There is a new internal Cogl function called _cogl_check_driver_valid
which looks at the value of the GL_VERSION string to determine whether
the driver is supported. Clutter now calls this after the stage is
realized. If it fails then the stage is marked as unrealized and a
warning is shown.
_cogl_features_init now also checks the version number before getting
the function pointers for glBlendFuncSeparate and
glBlendEquationSeparate. It is not safe to just check for the presence
of the functions because some drivers may define the function without
fully implementing the spec.
The GLES version of _cogl_check_driver_valid just always returns TRUE
because there are no version requirements yet.
Eventually the function could also check for mandatory extensions if
there were any.
http://bugzilla.openedhand.com/show_bug.cgi?id=1875
Because Cogl defines the origin of viewport and window coordinates to be
top-left it always needs to know the size of the current window so that Cogl
window/viewport coordinates can be transformed into OpenGL coordinates.
This also fixes cogl_read_pixels to use the current draw buffer height
instead of the viewport height to determine the OpenGL y coordinate to use
for glReadPixels.
The only backend that tried to implement offscreen stages was the GLX backend
and even this has apparently be broken for some time without anyone noticing.
The property still remains and since the property already clearly states that
it may not work I don't expect anyone to notice.
This simplifies quite a bit of the GLX code which is very desireable from the
POV that we want to start migrating window system code down to Cogl and the
simpler the code is the more straight forward this work will be.
In the future when Cogl has a nicely designed API for framebuffer objects then
re-implementing offscreen stages cleanly for *all* backends should be quite
straightforward.
When computing the pixels value of a ClutterUnits value we should
be caching the value to avoid recomputing for every call of
clutter_units_to_pixels(). We already have a flag telling us to
return the cached value, but we miss the mechanism to evict the
cache whenever the Backend settings affecting the conversion, that
is default font and resolution, change.
In order to implement the eviction we can use a "serial"; the
Backend will have an internal serial field which we retrieve and
put inside the ClutterUnits structure (we split one of the two
64 bit padding fields into two 32 bit fields to maintain ABI); every
time we call clutter_units_to_pixels() we compare the units serial
with that of the Backend; if they match and pixels_set is set to
TRUE then we just return the stored pixels value. If the serials
do not match then we unset the pixels_set flag and recompute the
pixels value.
We can verify this by adding a simple test unit checking that
by changing the resolution of ClutterBackend we get different
pixel values for 1 em.
http://bugzilla.openedhand.com/show_bug.cgi?id=1843
Instead of using ClutterActor for the base class of the Stage
implementation we should extend the StageWindow interface with
the required bits (geometry, realization) and use a simple object
class.
This require a wee bit of changes across Backend, Stage and
StageWindow, even though it's mostly re-shuffling.
First of all, StageWindow should get new virtual functions:
* geometry:
- resize()
- get_geometry()
* realization
- realize()
- unrealize()
This covers all the bits that we use from ClutterActor currently
inside the stage implementations.
The ClutterBackend::create_stage() virtual function should create
a StageWindow, and not an Actor (it should always have been; the
fact that it returned an Actor was a leak of the black magic going
on underneath). Since we never guaranteed ABI compatibility for
the Backend class, this is not a problem.
Internally to ClutterStage we can finally drop the shenanigans of
setting/unsetting actor flags on the implementation: if the realization
succeeds, for instance, we set the REALIZED flag on the Stage and
we're done.
As an initial proof of concept, the X11 and GLX stage implementations
have been ported to the New World Order(tm) and show no regressions.
The StageManager singleton instance is already kept around
by the clutter_stage_manager_get_default() function; there is
no need to have it inside the main Clutter context as well.
The clutter_context_get_default() function is private, but shared
across Clutter. For this reason, it should be prefixed by '_' so
that the symbol is hidden from the shared object.
This is the another step into abstracting the backend operations
that are currently spread all across the board back into the
backend implementations where they belong.
The GL context creation, for instance, is demanded to the stage
realization which makes it a critical path for every operation
that is GL-context bound. This usually does not make any difference
since we realize the default stage, but at some point we might
start looking into avoiding the default stage realization in order
to make the Clutter startup faster.
It also makes the code maintainable because every part is self
contained and can be reworked with the minimum amount of pain.
