When iterating through all the possible window systems trying to find
one we can successfully connect we now associated the current winsys
vtable with the renderer before calling winsys->renderer_connect in case
the implementation calls some other Cogl API that expects to be able to
determine the current winsys. For example calling _cogl_get_proc_address
when querying winsys extensions as part of a successful connect will
need to get at the current winsys vtable.
This adds internal API to be able to wrap a wayland buffer as a
CoglTexture2D. There is a --enable-wayland-egl-server option to decide
if Cogl should support this feature and potentially any EGL based winsys
could support this through the EGL_KHR_image_base and
EGL_WL_bind_display extensions.
By using the EGL_KHR_image_base/pixmap extensions this adds support for
wrapping X11 pixmaps as CoglTexture2D textures. Clutter will
automatically take advantage of this if using the
ClutterX11TexturePixmap actor.
This adds an internal texture_2d constructor that can wrap an EGLImage
as a CoglTexture2D. The plan is to utilize this for texture-from-pixmap
support with EGL as well as creating textures from wayland buffers.
Instead of the stub winsys being a special case set of #ifdef'd code
used when COGL_HAS_FULL_WINSYS wasn't defined, the stub winsys now
implements a CoglWinsysVtable like all other winsys backends (it's just
that everything is a NOP). This way we can get rid of the
COGL_HAS_FULL_WINSYS define and also the stub winsys can be runtime
selected whereas before it was incompatible with all other winsys
backends.
Since we no longer have any xlib based backends in Clutter that depend
on the stub winsys in Cogl we can now remove all the special case code
we had for this in cogl-xlib.c
This exposes a CoglTexture2D typedef and adds the following experimental
API:
cogl_is_texture_2d
cogl_texture_2d_new_with_size
cogl_texture_2d_new_from_data
cogl_texture_2d_new_from_foreign
Since this is experimental API you need to define
COGL_ENABLE_EXPERIMENTAL_API before including cogl.h.
Note: With these new entrypoints we now expect a CoglContext pointer to
be passed in, instead of assuming there is a default context. The aim is
that for Cogl 2.0 we won't have a default context so this is a step in
that direction.
This validates that the viewport width and height arguments are positive
values in _cogl_framebuffer_set_viewport. In addition, just before
calling glViewport we also assert that something else hasn't gone amiss
and that the internal viewport width/height values we track are still
positive before passing to glViewport which generates an error for
negative values.
This reverts commit b2e41f1bfa.
We are backing out the quartz specific stub winsys since we can simply
use the generic stub winsys on quartz until we develop a standalone
winsys. Since we plan on removing all special cases for the stub winsys
by handling with a winsys vtable like all the others it's better if we
don't introduce a quartz specific stub.
This reverts commit eb81ec945c.
We are backing out the quartz specific stub winsys since we can simply
use the generic stub winsys on quartz until we develop a standalone
winsys. Since we plan on removing all special cases for the stub winsys
by handling with a winsys vtable like all the others it's better if we
don't introduce a quartz specific stub.
Previously whenever the journal is flushed a new vertex array would be
created to contain the vertices. To avoid the overhead of reallocating
a buffer every time, this patch makes it use a pool of 8 buffers which
are cycled in turn. The buffers are never destroyed but instead the
data is replaced. The journal should only ever be using one buffer at
a time but we cache more than one buffer anyway in case the GL driver
is internally using the buffer in which case mapping the buffer may
cause it to create a new buffer anyway.
When flushing a pipeline that has more layers than the previous
pipeline, the fixed function fragend is supposed to detect that the
texture unit previously had no texture target enabled and then enable
it. However the logic for checking whether the unit was enabled was
broken due to a typing failure when unit->enabled and
unit->current_gl_target were combined into one value in commit
6b7139b0. This was breaking some of the conformance tests when the
fixed function fragend is used.
https://bugzilla.gnome.org/show_bug.cgi?id=650979
The CoglPipeline code uses a combination of GL_MAX_TEXTURE_COORDS,
GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS and GL_MAX_TEXTURE_UNITS to
determine the maximum number of layers to allow in a pipeline. However
on fixed function hardware that doesn't advertise either GLSL or ARBfp
it was still using the first two enums which will probably just return
0 and set a GLerror. This meant that we effectively didn't support
using any layers on purely fixed function hardware. This patch changes
it to only use those two enums if the appropriate extensions are
advertised and to always use GL_MAX_TEXTURE_UNITS except on GLES2
where there is no fixed function.
https://bugzilla.gnome.org/show_bug.cgi?id=650966
The native window type of the EGL/Android winsys is ANativeWinow*. The
Android NDK gives you a pointer to this ANativeWindow and you just need
to configure that window using the EGLConfig you are choosing when
creating the context.
