2020-06-12 18:09:42 +00:00
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Off-screen Rendering
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====================
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Mesa's off-screen interface is used for rendering into user-allocated
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memory without any sort of window system or operating system
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dependencies. That is, the GL_FRONT colorbuffer is actually a buffer in
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main memory, rather than a window on your display.
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The OSMesa API provides three basic functions for making off-screen
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renderings: OSMesaCreateContext(), OSMesaMakeCurrent(), and
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OSMesaDestroyContext(). See the Mesa/include/GL/osmesa.h header for more
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information about the API functions.
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The OSMesa interface may be used with any of three software renderers:
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#. llvmpipe - this is the high-performance Gallium LLVM driver
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#. softpipe - this it the reference Gallium software driver
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#. swrast - this is the legacy Mesa software rasterizer
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There are several examples of OSMesa in the mesa/demos repository.
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Building OSMesa
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---------------
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Configure and build Mesa with something like:
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::
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meson builddir -Dosmesa=gallium -Dgallium-drivers=swrast -Ddri-drivers=[] -Dvulkan-drivers=[] -Dprefix=$PWD/builddir/install
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ninja -C builddir install
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Make sure you have LLVM installed first if you want to use the llvmpipe
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driver.
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When the build is complete you should find:
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::
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$PWD/builddir/install/lib/libOSMesa.so (swrast-based OSMesa)
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2020-09-28 11:49:20 +00:00
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$PWD/builddir/install/lib/gallium/libOSMsea.so (Gallium-based OSMesa)
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2020-06-12 18:09:42 +00:00
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Set your LD_LIBRARY_PATH to point to $PWD/builddir/install to use the
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libraries
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When you link your application, link with -lOSMesa
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