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)
The list of extension names in COGL_EXT_BEGIN should be a zero
separated list of strings which is terminated by an empty string. The
name for the GL_ARB_shader_objects extension was missing the zero
separator so presumably it was relying on the following byte to happen
to be a zero in order not to crash.
Reviewed-by: Robert Bragg <robert@linux.intel.com>
(cherry picked from commit f63381f23fa8b0b17e030561940b8a38efff221f)
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)
GL_ARB_sampler_objects provides a GL object which overrides the
sampler state part of a texture object with different values. The
sampler state that Cogl currently exposes is the wrap modes and
filters. Cogl exposes the state as part of the pipeline layer state
but without this extension GL only exposes it as part of the texture
object state. This means that it won't work to use a single texture
multiple times in one primitive with different sampler states. It also
makes switching between different sampler states with a single texture
not terribly efficient because it has to change the texture object
state every time.
This patch adds a cache for sampler states in a shared hash table
attached to the CoglContext. The entire set of parameters for the
sampler state is used as the key for the hash table. When a unique
state is encountered the sampler cache will create a new entry,
otherwise it will return a const pointer to an existing entry. That
means we can have a single pointer to represent any combination of
sampler state.
Pipeline layers now just store this single pointer rather than storing
all of the sampler state. The two separate state flags for wrap modes
and filters have now been combined into one. It should be faster to
compare the sampler state now because instead of comparing each value
it can just compare the pointers to the cached sampler entries. The
hash table of cached sampler states should only need to perform its
more expensive hash on the state when a property is changed on a
pipeline, not every time it is flushed.
When the sampler objects extension is available each cached sampler
state will also get a sampler object to represent it. The common code
to flush the GL state will now simply bind this object to a unit
instead of flushing the state though the CoglTexture when possible.
Reviewed-by: Robert Bragg <robert@linux.intel.com>
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>