This commit reverts part of commit 5bcde25c - specifically the
part that forced a realization of the stage if we are ensuring
the GL context with it. This makes Clutter behave like it did
prior to commit 5bcde25c: if we are asked to ensure the GL context
with an unrealized stage we simply pass NULL to the backend
implementation.
The fix for bug 1138 broke multi-stage support on GLX, causing
X11 to segfault with the following stack trace:
Backtrace:
0: /usr/X11R6/bin/X(xf86SigHandler+0x7e) [0x80c91fe]
1: [0xb7eea400]
2: /usr/lib/xorg/modules/extensions//libglx.so [0xb7ae880c]
3: /usr/lib/xorg/modules/extensions//libglx.so [0xb7aec0d6]
4: /usr/X11R6/bin/X [0x8154c24]
5: /usr/X11R6/bin/X(Dispatch+0x314) [0x808de54]
6: /usr/X11R6/bin/X(main+0x4b5) [0x8074795]
7: /lib/i686/cmov/libc.so.6(__libc_start_main+0xe5) [0xb7c75775]
8: /usr/X11R6/bin/X(FontFileCompleteXLFD+0x21d) [0x8073a81]
which I can only track down to clutter_backend_glx_ensure_current()
being passed a NULL stage -- something that happens when a stage
is not correct realized. That should lead to a glXMakeCurrent(None)
and not to a segmentation fault, though.
Currently, the conversion from em to units is done by using the
default font name inside the backend. For actors using their own
font/text layout we need a way to specify the font name along
with the quantity we wish to transform.
With the recent change to internal floating point values, ClutterUnit
has become a redundant type, defined to be a float. All integer entry
points are being internally converted to floating point values to be
passed to the GL pipeline with the least amount of conversion.
ClutterUnit is thus exposed as just a "pixel with fractionary bits",
and not -- as users might think -- as generic, resolution and device
independent units. not that it was the case, but a definitive amount
of people was convinced it did provide this "feature", and was flummoxed
about the mere existence of this type.
So, having ClutterUnit exposed in the public API doubles the entry
points and has the following disadvantages:
- we have to maintain twice the amount of entry points in ClutterActor
- we still do an integer-to-float implicit conversion
- we introduce a weird impedance between pixels and "pixels with
fractionary bits"
- language bindings will have to choose what to bind, and resort
to manually overriding the API
+ *except* for language bindings based on GObject-Introspection, as
they cannot do manual overrides, thus will replicate the entire
set of entry points
For these reason, we should coalesces every Actor entry point for
pixels and for ClutterUnit into a single entry point taking a float,
like:
void clutter_actor_set_x (ClutterActor *self,
gfloat x);
void clutter_actor_get_size (ClutterActor *self,
gfloat *width,
gfloat *height);
gfloat clutter_actor_get_height (ClutterActor *self);
etc.
The issues I have identified are:
- we'll have a two cases of compiler warnings:
- printf() format of the return values from %d to %f
- clutter_actor_get_size() taking floats instead of unsigned ints
- we'll have a problem with varargs when passing an integer instead
of a floating point value, except on 64bit platforms where the
size of a float is the same as the size of an int
To be clear: the *intent* of the API should not change -- we still use
pixels everywhere -- but:
- we remove ambiguity in the API with regard to pixels and units
- we remove entry points we get to maintain for the whole 1.0
version of the API
- we make things simpler to bind for both manual language bindings
and automatic (gobject-introspection based) ones
- we have the simplest API possible while still exposing the
capabilities of the underlying GL implementation
The font options accessors in ClutterBackend only deal with const
cairo_font_options_t values, since:
- set_font_options() will copy the font options
- get_font_options() will return a pointer to the internal
font options
Not using const in these cases makes the API confusing and might lead
to erroneous calls to cairo_font_options_destroy().
Bug 1442 - multistage, same-window resize events invalidate stage
When ensuring that the GL context is attached to the correct
ClutterStage we need to set the SYNC_MATRICES flag on the stage
itself. This is needed in case the size of the new stage does
not match the size of the old -- thus requiring a call to
glViewport() when the paint cycle starts.
Add annotations such as (transfer-none) (out) (element-type ClutterActor),
and so forth to the doc comments as appropriate.
The annotations added here are a combination of the annotations previously
in gir-repository for Clutter and annotations found in a review of all
return values with that were being parsed with a transfer of "full".
http://bugzilla.openedhand.com/show_bug.cgi?id=1452
Signed-off-by: Emmanuele Bassi <ebassi@linux.intel.com>
Instead of recomputing the number of units needed to fit in
an em each time clutter_units_em() is called, we can store this
value into the default Backend along with the resolution and
font name. The value should also be updated each time the
resolution and font are changed, to keep it up to date.