This means you have to know the ANativeWindow* window before creating
the context. This is solved here by just having a global variable you
can set with cogl_android_set_native_window() before creating the
context. This is a bit ugly though, and it conceptually belongs to the
OnScreen creation to know which ANativeWindow* to use. This would need a
"lazy context creation" mechanism, waiting for the user to create the
OnScreen to initialize the GL context.
With GLES 1, frame buffers are a optional extensions. We need to make
sure the pointer exist before calling the function and do that by just
checkout the corresponding feature.
When try_create_context() returns saying that it has to be run again to
try to create a context with an alternate configuration, it might not
have a GError set (and in fact it does not right now).
g_clear_error() handles that case where error is still NULL;
Early implementations provided only a GLES/egl.h while Khronos's
implementer guide now states EGL/egl.h is the One. Some implementations
keep a GLES/egl.h wrapper around EGL/egl.h for backward compatibility
while others provide EGL/egl.h only.
Also took the opportunity to factorize a bit this inclusion in
cogl-defines.h.
Instead of simply extending the cogl_pipeline_ namespace to add api for
controlling the depth testing state we now break the api out. This adds
a CoglDepthState type that can be stack allocated. The members of the
structure are private but we have the following API to setup the state:
cogl_depth_state_init
cogl_depth_state_set_test_enabled
cogl_depth_state_get_test_enabled
cogl_depth_state_set_test_function
cogl_depth_state_get_test_function
cogl_depth_state_set_writing_enabled
cogl_depth_state_get_writing_enabled
cogl_depth_state_set_range
cogl_depth_state_get_range
This removes the following experimental API which is now superseded:
cogl_material_set_depth_test_enabled
cogl_material_get_depth_test_enabled
cogl_material_set_depth_test_function
cogl_material_get_depth_test_function
cogl_material_set_depth_writing_enabled
cogl_material_get_depth_writing_enabled
cogl_material_set_depth_range
cogl_material_get_depth_range
Once a CoglDepthState structure is setup it can be set on a pipeline
using cogl_pipeline_set_depth_state().
Commit 3c1e83c7 changed uses of arrays of CoglAttributes to take a
length instead of being NULL terminated. In cogl_primitive_new it was
still adding the NULL terminator to the array it passes to
cogl_primitive_new_with_attributes but then it was also including this
terminator in the count so it would just segfault when it tries to ref
the NULL pointer. Also _cogl_primitive_new_with_attributes_unref was
still trying to detect the NULL terminator so it would also crash.
cogl/cogl-pango.h can't be included unless the include directory for
Pango is given in the compiler flags. In an application, it is
expected that if they are using this header then they would pull in
cogl-pango-1.0.pc which would provide this. However when building Cogl
itself we might be building without Pango support so the Makefile
can't rely on PANGO_CFLAGS. This was breaking building the
introspection data because cogl-pango.h was listed as one of the files
to scan but it can't be included.
For the first iteration of the CoglAttribute API several of the new
functions accepted a pointer to a NULL terminated list of CoglAttribute
pointers - probably as a way to reduce the number of arguments required.
This style isn't consistent with existing Cogl APIs though and so we now
explicitly pass n_attributes arguments and don't require the NULL
termination.
This is part of a broader cleanup of some of the experimental Cogl API.
One of the reasons for this particular rename is to switch away from
using the term "Array" which implies a regular, indexable layout which
isn't the case. We also want to strongly imply a relationship between
CoglBuffers and CoglIndexBuffers and be consistent with the
CoglAttributeBuffer and CoglPixelBuffer APIs.
This is part of a broader cleanup of some of the experimental Cogl API.
One of the reasons for this particular rename is to switch away from
using the term "Array" which implies a regular, indexable layout which
isn't the case. We also want to strongly imply a relationship between
CoglBuffers and CoglPixelBuffers and be consistent with the
CoglAttributeBuffer and CoglIndexBuffer APIs.
