X-Git-Url: https://git.libre-soc.org/?a=blobdiff_plain;f=docs%2Ffaq.html;h=4e79bb167f6553ae98dbaf1cf9f0230c3176b95b;hb=b940b2fd163f39576ddee23cee7fa60aa94f98fd;hp=fa90d5bfe819c569509370896003a5e743ffdfb5;hpb=297309ce2366dcc81df5403eb56547f1feedd0e0;p=mesa.git diff --git a/docs/faq.html b/docs/faq.html index fa90d5bfe81..4e79bb167f6 100644 --- a/docs/faq.html +++ b/docs/faq.html @@ -7,9 +7,16 @@ +
+

The Mesa 3D Graphics Library

+
+ + +
+

Mesa Frequently Asked Questions

-Last updated: 21 August 2006 +Last updated: 9 October 2012

@@ -38,21 +45,25 @@ See the OpenGL website for more information.

-Mesa 6.x supports the OpenGL 1.5 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 open-source DRI -drivers for XFree86/X.org. 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. +drivers for X.org.

+

1.3 What purpose does Mesa serve today?

@@ -61,7 +72,7 @@ operating systems today. Still, Mesa serves at least these purposes:

-

1.4 What's the difference between"Stand-Alone" Mesa and the DRI drivers?

+

1.4 What's the difference between "Stand-Alone" Mesa and the DRI drivers?

Stand-alone Mesa is the original incarnation of Mesa. On systems running the X Window System it does all its rendering through @@ -125,43 +136,41 @@ Just follow the Mesa compilation instructions.

1.6 Are there other open-source implementations of OpenGL?

-Yes, SGI's -OpenGL Sample Implemenation (SI) is available. +Yes, SGI's +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 +Vincent is an open-source implementation of OpenGL ES for mobile devices.

-miniGL +miniGL is a subset of OpenGL for PalmOS devices.

-TinyGL is a subset of OpenGL. +TinyGL +is a subset of OpenGL.

-SoftGL +SoftGL is an OpenGL subset for mobile devices.

-Chromium +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. +ClosedGL +is an OpenGL subset library for TI graphing calculators.

@@ -211,8 +220,7 @@ GLw (OpenGL widget library) is now available from a separate Linux ABI standard. +Linux ABI standard. Basically you'll want the following:

-After installing XFree86/X.org and the DRI drivers, some of these files -may be symlinks into the /usr/X11R6/ tree. -

-

-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. +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 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.



@@ -250,24 +261,22 @@ The GLUT header and library should go in the same directories.

3.1 Rendering is slow / why isn't my graphics hardware being used?

-Stand-alone Mesa (downloaded as MesaLib-x.y.z.tar.gz) doesn't have any -support for hardware acceleration (with the exception of the 3DFX Voodoo -driver). -

-

-What you really want is a DRI or NVIDIA (or another vendor's OpenGL) driver -for your particular hardware. +If Mesa can't use its hardware accelerated drivers it falls back on one of its software renderers. +(eg. classic swrast, softpipe or llvmpipe)

You can run the glxinfo program to learn about your OpenGL library. -Look for the GL_VENDOR and GL_RENDERER values. -That will identify who's OpenGL library you're using and what sort of +Look for the OpenGL vendor and OpenGL renderer values. +That will identify who's OpenGL library with which driver you're using and what sort of hardware it has detected.

+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. +DRI website for trouble-shooting information.

@@ -275,8 +284,8 @@ If your DRI-based driver isn't working, go to the

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 @@ -318,19 +327,6 @@ Basically, applying a translation of (0.375, 0.375, 0.0) to your coordinates will fix the problem.

-

3.6 How can I change the maximum framebuffer size in Mesa's -swrast backend?

-

-These can be overridden by using the --with-max-width and ---with-max-height options. The two need not be equal. -

-Do note that Mesa uses these values to size some internal buffers, -so increasing these sizes will cause Mesa to require additional -memory. Furthermore, increasing these limits beyond 4096 -may introduce rasterization artifacts; see the leading comments in -src/mesa/swrast/s_tritemp.h. -

-

@@ -339,13 +335,12 @@ may introduce rasterization artifacts; see the leading comments in

4.1 How can I contribute?

-First, join the Mesa3d-dev -mailing list. +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 @@ -362,12 +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.

@@ -378,20 +373,20 @@ 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 +The specification for the extension indicates that there are intellectual property (IP) and/or patent issues to be dealt with.

-

We've been unsucessful in getting a response from S3 (or whoever owns +

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. +In the mean time, a 3rd party +plug-in library is available.

+