This is the result of running a number of sed and perl scripts over the code to
do 90% of the work in converting from 16.16 fixed to single precision floating
point.
Note: A pristine cogl-fixed.c has been maintained as a standalone utility API
so that applications may still take advantage of fixed point if they
desire for certain optimisations where lower precision may be acceptable.
Note: no API changes were made in Clutter, only in Cogl.
Overview of changes:
- Within clutter/* all usage of the COGL_FIXED_ macros have been changed to use
the CLUTTER_FIXED_ macros.
- Within cogl/* all usage of the COGL_FIXED_ macros have been completly stripped
and expanded into code that works with single precision floats instead.
- Uses of cogl_fixed_* have been replaced with single precision math.h
alternatives.
- Uses of COGL_ANGLE_* and cogl_angle_* have been replaced so we use a float for
angles and math.h replacements.
Continuation of the fix in commit 00a3c69868.
Instead of using a separate flag for the resize process, just
delay the setting of the CLUTTER_ACTOR_SYNC_MATRICES flag on the
stage to the point when we receive a ConfigureNotify event from
X11.
This commit will break the stage embedding into other toolkits.
When calling clutter_backend_get_font_name(), if no default font
name has previously been set, we just set the default and return
a pointer to it - like we do for the font options.
The default backend stores some of the global defaults, like the
font options, text resolution, double click settings. It should also
store the default font name, to allow various text-based actors to
share the same settings.
When the font name changes, the ::font-changed signal is emitted,
to allow actors to pick up the change.
The ClutterBackend instance at the moment lacks the ability to
notify runtime changes of the font options and the resolution.
For this reason, this commit adds a ::resolution-changed and a
::font-changed signals to the Backend class.
The ::resolution-changed signal is emitted when set_resolution()
is called with a different DPI; ::font-changed is emitted when the
cairo_font_options_t* changes from the default.
Bug 1209 - Move fixed point API in COGL
* clutter/cogl/cogl-fixed.h:
* clutter/cogl/cogl.h.in:
* clutter/cogl/common/Makefile.am:
* clutter/cogl/common/cogl-fixed.c: Add fixed point API, modelled
after the ClutterFixed. The CoglFixed API supercedes the ClutterFixed
one and avoids the dependency of COGL on Clutter's own API.
* clutter/cogl/common/cogl-clip-stack.c:
* clutter/cogl/common/cogl-primitives.c:
* clutter/cogl/common/cogl-primitives.h: Update internal usage of
ClutterFixed to CoglFixed.
* clutter/cogl/gl/Makefile.am:
* clutter/cogl/gl/cogl-primitives.c:
* clutter/cogl/gl/cogl-texture.c:
* clutter/cogl/gl/cogl.c: Ditto, in the GL implementation of the
COGL API.
* clutter/cogl/gles/Makefile.am:
* clutter/cogl/gles/cogl-fbo.c:
* clutter/cogl/gles/cogl-gles2-wrapper.c:
* clutter/cogl/gles/cogl-primitives.c:
* clutter/cogl/gles/cogl-texture.c:
* clutter/cogl/gles/cogl.c: Ditto, in the GLES implementation of
the COGL API.
* clutter/pango/pangoclutter-glyph-cache.c:
* clutter/pango/pangoclutter-glyph-cache.h: Ditto, in the Pango
renderer glyphs cache.
* clutter/clutter-fixed.c:
* clutter/clutter-fixed.h: ClutterFixed and related API becomes
a simple transition API for bindings and public Clutter API.
* clutter/clutter-actor.c:
* clutter/clutter-alpha.c:
* clutter/clutter-backend.c:
* clutter/clutter-behaviour-depth.c:
* clutter/clutter-behaviour-ellipse.c:
* clutter/clutter-behaviour-path.c:
* clutter/clutter-behaviour-rotate.c:
* clutter/clutter-behaviour-scale.c:
* clutter/clutter-clone-texture.c:
* clutter/clutter-color.c:
* clutter/clutter-entry.c:
* clutter/clutter-stage.c:
* clutter/clutter-texture.c:
* clutter/clutter-timeline.c:
* clutter/clutter-units.h: Move from the internal usage of
ClutterFixed to CoglFixed.
