xenocara/dist/Mesa/docs/intro.html
2006-11-25 18:49:17 +00:00

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<TITLE>Mesa Introduction</TITLE>
<link rel="stylesheet" type="text/css" href="mesa.css"></head>
<BODY>
<H1>Introduction</H1>
<p>
Mesa is a 3-D graphics library with an API which is very similar to
that of <a href="http://www.opengl.org/" target="_parent">OpenGL</a>.*
To the extent that Mesa utilizes the OpenGL command syntax or state
machine, it is being used with authorization from <a
href="http://www.sgi.com/" target="_parent">Silicon Graphics,
Inc.</a>(SGI). However, the author does not possess an OpenGL license
from SGI, and makes no claim that Mesa is in any way a compatible
replacement for OpenGL or associated with SGI. Those who want a
licensed implementation of OpenGL should contact a licensed
vendor.
</p>
<p>
Please do not refer to the library as <em>MesaGL</em> (for legal
reasons). It's just <em>Mesa</em> or <em>The Mesa 3-D graphics
library</em>. <br>
</p>
<p>
* OpenGL is a trademark of <a href="http://www.sgi.com/"
target="_parent">Silicon Graphics Incorporated</a>.
</p>
<H1>Project History</H1>
<p>
The Mesa project was founded by me, Brian Paul. Here's a short history
of the project.
</p>
<p>
August, 1993: I begin working on Mesa in my spare time. The project
has no name at that point. I was simply interested in writing a simple
3D graphics library that used the then-new OpenGL API. I was partially
inspired by the <em>VOGL</em> library which emulated a subset of IRIS GL.
I had been programming with IRIS GL since 1991.
</p>
<p>
November 1994: I contact SGI to ask permission to distribute my OpenGL-like
graphics library on the internet. SGI was generally receptive to the
idea and after negotiations with SGI's legal department, I get permission
to release it.
</p>
<p>
February 1995: Mesa 1.0 is released on the internet. I expected that
a few people would be interested in it, but not thousands.
I was soon receiving patches, new features and thank-you notes on a
daily basis. That encouraged me to continue working on Mesa. The
name Mesa just popped into my head one day. SGI had asked me not to use
the terms <em>"Open"</em> or <em>"GL"</em> in the project name and I didn't
want to make up a new acronym. Later, I heard of the Mesa programming
language and the Mesa spreadsheet for NeXTStep.
</p>
<p>
In the early days, OpenGL wasn't available on too many systems.
It even took a while for SGI to support it across their product line.
Mesa filled a big hole during that time.
For a lot of people, Mesa was their first introduction to OpenGL.
I think SGI recognized that Mesa actually helped to promote
the OpenGL API, so they didn't feel threatened by the project.
</p>
<p>
1995-1996: I continue working on Mesa both during my spare time and during
my work hours at the Space Science and Engineering Center at the University
of Wisconsin in Madison. My supervisor, Bill Hibbard, lets me do this because
Mesa is now being using for the <a href="http://www.ssec.wisc.edu/%7Ebillh/vis.html" target="_parent">Vis5D</a> project.
</p><p>
October 1996: Mesa 2.0 is released. It implements the OpenGL 1.1 specification.
</p>
<p>
March 1997: Mesa 2.2 is released. It supports the new 3dfx Voodoo graphics
card via the Glide library. It's the first really popular hardware OpenGL
implementation for Linux.
</p>
<p>
September 1998: Mesa 3.0 is released. It's the first publicly-available
implementation of the OpenGL 1.2 API.
</p>
<p>
March 1999: I attend my first OpenGL ARB meeting. I contribute to the
development of several official OpenGL extensions over the years.
</p>
<p>
September 1999: I'm hired by Precision Insight, Inc. Mesa is a key
component of 3D hardware acceleration in the new DRI project for XFree86.
Drivers for 3dfx, 3dLabs, Intel, Matrox and ATI hardware soon follow.
</p>
<p>
October 2001: Mesa 4.0 is released.
It implements the OpenGL 1.3 specification.
</p>
<p>
November 2001: I cofound <a href="http://www.tungstengraphics.com" target="_parent">
Tungsten Graphics, Inc.</a> with Keith Whitwell, Jens Owen, David Dawes and
Frank LaMonica.
I continue to develop Mesa as part of my resposibilities with Tungsten
Graphics and as a spare-time project.
</p>
<p>
November 2002: Mesa 5.0 is released.
It implements the OpenGL 1.4 specification.
</p>
<p>
January 2003: Mesa 6.0 is released. It implements the OpenGL 1.5
specification as well as the GL_ARB_vertex_program and
GL_ARB_fragment_program extensions.
</p>
<p>
Ongoing: Mesa is used as the core of many hardware OpenGL drivers for
the XFree86 X.org X servers within the
<A href="http://dri.freedesktop.org/" target="_parent">DRI project</A>.
I continue to enhance Mesa with new extensions and features.
</p>
<H1>Major Versions</H1>
<p>
This is a summary of the major versions of Mesa. Note that Mesa's major
version number tracks OpenGL's minor version number (+1).
