This reduces the size of the geometry that needs to be uploaded by
one-third, and allows kwin to take advantage of the post-transform
cache in the GPU.
Only the subset of functions available in core contexts is resolved,
except for glGetnTexImageARB() and glGetnUniformivARB(), which are
not used by kwin.
Instead of setting the function pointers to NULL when the extension isn't
supported, kwin provides its own implementations that call the non-robust
versions of the functions. This is so callers don't have to check if the
extension is supported before calling the functions.
Note to me: always rebuild with all possible build options if something
is changed.
Sorry for the inconvenience and thanks to the early report of the issue.
BUG: 307866
FIXED-IN: 4.10
According to the OpenGL ABI for Linux GLX 1.3 is a minimum requirement.
Therefore we do not need to resolve the symbols which are present in that
version.
KWin did always require at least 1.3, for all the resolved functions
there were checks in the Scene, but they might have been incorrect.
Instead now the GLX version is checked and OpenGL compositing is blocked
if there is not at least GLX 1.3.
REVIEW: 106704
glBlendColor has been added to OpenGL 1.2 which means it is part of
the OpenGL ABI defined for Linux.
See http://www.opengl.org/registry/ABI/ section 3.4.
The Egl backend is decoupled from the OpenGL ES build option which makes
it possible to use it as a replacement for glx.
To make this possible a new build flag is added when egl is available at
compile time and any egl specific code is now ifdefed with this flag
instead of the gles flag. In addition at runtime a windowing system enum
value is passed to the various detect methods to have egl/glx specific
detection for e.g. function pointer resolving.
By default egl is used if compiled with OpenGL ES, otherwise glx is used.
But in the non-gles case the windowing system can be selected through the
new environment variable KWIN_OPENGL_INTERFACE. Setting this variable to
"egl" the EglOnXBackend is used.
REVIEW: 106632
The EGL path had no support for presenting sub-regions of the screen, we can
leverage EGL_NV_post_sub_buffer for that. This wouldn't be a win if we didn't
have to opt-out of flipping.
REVIEW: 102889
Second part of cleaning up the lib directory: the effects library
now lives in libkwineffects/ directory.
For existing effects nothing changes as the install path is unchanged.
The change obsoletes the lib/ directory.
As glplatform.h has not yet been exported I dared to export it and
adjust the places where it is used.
CCMAIL: kwin@kde.org