This is part of a broader cleanup of some of the experimental Cogl API.
One of the reasons for this particular rename is to switch away from
using the term "Array" which implies a regular, indexable layout which
isn't the case. We also want to have a strongly implied relationship
between CoglAttributes and CoglAttributeBuffers.
To help catch accidental changes to the size of public structs that can
be allocated on the stack this patch adds compile time checks that our
struct sizes haven't changed.
This adds an experimental CoglEuler data type and the following new
functions:
cogl_euler_init
cogl_euler_init_from_matrix
cogl_euler_init_from_quaternion
cogl_euler_equal
cogl_euler_copy
cogl_euler_free
cogl_quaternion_init_from_euler
Since this is experimental API you need to define
COGL_ENABLE_EXPERIMENTAL_API before including cogl.h
This adds an experimental quaternion utility API. It's not yet fully
documented but it's complete enough that people can start to experiment
with using it. It adds the following functions:
cogl_quaternion_init_identity
cogl_quaternion_init
cogl_quaternion_init_from_angle_vector
cogl_quaternion_init_from_array
cogl_quaternion_init_from_x_rotation
cogl_quaternion_init_from_y_rotation
cogl_quaternion_init_from_z_rotation
cogl_quaternion_equal
cogl_quaternion_copy
cogl_quaternion_free
cogl_quaternion_get_rotation_angle
cogl_quaternion_get_rotation_axis
cogl_quaternion_normalize
cogl_quaternion_dot_product
cogl_quaternion_invert
cogl_quaternion_multiply
cogl_quaternion_pow
cogl_quaternion_slerp
cogl_quaternion_nlerp
cogl_quaternion_squad
cogl_get_static_identity_quaternion
cogl_get_static_zero_quaternion
Since it's experimental API you'll need to define
COGL_ENABLE_EXPERIMENTAL_API before including cogl.h.
cogl-pango is conceptually a separate library so it doesn't seem
appropriate to bundle the headers with all the other cogl headers. Also
in-tree the headers live in a cogl-pango directory so if we want
examples that can include cogl-pango consistently when built in or out
of tree using the convention #include <cogl-pango/cogl-pango.h> makes
that easy.
This adds a compatibility cogl/cogl-pango.h header that's will redirect
to cogl-pango/cogl-pango.h with a warning, or result in an error if
COGL_ENABLE_EXPERIMENTAL_2_0_API is defined.
When freeing a framebuffer stack it's possible to have entries with NULL
draw or read buffers so we should check that before calling
cogl_onscreen/offscreen_free. This fixes a crash with the wayland
backend when running conformance tests such as cogl-test-object which
never push a framebuffer.
To support toolkits targeting wayland and using Cogl we allow toolkits
to be responsible for connecting to a wayland display and asking Cogl to
use the toolkit owned display and compositor object. Note: eventually
the plan is that wayland will allow retrospective querying of objects so
we won't need the foreign compositor API when Cogl can simply query it
from the foreign display.
The EGL API doesn't provide for a way to explicitly select a platform
when the driver can support multiple. Mesa allows selection using an
EGL_PLATFORM environment variable though so we set that to "wayland"
when we know that's what we want.
Some places were using COGL_HAS_WIN32 but the only macro defined is
COGL_HAS_WIN32_SUPPORT. The similar macros such as COGL_HAS_XLIB are
only defined for compatibility with existing code but COGL_HAS_WIN32
was never defined so there's no need to support it.
One of the places was including the non-existant cogl-win32.h. This
has been removed because the file only temporarily existed during
development of the backend.
In update_primitive_attributes it tries to fill in an array of
pointers with a NULL terminator. However it was only allocating enough
space for a pointer for each of the attributes plus one byte instead
of plus enough bytes for another pointer.
Thomas Wood found this bug with static analysis.
All of the winsys backends didn't handle cleaning up the CoglOnscreen
properly so that they would assert in cogl_onscreen_free because the
winsys pointer is never freed. They also didn't cope if deinit is
called before init (which will be the case if an onscreen is created
and freed without being allocated).
When SetPixelFormat fails, the DC would get released but none of the
other resources would be freed. This patch makes it call
_cogl_winsys_onscreen_deinit on failure to clean up all of the
resources. The patch looks big because it moves the onscreen_deinit
and onscreen_bind functions.
