mirror of
https://gitee.com/openharmony/third_party_mesa3d
synced 2025-02-17 16:39:31 +00:00
46 lines
1.5 KiB
ReStructuredText
46 lines
1.5 KiB
ReStructuredText
![]() |
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
|