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<h1>The Mesa 3D Graphics Library</h1>
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<h1>Off-screen Rendering</h1>
<p>
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.
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<p>
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.
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<p>
The OSMesa interface may be used with any of three software renderers:
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<ol>
<li>llvmpipe - this is the high-performance Gallium LLVM driver
<li>softpipe - this it the reference Gallium software driver
<li>swrast - this is the legacy Mesa software rasterizer
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<p>
There are several examples of OSMesa in the mesa/demos repository.
</p>
<h1>Building OSMesa</h1>
<p>
Configure and build Mesa with something like:
<pre>
configure --enable-osmesa --disable-driglx-direct --disable-dri --with-gallium-drivers=swrast
make
</pre>
<p>
Make sure you have LLVM installed first if you want to use the llvmpipe driver.
</p>
<p>
When the build is complete you should find:
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<pre>
lib/libOSMesa.so (swrast-based OSMesa)
lib/gallium/libOSMsea.so (gallium-based OSMesa)
</pre>
<p>
Set your LD_LIBRARY_PATH to point to one directory or the other to select
the library you want to use.
</p>
<p>
When you link your application, link with -lOSMesa
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