Some of the virtual functions in CoglWinsysVtable only need to be
implemented for specific backends or when a specific feature is
advertised. This splits the vtable struct into two commented sections
marking which are optional and which are required. Wherever an
optional function is used there is now a g_return_if_fail to ensure
there is an implementation.
Wayland now supports integration via standard eglSurfaces which makes it
possible to share more code with other EGL platforms. (though at some
point cogl-winsys-egl.c really needs to gain a more formal
CoglEGLPlatform abstraction so we can rein back on the amount of #ifdefs
we have.)
This removes all the remnants from being able to build Cogl standalone
while it was part of the Clutter repository. Now that Cogl has been
split out then standalone builds are the only option.
We now install cogl-pango-1.0 and cogl-pango-2.0 pkg-config files that
applications should optionally depend on if they want to use the
cogl_pango API.
If a foreign xid has been set on a CoglOnscreen then
cogl_onscreen_x11_get_window_xid doesn't need to defer to the winsys to
get the underlying window xid. This also means it's possible to read
back the xid before the framebuffer is allocated which fixes a crash in
the x11-foreign example app.
Ideally we wouldn't have any private symbols exported, but for now there
are some APIs that coglpango needs access to that aren't public so we
have ensure they are exported. The aim is to get rid of this need at
some point.
When comparing the wrap modes of two pipeline layers it now considers
COGL_WRAP_MODE_AUTOMATIC to be equivalent to CLAMP_TO_EDGE. By the
time the pipeline is in the journal, the upper primitive code is
expected to have overridden this wrap mode with something else if it
wants any other behaviour. This is important for getting text to batch
together with textures because the text explicitly sets the wrap mode
to CLAMP_TO_EDGE on its pipeline.
This adds cogl_atlas_texture_* functions to register a callback that
will get invoked whenever any of the CoglAtlas's the textures use get
reorganized. The callback is global and is not tied to any particular
atlas texture.
This adds a new function called _cogl_atlas_texture_new_with_size. The
old new_from_bitmap function now just calls this and updates the
texture with the data.
This extends cogl_onscreen_x11_set_foreign_xid to take a callback to a
function that details the event mask the Cogl requires the application
to select on foreign windows. This is required because Cogl, for
example, needs to track size changes of a window and may also in the
future want other notifications such as map/unmap.
Most applications wont need to use the foreign xwindow apis, but those
that do are required to pass a valid callback and update the event mask
of their window according to Cogl's requirements.
This adds Cogl API to show and hide onscreen framebuffers. We don't want
to go too far down the road of abstracting window system APIs with Cogl
since that would be out of its scope but the previous idea that we would
automatically map framebuffers on allocation except for those made from
foreign windows wasn't good enough. The problem is that we don't want to
make Clutter always create stages from foreign windows but with the
automatic map semantics then Clutter doesn't get an opportunity to
select for all the events it requires before mapping. This meant that we
wouldn't be delivered a mouse enter event for windows mapped underneath
the cursor which would break Clutters handling of button press events.
When building on windows for example we need to ensure we pass
-no-undefined to the linker. Although we were substituting a
COGL_EXTRA_LDFLAGS variable from our configure.ac we forgot to
reference that when linking cogl.
Until Cogl gains native win32/OSX support this remove the osx and win32
winsys files and instead we'll just rely on the stub-winsys.c to handle
these platforms. Since the only thing the platform specific files were
providing anyway was a get_proc_address function; it was trivial to
simply update the clutter backend code to handle this directly for now.
This is a workaround for a bug on OSX for some radeon hardware that
we can't verify and the referenced bug link is no longer valid.
If this is really still a problem then a new bug should be opened and we
can look at putting the fix in some more appropriate place than
cogl-gl.c
For now we are going for the semantics that when a CoglOnscreen is first
allocated then it will automatically be mapped. This is for convenience
and if you don't want that behaviour then it is possible to instead
create an Onscreen from a foreign X window and in that case it wont be
mapped automatically.
This approach means that Cogl doesn't need onscreen_map/unmap functions
but it's possible we'll decide later that we can't avoid adding such
functions and we'll have to change these semantics.
This allows more detailed control over the driver and winsys features
that Cogl should have. Cogl is designed so it can support multiple
window systems simultaneously so we have enable/disable options for
the drivers (gl vs gles1 vs gles2) and options for the individual window
systems; currently glx and egl. Egl is broken down into an option
for each platform.