* doc/reference/clutter/clutter-sections.txt:
* doc/reference/cogl/cogl-docs.sgml:
* doc/reference/cogl/cogl-sections.txt: Update the documentation.
* tests/test-cogl-tex-tile.c:
* tests/test-project.c: Fix tests after the API change
* README: Add release notes.
* clutter/clutter-actor.c:
(clutter_actor_set_min_width),
(clutter_actor_set_min_height),
(clutter_actor_set_natural_width),
(clutter_actor_set_natural_height): Ignore any override of the
minimum and natural size of the stage on backends that only
support static stages.
* clutter/clutter-stage.c (clutter_stage_allocate): Use the
preferred size of the ClutterStage implementation instead of
the display size.
* clutter/clutter-backend.[ch]: Remove get_display_size() and
clutter_backend_get_display_size().
* clutter/eglnative/clutter-backend-egl.c:
* clutter/fruity/clutter-backend-fruity.c:
* clutter/osx/clutter-backend-osx.c:
* clutter/sdl/clutter-backend-sdl.c:
* clutter/win32/clutter-backend-win32.c:
* clutter/x11/clutter-backend-x11.c: Remove get_display_size()
implementations.
* clutter/clutter-backend.c:
(clutter_backend_get_display_size): Provide a fallback for
backends not implementing get_display_size().
* clutter/clutter-stage.c:
(clutter_stage_allocate): Add debug messages.
* clutter/sdl/clutter-backend-sdl.c:
(clutter_backend_sdl_get_display_size),
(clutter_backend_sdl_class_init): Implement get_display_size()
on the SDL backend.
* clutter/clutter-backend.h:
* clutter/clutter-backend.c:
(clutter_backend_get_display_size): Add a function for getting the
display size out of the backend.
* clutter/clutter-stage.c:
(clutter_stage_allocate): When allocating on a backend with a
static stage, we simply ignore the passed box and override it with
the size of the display.
* clutter/eglnative/clutter-backend-egl.c:
(clutter_backend_egl_get_display_size),
(clutter_backend_egl_class_init): Implement get_display_size() by
returning the size of the EGL surface.
* clutter/fruity/clutter-backend-fruity.c:
(clutter_backend_egl_get_display_size),
(clutter_backend_egl_class_init): Ditto as above.
* clutter/x11/clutter-backend-x11.c:
(clutter_backend_x11_get_display_size),
(clutter_backend_x11_class_init): Implement get_display_size() by
returning the DisplayWidth and DisplayHeight of the current
screen.
Bug #919 - Replacement pango renderer (Neil Roberts)
* clutter/clutter-backend.h:
* clutter/clutter-backend.c:
(clutter_backend_set_font_options),
(clutter_backend_get_font_options): Add the ability to set
the cairo_font_options_t* for the backend at construction
time, so that backend implementations can have their own
options.
* clutter/clutter-color.c: Include pango/pango-attributes.h
for the pango_color_parse() function.
* clutter/clutter-label.c:
(clutter_label_ensure_layout),
(clutter_label_init), (clutter_label_set_text),
(clutter_label_set_font_name), (clutter_label_set_ellipsize),
(clutter_label_set_use_markup): Ensure that the cache is
always primed when the Label changes; this makes sure that
the cache is rebuilt outside the paint run, which should
make the painting perform better especially on embedded
devices.
* clutter/clutter-entry.c:
(clutter_entry_ensure_layout),
(clutter_entry_init), (clutter_entry_set_text),
(clutter_entry_set_font_name): Ditto as above.
* clutter/clutter-private.h:
* clutter/clutter-main.[ch]: Create the font-map inside the
main context; add two new functions:
clutter_clear_glyph_cache()
clutter_set_use_mipmapped_text()
that control the glyphs cache.
* clutter/pango/Makefile.am:
* clutter/pango/pangoclutter-fontmap.c:
* clutter/pango/pangoclutter-private.h:
* clutter/pango/pangoclutter-render.c:
* clutter/pango/pangoclutter.h: Rewrite the Pango renderer
using a PangoCairo context and saving the glyphs inside a
more efficient cache.
* configure.ac: Depend on pangocairo instead of pangoft2.
* clutter/clutter-backend.c:
(_clutter_backend_create_stage): Call _clutter_stage_set_window()
ourselves, thus removing yet another action that backends must
implement and might get wrong; also cuts a backend-agnostic piece
of code duplication.
