This adds a new CoglDriver for GL 3 called COGL_DRIVER_GL3. When
requested, the GLX, EGL and SDL2 winsyss will set the necessary
attributes to request a forward-compatible core profile 3.1 context.
That means it will have no deprecated features.
To simplify the explosion of checks for specific combinations of
context->driver, many of these conditionals have now been replaced
with private feature flags that are checked instead. The GL and GLES
drivers now initialise these private feature flags depending on which
driver is used.
The fixed function backends now explicitly check whether the fixed
function private feature is available which means the GL3 driver will
fall back to always using the GLSL progend. Since Rob's latest patches
the GLSL progend no longer uses any fixed function API anyway so it
should just work.
The driver is currently lower priority than COGL_DRIVER_GL so it will
not be used unless it is specificly requested. We may want to change
this priority at some point because apparently Mesa can make some
memory savings if a core profile context is used.
In GL 3, getting the combined extensions string with glGetString is
deprecated so this patch changes it to use glGetStringi to build up an
array of extensions instead. _cogl_context_get_gl_extensions now
returns this array instead of trying to return a const string. The
caller is expected to free the array.
Some issues with this patch:
• GL 3 does not support GL_ALPHA format textures. We should probably
make this a feature flag or something. Cogl uses this to render text
which currently just throws a GL error and breaks so it's pretty
important to do something about this before considering the GL3
driver to be stable.
• GL 3 doesn't support client side vertex buffers. This probably
doesn't matter because CoglBuffer won't normally use malloc'd
buffers if VBOs are available, but it might but worth making
malloc'd buffers a private feature and forcing it not to use them.
• GL 3 doesn't support the default vertex array object. This patch
just makes it create and bind a single non-default vertex array
object which gets used just like the normal default object. Ideally
it would be good to use vertex array objects properly and attach
them to a CoglPrimitive to cache the state.
Reviewed-by: Robert Bragg <robert@linux.intel.com>
(cherry picked from commit 66c9db993595b3a22e63f4c201ea468bc9b88cb6)
Since we used to support hybrid fixed-function + glsl pipelines when
running with OpenGL there were numerous differences in how we handled
codegen and uniform updates between GLES2 and full OpenGL. Now that we
only support end-to-end glsl pipelines this patch can largely unify how
we handle GLES2 and OpenGL.
Most notably we now never use the builtin attribute names. This should
also make it easy for us to support creating strict OpenGL 3.1 contexts
where the builtin names have been removed.
Reviewed-by: Neil Roberts <neil@linux.intel.com>
(cherry picked from commit 2701b93f159bf2d3387cedf2d06fe921ad5641f3)
As part of an on-going effort to be able to support non-opengl drivers
for Cogl this splits out the opengl specific code from cogl-buffer.c
into driver/gl/cogl-buffer-gl.c
Reviewed-by: Neil Roberts <neil@linux.intel.com>
(cherry picked from commit 4d7094a979ff2cbbe4054f4a44ca05fc41a9e447)
The buffer and bitmap _bind() functions are GL specific so to clarify
that, this patch adds a _gl infix to these functions, though it doesn't
yet move the implementations out into gl specific files.
Reviewed-by: Neil Roberts <neil@linux.intel.com>
(cherry picked from commit 6371fbb9637d88ff187dfb6c4bcd18468ba44d19)
As part of an on-going effort to enable non-opengl drivers for Cogl this
splits out the GL specific code in cogl-attribute.c into
cogl/driver/gl/cogl-attribute-gl.c
Reviewed-by: Neil Roberts <neil@linux.intel.com>
(cherry picked from commit 7e20c39c47fa176aa5062867ff273bc2c41a2f22)
