Some drivers have good support for GLSL but don't have the complete
set of features needed to advertise GL 2.0 support. We should accept
the three old GLSL extensions (GL_ARB_shader_objects,
GL_ARB_vertex_shader and GL_ARB_fragment_shader) to support shaders on
these drivers.
This patch splits the shader functions into four sections :- those
that are provided only in GL 2.0, those that have the same name in the
shader objects extension, those that are provided by the vertex
shader extension (they all share the same name) and those that have a
different name in the shader objects extension.
If GL 2.0 is not supported but all three of the extensions are then
the pointers to the GL2-only functions will be replaced to point to
the equivalent functions from the extensions. That way the rest of the
Cogl source doesn't have to worry about the name differences.
https://bugzilla.gnome.org/show_bug.cgi?id=677078
Reviewed-by: Robert Bragg <robert@linux.intel.com>
(cherry picked from commit 71ecb51bd20dc3053b4221961b57e5a2b1029bdf)
This adds a library that can be used instead of libGLESv2.so to provide
symbols for the GLES 2.0 api. This can be used for convenience when
using the cogl_gles2_context_ api since you don't need to manually go
through a CoglGLES2Vtable when calling the gles2 api so it should be
easier to port existing gles2 code to integrate with Cogl.
Reviewed-by: Neil Roberts <neil@linux.intel.com>
(cherry picked from commit 80d7599a2acefca7d01d8d7de9df524278ef72c5)
Some GLSL-related function prototypes are GLES2-only: GL implementations
are not required to provide them.
While Mesa is perfectly happy to return a dummy function pointer for
functions it doesn't support, other platforms are more picky, and will
return NULL.
In this particular case, this commit fixes GLSL support on OSX.
https://bugzilla.gnome.org/show_bug.cgi?id=668856
Reviewed-by: Neil Roberts <neil@linux.intel.com>
This splits up cogl-ext-functions.h in to sets of prototypes that
can be included separately so that we can include just core
gles1 or gles2 functions without any extensions.
Since eglGetProcAddress can not be used to query core client APIs
and some implementations (notably on Android) can return a garbage
pointer instead of NULL this will allow us to explicitly check
when to use eglGetProcAddress and when to use dlsym().
Reviewed-by: Neil Roberts <neil@linux.intel.com>
