Mesa Frequently Asked Questions
-Last updated: 7 March 2003 +Last updated: 9 October 2012@@ -26,155 +35,192 @@ Last updated: 7 March 2003 - -
1. High-level Questions and Answers
+1. High-level Questions and Answers
-1.1 What is Mesa?
+1.1 What is Mesa?
-Mesa is an open-source implementation of the OpenGL specification. -OpenGL is a high-level programming library for interactive 3D graphics. -See the OpenGL website for more +Mesa is an open-source implementation of the OpenGL specification. +OpenGL is a programming library for writing interactive 3D applications. +See the OpenGL website for more information.
-Mesa 5.0.x supports the OpenGL 1.4 specification. +Mesa 9.x supports the OpenGL 3.1 specification.
1.2 Does Mesa support/use graphics hardware?
-Yes. Specifically, Mesa serves as the OpenGL core for the XFree86/DRI -OpenGL drivers. See the DRI website for -more information. -
--There have been other hardware drivers for Mesa over the years (such as -the 3Dfx Glide/Voodoo driver, an old S3 driver, etc) but the DRI drivers -are the modern ones. +Yes. Specifically, Mesa serves as the OpenGL core for the open-source DRI +drivers for X.org.
- -1.3 What purpose does (software) Mesa serve today?
--Commercial, hardware-accelerated OpenGL implementations are available for -many operating systems today. +
-
+
- See the DRI website + for more information. +
- See 01.org + for more information about Intel drivers. +
- See nouveau.freedesktop.org + for more information about Nouveau drivers. +
- See www.x.org/wiki/RadeonFeature + for more information about Radeon drivers. +
1.3 What purpose does Mesa serve today?
++Hardware-accelerated OpenGL implementations are available for most popular +operating systems today. Still, Mesa serves at least these purposes:
-
-
- Mesa is used as the core of the XFree86/DRI hardware drivers. -
- Mesa is quite portable and allows OpenGL to be used on systems that have - no other OpenGL solution. -
- Software rendering with Mesa serves as a reference for validating the +
- Mesa is used as the core of the open-source X.org DRI hardware drivers. -
- A software implementation of OpenGL is useful for experimentation, such - as testing new rendering techniques. -
- Mesa can render images with deep color channels: 16-bit integer and 32-bit - floating point color channels are supported. + +
- Mesa is quite portable and allows OpenGL to be used on systems + that have no other OpenGL solution. + +
- Software rendering with Mesa serves as a reference for validating the + hardware drivers. + +
- A software implementation of OpenGL is useful for experimentation, + such as testing new rendering techniques. + +
- Mesa can render images with deep color channels: 16-bit integer + and 32-bit floating point color channels are supported. This capability is only now appearing in hardware. -
- Mesa's internal limits (max lights, clip planes, texture size, etc) can be + +
- Mesa's internal limits (max lights, clip planes, texture size, etc) can be changed for special needs (hardware limits are hard to overcome). -
1.4 How do I upgrade my DRI installation to use a new Mesa release?
+ +1.4 What's the difference between "Stand-Alone" Mesa and the DRI drivers?
-You don't! The Mesa source code lives inside the XFree86/DRI source tree -and gets compiled into the individual DRI driver modules. -If you try to install Mesa over an XFree86/DRI installation, you'll lose -hardware rendering (because Mesa's libGL.so is different than the XFree86 -libGL.so). +Stand-alone Mesa is the original incarnation of Mesa. +On systems running the X Window System it does all its rendering through +the Xlib API:
+-
+
- The GLX API is supported, but it's really just an emulation of the + real thing. +
- The GLX wire protocol is not supported and there's no OpenGL extension + loaded by the X server. +
- There is no hardware acceleration. +
- The OpenGL library, libGL.so, contains everything (the programming API, + the GLX functions and all the rendering code). +
+Alternately, Mesa acts as the core for a number of OpenGL hardware drivers +within the DRI (Direct Rendering Infrastructure): +
-
+
- The libGL.so library provides the GL and GLX API functions, a GLX + protocol encoder, and a device driver loader. +
- The device driver modules (such as r200_dri.so) contain a built-in + copy of the core Mesa code. +
- The X server loads the GLX module. + The GLX module decodes incoming GLX protocol and dispatches the commands + to a rendering module. + For the DRI, this module is basically a software Mesa renderer. +
1.5 How do I upgrade my DRI installation to use a new Mesa release?
-The DRI developers will incorporate the latest release of Mesa into the -DRI drivers when the time is right. +This wasn't easy in the past. +Now, the DRI drivers are included in the Mesa tree and can be compiled +separately from the X server. +Just follow the Mesa compilation instructions.
-1.5 Are there other open-source implementations of OpenGL?
+ +1.6 Are there other open-source implementations of OpenGL?
Yes, SGI's -OpenGL Sample Implemenation (SI) is available. +OpenGL Sample Implementation (SI) is available. The SI was written during the time that OpenGL was originally designed. Unfortunately, development of the SI has stagnated. Mesa is much more up to date with modern features and extensions.
+ ++Vincent is +an open-source implementation of OpenGL ES for mobile devices. +
-miniGL is a subset of OpenGL -for PalmOS devices. +miniGL +is a subset of OpenGL for PalmOS devices. -TinyGL is another -subset of OpenGL. +
+TinyGL +is a subset of OpenGL.
+-There may be others but Mesa is the most popular and feature-complete. +SoftGL +is an OpenGL subset for mobile devices.
--
+
+Chromium +isn't a conventional OpenGL implementation (it's layered upon OpenGL), +but it does export the OpenGL API. It allows tiled rendering, sort-last +rendering, etc. +
++ClosedGL +is an OpenGL subset library for TI graphing calculators. +
- -2. Compilation and Installation Problems
++There may be other open OpenGL implementations, but Mesa is the most +popular and feature-complete. +
-2.1 What's the easiest way to install Mesa?