* clutter/eglnative/clutter-backend-egl.c:
(clutter_backend_egl_create_stage): Update the EGL native backend.
* clutter/eglx/clutter-backend-egl.c:
(clutter_backend_egl_create_stage): Update the EGLX backend.
* clutter/fruity/clutter-backend-fruity.c:
(clutter_backend_egl_create_stage): Update the fruity backend
* clutter/glx/clutter-backend-glx.c:
(clutter_backend_glx_create_stage): Update the GLX backend.
* clutter/sdl/clutter-backend-sdl.c:
(clutter_backend_sdl_create_stage): Update the SDL backend.
* HACKING.backends: Update the ::create_stage() description.
* clutter/clutter-backend.c: Add more debug messages
* clutter/clutter-stage.h:
* clutter/clutter-stage.c:
(clutter_stage_is_default): Add a function to check if the
stage is the default one.
* clutter/glx/clutter-backend-glx.c:
* clutter/glx/clutter-stage-glx.c:
* clutter/x11/clutter-stage-x11.c: Keep the stage wrapper
and implementation flags in sync, to ensure that the GL
context is always set.
Bug #864 - Allow instantiating and subclassing of ClutterStage
* clutter/Makefile.am: Add clutter-stage-window.[ch]
* clutter/clutter-stage-manager.c:
(_clutter_stage_manager_remove_stage): Do not warn if removing
a stage we don't manage, as we might be invoked multiple times
during a ClutterState dispose sequence.
* clutter/clutter-actor.c:
* clutter/clutter-backend.[ch]:
* clutter/clutter-main.c:
* clutter/clutter-private.h:
* clutter/clutter-stage.[ch]: Make ClutterStage a proxy actor,
with a private actor implementing the ClutterStageWindow
interface for handling the per-backend realization, painting
and unrealization, plus all the windowing system abstraction.
* clutter/x11/clutter-event-x11.c:
* clutter/x11/clutter-stage-x11.[ch]: Port the X11 backend
to the new backend and stage API and semantics.
* clutter/glx/clutter-backend-glx.c:
* clutter/glx/clutter-stage-glx.c: Port the GLX backend to
the new backend and stage API and semantics.
* clutter/eglx/clutter-backend-egl.[ch]:
* clutter/eglx/clutter-stage-egl.[ch]: Port the EGLX backend
to the new backend and stage API and semantics (untested).
* tests/test-multistage.c (on_button_press): Rename
clutter_stage_create_new() to clutter_stage_new().
* clutter/clutter-backend.c:
* clutter/glx/clutter-backend-glx.c:
* clutter/glx/clutter-stage-glx.c:
Allow NULL to be passed to _clutter_backend_ensure_context
which essentially clears GL context. This is hooked into stage
unrealisation. Isn't yet quite bulletproof.
Fixes issues with gtk-embed crasher (thanks to Neil).
* clutter/clutter-backend.[ch]: Add clutter_backend_set_resolution()
and clutter_backend_get_resolution(); backends should use the former
to set the resolution of the display when initialising, while actors
should use the latter when sizing themselves depending on the
resolution or the font size.
* clutter/glx/clutter-backend-glx.c: Set the resolution as 96 dpi
as a default and query the X server when opening the display.
* clutter/clutter-entry.c: Drop the hardcoded dpi value and use
clutter_backend_get_resolution() to compute the default size.
* clutter/clutter-backend.c:
* clutter/clutter-backend.h:
* clutter/glx/clutter-stage-glx.c:
* clutter/glx/clutter-backend-glx.c:
Fix up rendering pipeline removing clutter_backend_XXX_stage_paint
and adding clutter_backend_XXX_redraw instead. Duplicates less
code in backends, avoids clutter_actor_paint() getting called
before stage is set up (viewport wise) and unbreaks things like
picking.
* clutter/clutter-actor.c:
* clutter/clutter-actor.h:
* clutter/clutter-main.c:
* clutter/clutter-private.h:
* clutter/clutter-stage.c: (clutter_stage_get_actor_at_pos):
Redo picking functionality a different way (via color indexing)
as to provide more flexibility, possibly speed and more likely
work with GL/ES (doesn't currently however - not sure why).
* clutter/clutter-group.c:
Add groups own 'pick' method.