Work is underway to implement the OpenGL 2.0 specification.
</p>
<H2>Version 6.x features</H2>
<p>
Version 6.x of Mesa implements the OpenGL 1.5 API with the following
extensions incorporated as standard features:
</p>
<ul>
<li>GL_ARB_occlusion_query
<li>GL_ARB_vertex_buffer_object
<li>GL_EXT_shadow_funcs
</ul>
<p>
Also note that several OpenGL tokens were renamed in OpenGL 1.5
for the sake of consistency.
The old tokens are still available.
</p>
<pre>
New Token Old Token
------------------------------------------------------------
GL_FOG_COORD_SRC GL_FOG_COORDINATE_SOURCE
GL_FOG_COORD GL_FOG_COORDINATE
GL_CURRENT_FOG_COORD GL_CURRENT_FOG_COORDINATE
GL_FOG_COORD_ARRAY_TYPE GL_FOG_COORDINATE_ARRAY_TYPE
GL_FOG_COORD_ARRAY_STRIDE GL_FOG_COORDINATE_ARRAY_STRIDE
GL_FOG_COORD_ARRAY_POINTER GL_FOG_COORDINATE_ARRAY_POINTER
GL_FOG_COORD_ARRAY GL_FOG_COORDINATE_ARRAY
GL_SRC0_RGB GL_SOURCE0_RGB
GL_SRC1_RGB GL_SOURCE1_RGB
GL_SRC2_RGB GL_SOURCE2_RGB
GL_SRC0_ALPHA GL_SOURCE0_ALPHA
GL_SRC1_ALPHA GL_SOURCE1_ALPHA
GL_SRC2_ALPHA GL_SOURCE2_ALPHA
</pre>
<p>
See the
<a href="http://www.opengl.org/documentation/spec.html" target="_parent">
OpenGL specification</a> for more details.
</p>
<H2>Version 5.x features</H2>
<p>
Version 5.x of Mesa implements the OpenGL 1.4 API with the following
extensions incorporated as standard features:
</p>
<ul>
<li>GL_ARB_depth_texture
<li>GL_ARB_shadow
<li>GL_ARB_texture_env_crossbar
<li>GL_ARB_texture_mirror_repeat
<li>GL_ARB_window_pos
<li>GL_EXT_blend_color
<li>GL_EXT_blend_func_separate
<li>GL_EXT_blend_logic_op
<li>GL_EXT_blend_minmax
<li>GL_EXT_blend_subtract
<li>GL_EXT_fog_coord
<li>GL_EXT_multi_draw_arrays
<li>GL_EXT_point_parameters
<li>GL_EXT_secondary_color
<li>GL_EXT_stencil_wrap
<li>GL_EXT_texture_lod_bias (plus, a per-texture LOD bias parameter)
<li>GL_SGIS_generate_mipmap
</ul>
<H2>Version 4.x features</H2>
<p>
Version 4.x of Mesa implements the OpenGL 1.3 API with the following
extensions incorporated as standard features:
</p>
<ul>
<li>GL_ARB_multisample
<li>GL_ARB_multitexture
<li>GL_ARB_texture_border_clamp
<li>GL_ARB_texture_compression
<li>GL_ARB_texture_cube_map
<li>GL_ARB_texture_env_add
<li>GL_ARB_texture_env_combine
<li>GL_ARB_texture_env_dot3
<li>GL_ARB_transpose_matrix
</ul>
<H2>Version 3.x features</H2>
<p>
Version 3.x of Mesa implements the OpenGL 1.2 API with the following
features:
</p>
<ul>
<li>BGR, BGRA and packed pixel formats
<li>New texture border clamp mode
<li>glDrawRangeElements()
<li>standard 3-D texturing
<li>advanced MIPMAP control
<li>separate specular color interpolation
</ul>
<H2>Version 2.x features</H2>
<p>
Version 2.x of Mesa implements the OpenGL 1.1 API with the following
features.
</p>
<ul>
<li>Texture mapping:
<ul>
<li>glAreTexturesResident
<li>glBindTexture
<li>glCopyTexImage1D
<li>glCopyTexImage2D
<li>glCopyTexSubImage1D
<li>glCopyTexSubImage2D
<li>glDeleteTextures
<li>glGenTextures
<li>glIsTexture
<li>glPrioritizeTextures
<li>glTexSubImage1D
<li>glTexSubImage2D
</ul>
<li>Vertex Arrays:
<ul>
<li>glArrayElement
<li>glColorPointer
<li>glDrawElements
<li>glEdgeFlagPointer
<li>glIndexPointer
<li>glInterleavedArrays
<li>glNormalPointer
<li>glTexCoordPointer
<li>glVertexPointer
</ul>
<li>Client state management:
<ul>
<li>glDisableClientState
<li>glEnableClientState
<li>glPopClientAttrib
<li>glPushClientAttrib
</ul>
<li>Misc:
<ul>
<li>glGetPointer
<li>glIndexub
<li>glIndexubv
<li>glPolygonOffset
</ul>
</ul>
</body>
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