| 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 any of three software renderers: |
| |
| #. llvmpipe - this is the high-performance Gallium LLVM driver |
| #. softpipe - this it the reference Gallium software driver |
| #. swrast - this is the legacy Mesa software rasterizer |
| |
| There are several examples of OSMesa in the mesa/demos repository. |
| |
| Building OSMesa |
| --------------- |
| |
| Configure and build Mesa with something like: |
| |
| :: |
| |
| meson builddir -Dosmesa=gallium -Dgallium-drivers=swrast -Ddri-drivers=[] -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 (swrast-based OSMesa) |
| $PWD/builddir/install/lib/gallium/libOSMsea.so (gallium-based OSMesa) |
| |
| Set your LD_LIBRARY_PATH to point to $PWD/builddir/install to use the |
| libraries |
| |
| When you link your application, link with -lOSMesa |