The GDL API is used for example on intel ce4100 (aka Sodaville) based
systems as a way to allocate memory that can be composited using the
platforms overlay hardware. This updates the Cogl EGL winsys and the
support in Clutter so we can continue to support these platforms.
So that we can dynamically select what winsys backend to use at runtime
we need to have some indirection to how code accesses the winsys instead
of simply calling _cogl_winsys* functions that would collide if we
wanted to compile more than one backend into Cogl.
This moves the GLX specific code from cogl-texture-pixmap-x11.c into
cogl-winsys-glx.c. If we want the winsys components to by dynamically
loadable then we can't have GLX code scattered outside of
cogl-winsys-glx.c. This also sets us up for supporting the
EGL_texture_from_pixmap extension which is almost identical to the
GLX_texture_from_pixmap extension.
As was recently done for the GLX window system code, this commit moves
the EGL window system code down from the Clutter backend code into a
Cogl winsys.
Note: currently the cogl/configure.ac is hard coded to only build the GLX
winsys so currently this is only available when building Cogl as part
of Clutter.
The "DRM_SURFACELESS" EGL platform was invented when we were adding the
wayland backend to Clutter but in the end we added a dedicated backend
instead of extending the EGL backend so actually the platform name isn't
used.
Commit b061f737 moved _cogl_winsys_has_feature to the common winsys
code so there's no need to define it in the stub winsys any more. This
was breaking builds for backends using the stub winsys.
The comparison for finding onscreen framebuffers in
find_onscreen_for_xid had a small thinko so that it would ignore
framebuffers when the negation of the type is onscreen. This ends up
doing the right thing anyway because the onscreen type has the value 0
and the offscreen type has the value 1 but presumably it would fail if
we ever added any other framebuffer types.
The code for _cogl_winsys_has_feature will be identical in all of the
winsys backends for the time being, so it seems to make sense to have
it in the common cogl-winsys.c file.
Previously the mask of available winsys features was stored in a
CoglBitmask. That isn't the ideal type to use for this because it is
intended for a growable array of bits so it can allocate extra memory
if there are more than 31 flags set. For the winsys feature flags the
highest used bit is known at compile time so it makes sense to
allocate a fixed array instead. This is conceptually similar to the
CoglDebugFlags which are stored in an array of integers with macros to
test a bit in the array. This moves the macros used for CoglDebugFlags
to cogl-flags.h and makes them more generic so they can be shared with
CoglContext.
Instead of having cogl_renderer_xlib_add_filter and friends there is
now cogl_renderer_add_native_filter which can be used regardless of
the backend. The callback function for the filter now just takes a
void pointer instead of an XEvent pointer which should be interpreted
differently depending on the backend. For example, on Xlib it would
still be an XEvent but on Windows it could be a MSG. This simplifies
the code somewhat because the _cogl_xlib_add_filter no longer needs to
have its own filter list when a stub renderer is used because there is
always a renderer available.
cogl_renderer_xlib_handle_event has also been renamed to
cogl_renderer_handle_native_event. This just forwards the event on to
all of the listeners. The backend renderer is expected to register its
own event filter if it wants to process the events in some way.
Older drivers for PowerVR SGX hardware have the vendor-specific
GL_IMG_TEXTURE_NPOT extension instead of the
functionally-equivalent GL_OES_TEXTURE_NPOT extension.
We need to guard the usage of symbols related to the
GLX_INTEL_swap_event extension, to avoid breaking on platforms and/or
versions of Mesa that do not expose that extension.
It's generally useful to be able to query the width and height of a
framebuffer and we expect to need this in Clutter when we move the
eglnative backend code into Cogl since Clutter will need to read back
the fixed size of the framebuffer when realizing the stage.
This backend hasn't been used for years now and so because it is
untested code and almost certainly doesn't work any more it would be a
burdon to continue trying to maintain it. Considering that we are now
looking at moving OpenGL window system integration code down from
Clutter backends into Cogl that will be easier if we don't have to
consider this backend.
This adds an autogen.sh, configure.ac and build/autotool files etc under
clutter/cogl and makes some corresponding Makefile.am changes that make
it possible to build and install Cogl as a standalone library.