* clutter/cogl/cogl.h:
* clutter/cogl/gl/cogl.c:
* clutter/cogl/gles/cogl.c:
Move clipping funtionality into cogl.
* clutter/cogl/gles/cogl-defines.h:
Hack around missing BGR format in GL/ES.
* clutter/egl/clutter-backend-egl.c:
* clutter/egl/clutter-backend-egl.h:
* clutter/egl/clutter-stage-egl.c:
* clutter/sdl/clutter-backend-sdl.c:
* clutter/sdl/clutter-backend-sdl.h:
* clutter/sdl/clutter-event-sdl.c:
* clutter/sdl/clutter-stage-sdl.c:
Update backends to newer API.
Add basic mouse event translation to SDL.
* clutter/clutter-backend.c:
* clutter/clutter-backend.h:
* clutter/clutter-event.c:
* clutter/clutter-main.c:
* clutter/clutter-private.h:
* clutter/glx/clutter-backend-glx.c:
* clutter/glx/clutter-backend-glx.h:
* clutter/glx/clutter-event-glx.c:
Rejig backend event code as to simplify a little.
NOTE: This breaks non glx backends.
* tests/Makefile.am:
* tests/test-events.c:
Add a very simple event test.
* tests/test-textures.c: (main):
Add some more sizes to the test.
Add clutter_backend_get_n_screens(), which returns the number of screens
manager by the ClutterBackend, and change clutter_backend_get_screen_number()
to return the screen number of the currently used screen; this is semantically
equivalent to clutter_glx_get_default_screen(), but leaves the door open for
a "screen" abstraction in Clutter, handled by the backend. Update the GLX
and EGL backends to retrieve and set the screen_num and n_screens members of
ClutterBackend using Xlib calls.
Add functions to retrieve some of the properties of the screen used by
the backend, like its dimensions (also physical, in millimeters); the
number of screens. Also add setters and getters for the double click
time (in milliseconds) and distance.
* clutter/clutter-backend.c: Clear the event queue when
disposing the backend object; remove the initialisation
of the backend structure members...
* clutter/glx/clutter-backend-glx.c: ... and keep it here
in the backends where it belongs.
* clutter/clutter-private.h:
* clutter/clutter-backend.h: Move the backend functions
into the private header.
* clutter/glx/clutter-stage-glx.c:
* clutter/glx/clutter-event-glx.c:
* clutter/clutter-main.c:
* clutter/clutter-stage.c: Update the calls to the private
backend functions.
* clutter/clutter-backend.[ch]: Add an ::init_features
vfunc to ClutterBackend.
* clutter/clutter-private.h: Remove inclusion of backend-specific
headers; update the main context object; add the declarations for
the event queue functions.
* clutter/clutter-backend.[ch]: Add the abstract ClutterBackend
object, which holds backend-specific settings, the main stage,
and the event queue. Every backend must implement a subclass of
ClutterBackend and ClutterStage.
* clutter/clutter-feature.c: Protect the GLX specific calls
behing #ifdef HAVE_CLUTTER_GLX.
* clutter/clutter-actor.c:
* clutter/clutter-group.c:
* clutter/clutter-clone-texture.c: Include GL/gl.h
* clutter/clutter-event.[ch]: Update public API and implement the
event queue private API; hold a reference on the event objects;
move out the keysym-to-unicode table; add the new event types.
* clutter/clutter-color.h: Include clutter-fixed.h
* clutter/clutter-main.c: Update API; get the main stage
from the backend object; process the event received from the
queue; lock/unlock the main mutex if we have one; move the
initialisation process sooner in the init sequence, in order to
have the backend object when we check for options; call the
backed vfuncs in the pre/post parse hooks.
* clutter/clutter-stage.c: Make ClutterStage and abstract class,
implemented by the backends.
* clutter/clutter/glx/clutter-glx.h:
* clutter/clutter/glx/clutter-backend-glx.[ch]:
* clutter/clutter/glx/clutter-event-glx.c:
* clutter/clutter/glx/clutter-stage-glx.[ch]:
* clutter/clutter/glx/Makefile.am: Add the GLX backend.
* clutter/clutter/egl/clutter-backend-egl.[ch]:
* clutter/clutter/egl/clutter-event-egl.c:
* clutter/clutter/egl/clutter-stage-egl.[ch]:
* clutter/clutter/egl/Makefile.am: Add the stub for a EGL backend.
* examples/*.c: Update for the new API.
