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lib/mesa/docs/osmesa.rst

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+Off-screen Rendering
+====================
+
+Mesa's off-screen interface is used for rendering into user-allocated
+memory without any sort of window system or operating system
+dependencies. That is, the GL_FRONT colorbuffer is actually a buffer in
+main memory, rather than a window on your display.
+
+The OSMesa API provides three basic functions for making off-screen
+renderings: OSMesaCreateContext(), OSMesaMakeCurrent(), and
+OSMesaDestroyContext(). See the Mesa/include/GL/osmesa.h header for more
+information about the API functions.
+
+The OSMesa interface may be used with the gallium software renderers:
+
+#. LLVMpipe - this is the high-performance Gallium LLVM driver
+#. Softpipe - this is the reference Gallium software driver
+
+There are several examples of OSMesa in the mesa/demos repository.
+
+Building OSMesa
+---------------
+
+Configure and build Mesa with something like:
+
+.. code-block:: console
+
+   meson builddir -Dosmesa=true -Dgallium-drivers=swrast -Dvulkan-drivers=[] -Dprefix=$PWD/builddir/install
+   ninja -C builddir install
+
+Make sure you have LLVM installed first if you want to use the LLVMpipe
+driver.
+
+When the build is complete you should find:
+
+::
+
+   $PWD/builddir/install/lib/libOSMesa.so
+
+Set your LD_LIBRARY_PATH to point to $PWD/builddir/install to use the
+libraries
+
+When you link your application, link with -lOSMesa