Some notable things about this are:
A standalone installation of Cogl installs 3 pkg-config files;
cogl-1.0.pc, cogl-gl-1.0.pc and cogl-2.0.pc. The second is only for
compatibility with what clutter installed though I'm not sure that
anything uses it so maybe we could remove it. cogl-1.0.pc is what
Clutter would use if it were updated to build against a standalone cogl
library. cogl-2.0.pc is what you would use if you were writing a
standalone Cogl application.
A standalone installation results in two libraries currently, libcogl.so
and libcogl-pango.so. Notably we don't include a major number in the
sonames because libcogl supports two major API versions; 1.x as used by
Clutter and the experimental 2.x API for standalone applications.
Parallel installation of later versions e.g. 3.x and beyond will be
supportable either with new sonames or if we can maintain ABI then we'll
continue to share libcogl.so.
The headers are similarly not installed into a directory with a major
version number since the same headers are shared to export the 1.x and
2.x APIs (The only difference is that cogl-2.0.pc ensures that
-DCOGL_ENABLE_EXPERIMENTAL_2_0_API is used). Parallel installation of
later versions is not precluded though since we can either continue
sharing or later add a major version suffix.
This migrates all the GLX window system code down from the Clutter
backend code into a Cogl winsys. Moving OpenGL window system binding
code down from Clutter into Cogl is the biggest blocker to having Cogl
become a standalone 3D graphics library, so this is an important step in
that direction.
As part of the process of splitting Cogl out as a standalone graphics
API we need to introduce some API concepts that will allow us to
initialize a new CoglContext when Clutter isn't there to handle that for
us...
The new objects roughly in the order that they are (optionally) involved
in constructing a context are: CoglRenderer, CoglOnscreenTemplate,
CoglSwapChain and CoglDisplay.
Conceptually a CoglRenderer represents a means for rendering. Cogl
supports rendering via OpenGL or OpenGL ES 1/2.0 and those APIs are
accessed through a number of different windowing APIs such as GLX, EGL,
SDL or WGL and more. Potentially in the future Cogl could render using
D3D or even by using libdrm and directly banging the hardware. All these
choices are wrapped up in the configuration of a CoglRenderer.
Conceptually a CoglDisplay represents a display pipeline for a renderer.
Although Cogl doesn't aim to provide a detailed abstraction of display
hardware, on some platforms we can give control over multiple display
planes (On TV platforms for instance video content may be on one plane
and 3D would be on another so a CoglDisplay lets you select the plane
up-front.)
Another aspect of CoglDisplay is that it lets us negotiate a display
pipeline that best supports the type of CoglOnscreen framebuffers we are
planning to create. For instance if you want transparent CoglOnscreen
framebuffers then we have to be sure the display pipeline wont discard
the alpha component of your framebuffers. Or if you want to use
double/tripple buffering that requires support from the display
pipeline.
CoglOnscreenTemplate and CoglSwapChain are how we describe our default
CoglOnscreen framebuffer configuration which can affect the
configuration of the display pipeline.
The default/simple way we expect most CoglContexts to be constructed
will be via something like:
if (!cogl_context_new (NULL, &error))
g_error ("Failed to construct a CoglContext: %s", error->message);
Where that NULL is for an optional "display" parameter and NULL says to
Cogl "please just try to do something sensible".
If you want some more control though you can manually construct a
CoglDisplay something like:
display = cogl_display_new (NULL, NULL);
cogl_gdl_display_set_plane (display, plane);
if (!cogl_display_setup (display, &error))
g_error ("Failed to setup a CoglDisplay: %s", error->message);
And in a similar fashion to cogl_context_new() you can optionally pass
a NULL "renderer" and/or a NULL "onscreen template" so Cogl will try to
just do something sensible.
If you need to change the CoglOnscreen defaults you can provide a
template something like:
chain = cogl_swap_chain_new ();
cogl_swap_chain_set_has_alpha (chain, TRUE);
cogl_swap_chain_set_length (chain, 3);
onscreen_template = cogl_onscreen_template_new (chain);
cogl_onscreen_template_set_pixel_format (onscreen_template,
COGL_PIXEL_FORMAT_RGB565);
display = cogl_display_new (NULL, onscreen_template);
if (!cogl_display_setup (display, &error))
g_error ("Failed to setup a CoglDisplay: %s", error->message);
This tries to make the naming style of files under cogl/winsys/
consistent with other cogl source files. In particular private header
files didn't have a '-private' infix.