/GLU extensions
for existing platforms in section 3.6.<br>
Specified text/link colors as well as background color. </li>
<li> 9/7/1999 - Initial version. </li>
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