- + ++
-
2.2 Running configure; make
Doesn't Work
-cd Mesa-x.y.z - cp Makefile.X11 Makefile - make --You'll see a list of system configurations from which to choose. -For example: -
make linux-x86 -- +
2. Compilation and Installation Problems
+ -2.3 Mesa still doesn't compile
+2.1 What's the easiest way to install Mesa?
+If you're using a Linux-based system, your distro CD most likely already +has Mesa packages (like RPM or DEB) which you can easily install. + -2.4 I get undefined symbols such as bgnpolygon, v3f, etc...
+2.2 I get undefined symbols such as bgnpolygon, v3f, etc...
+ -2.5 Where is the GLUT library?
+2.3 Where is the GLUT library?
+GLUT (OpenGL Utility Toolkit) is no longer in the separate MesaGLUT-x.y.z.tar.gz file. +If you don't already have GLUT installed, you should grab +freeglut. + +2.4 Where is the GLw library?
++GLw (OpenGL widget library) is now available from a separate git repository. Unless you're using very old Xt/Motif applications with OpenGL, you shouldn't need it. +
+ -2.6 What's the proper place for the libraries and headers?
+2.5 What's the proper place for the libraries and headers?
-On Linux-based systems you'll want to follow the -Linux ABI -standard. +On Linux-based systems you'll want to follow the +Linux ABI standard. Basically you'll want the following:
-
@@ -188,49 +234,49 @@ Basically you'll want the following:
- /usr/lib/libGL.so.1 - a symlink to libGL.so.1.xyz
- /usr/lib/libGL.so.xyz - the actual OpenGL/Mesa library. xyz denotes the Mesa version number. -
- /usr/lib/libGLU.so - a symlink to libGLU.so.1 -
- /usr/lib/libGLU.so.1 - a symlink to libGLU.so.1.3.xyz -
- /usr/lib/libGLU.so.xyz - the OpenGL Utility library. xyz denotes the Mesa -version number.
-After installing XFree86 and the DRI drivers, some of these files
-may be symlinks into the /usr/X11R6/ tree.
+When configuring Mesa, there are three autoconf options that affect the install
+location that you should take care with: --prefix
,
+--libdir
, and --with-dri-driverdir
. To install Mesa
+into the system location where it will be available for all programs to use, set
+--prefix=/usr
. Set --libdir
to where your Linux
+distribution installs system libraries, usually either /usr/lib
or
+/usr/lib64
. Set --with-dri-driverdir
to the directory
+where your Linux distribution installs DRI drivers. To find your system's DRI
+driver directory, try executing find /usr -type d -name dri
. For
+example, if the find
command listed /usr/lib64/dri
,
+then set --with-dri-driverdir=/usr/lib64/dri
.
-The old-style Makefile system doesn't install the Mesa libraries; it's -up to you to copy them (and the headers) to the right place. -
-
-The GLUT header and library should go in the same directories.
+After determining the correct values for the install location, configure Mesa
+with ./configure --prefix=/usr --libdir=xxx --with-dri-driverdir=xxx
+and then install with sudo make install
.
- -
3. Runtime / Rendering Problems
+3. Runtime / Rendering Problems
-3.1 Rendering is slow / why isn't my graphics hardware being used?
+3.1 Rendering is slow / why isn't my graphics hardware being used?
- +If Mesa can't use its hardware accelerated drivers it falls back on one of its software renderers. +(eg. classic swrast, softpipe or llvmpipe) + + +
+If you're using a hardware accelerated driver you want direct rendering: Yes
.
+
-If your DRI-based driver isn't working, go to the -DRI website for trouble-shooting information. +If your DRI-based driver isn't working, go to the +DRI website for trouble-shooting information.
@@ -238,8 +284,8 @@ hardware it has detected.Make sure the ratio of the far to near clipping planes isn't too great. Look - -here for details. +here +for details.
Mesa uses a 16-bit depth buffer by default which is smaller and faster
@@ -285,17 +331,16 @@ will fix the problem.
-
-
4. Developer Questions
+4. Developer Questions
-4.1 How can I contribute?
+4.1 How can I contribute?
-First, join the Mesa3d-dev mailing list. That's where Mesa development -is discussed. -
+First, join the mesa-dev mailing list. +That's where Mesa development is discussed. +-The -OpenGL Specification is the bible for OpenGL implemention work. +The +OpenGL Specification is the bible for OpenGL implementation work. You should read it.
Most of the Mesa development work involves implementing new OpenGL @@ -312,12 +357,12 @@ target hardware/operating system.
The best way to get started is to use an existing driver as your starting point. -For a software driver, the X11 and OSMesa drivers are good examples. -For a hardware driver, the Radeon and R200 DRI drivers are good examples. +For a classic hardware driver, the i965 driver is a good example. +For a Gallium3D hardware driver, the r300g, r600g and the i915g are good examples.
The DRI website has more information about writing hardware drivers. The process isn't well document because the Mesa driver interface changes -over time, and we seldome have spare time for writing documentation. +over time, and we seldom have spare time for writing documentation. That being said, many people have managed to figure out the process.
@@ -326,5 +371,22 @@ the archives) is a good way to get information.
+4.3 Why isn't GL_EXT_texture_compression_s3tc implemented in Mesa?
++The specification for the extension +indicates that there are intellectual property (IP) and/or patent issues +to be dealt with. +
+We've been unsuccessful in getting a response from S3 (or whoever owns +the IP nowadays) to indicate whether or not an open source project can +implement the extension (specifically the compression/decompression +algorithms). +
++In the mean time, a 3rd party +plug-in library is available. +
+ +