This makes automake place the object files in the same subdir as the
source file. For a recursive build system as we have now, there's
no difference, but with a non-recursive build system it means that
the object files don't all end up in the toplevel directory.
The API to use remoteFx encoding has changed between master and stable 1.1
branch. This patch should fix compilation for both.
This new version adds checks for the freerdp/version.h file
Previously the option was --enable-demo-clients and the conditional was
ENABLE_DEMO_CLIENTS. They control whether or not we install the demo clients
(ie all other clients than weston-terminal and weston-info). Rename the
option and the conditional to better reflect this.
This adds a test that tries to simulate a simple game loop that would
be like this:
while (1) {
draw_something();
eglSwapBuffers();
}
In this case the test is relying on eglSwapBuffers to throttle to a
sensible frame rate.
The test then verifies that only 2 EGL buffers are used. This is done
via a new request and event in the wayland-test protocol.
Currently this causes 3 buffers to be created because the release
event generated by the swap buffers is not processed by Mesa until it
blocks for the frame complete event in the next swap buffers call, but
that is too late.
This can be fixed in Mesa by issuing a sync request after the swap
buffers and blocking on it before deciding whether to allocate a new
buffer.
The tablet-shell is unmaintained and unused. It is currently
dead-weight and a burden when we make changes to weston. Let's
drop it for now, we can pull it out of git if we find a need for it later.
If posix_fallocate is available, use it instead of ftruncate. Unlike
ftruncate, when posix_fallocate succeeds, it guarantees that you cannot
run out of disk space, when later writing to the mmap()'ed file.
With posix_fallocate, if os_create_anonymous_file() succeeds, the
program cannot get a SIGBUS later from accessing this file via mmap. If
there is insufficient disk space, the function fails and errno is set to
ENOSPC.
This is useful on systems, that limit the available buffer space by
having XDG_RUNTIME_DIR on a small tmpfs.
Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
The default can be set by passing WESTON_SHELL_CLIENT as an argument
to configure, similarly to WESTON_NATIVE_BACKEND.
Reviewed-by: Bryce Harrington <b.harrington@samsung.com>
If libdrm is available, weston-launch and launcer-util.c will support
getting the drm device and setting and dropping drm master, otherwise
we'll only support getting input devices.
This adds a window frame with a close button. Similar to the X11 backend,
The window supports dragging but not resizing.
Signed-off-by: Jason Ekstrand <jason@jlekstrand.net>
Instead of connecting to weston-launch from launcher-util, we now try to
connect to logind first. If logind provides session-devices, we use them.
If not, we fall back to the old weston-launch facility.
This adds optional libdbus integration for weston. If libdbus is available
and not disabled via --disable-dbus during weston build, we now provide
basic DBusConnection main-loop integration for weston.
The dbus.c file provides a new helper to integrate any DBusConnection
object into a wl_event_loop object. This avoids any glib/qt/..
dependencies but instead only uses the low-level libdbus library.
Note that we do not provide dummy fallbacks for dbus helpers in case
dbus-support is disabled. The reason for that is that you need dbus/dbus.h
for nearly any operation you want to do via dbus. Therefore, only the most
basic helpers which can be used independently provide a "static inline"
dummy fallback to avoid #ifdef all over the code.
The time spent loading EGL and GLES libraries from disk can be a
considerable hit in some embedded use cases. If Weston is compiled
with EGL support, the binary will depend on those libraries, even if
a software renderer is in use.
This patch splits the GL renderer into a separate loadable module,
and moves the dependency on EGL and GLES to it. The backends still
need the EGL headers for the native types and EGLint. The function
load_module() is renamed to weston_load_module() and exported, so
that it can be used by the backends.
The gl renderer interface is changed so that there is only one symbol
that needs to be dlsym()'d. This symbol contains pointers to all the
functions and data necessary to interact with the renderer. As a side
effect, this change simplifies gl-renderer.h a great deal.
The compositor uses libdrm in launcher-util.c if the drm backend is
built, but there was no explicit requirement in the build. egl brings
libdrm implicity so the build doesn't fail.
This patch adds an explicit dependency between the compositor and
libdrm if the drm backend is built, so that changes to the compositor
modules don't cause build failures.
This patch adds a feature to the DRM backend that uses libva for
encoding the screen contents in H.264. Screen recording can be
activated by pressing mod-shift-space q. A file named capture.h264
will be created in the current directory, which can be muxed into
an MP4 file with gstreamer using
gst-launch filesrc location=capture.h264 ! h264parse ! mp4mux ! \
filesink location=file.mp4
This is limitted to the DRM compositor in order to avoid a copy when
submitting the front buffer to libva. The code in vaapi-recorder.c
takes a dma_buf fd referencing it, does a colorspace conversion using
the video post processing pipeline and then uses that as input to the
encoder.
I'm sending this now so I get comments, but this is not ready for
prime time yet. I have a somewhat consistent GPU hang when using
i915 with SandyBridge. Sometimes a page flip never completes. If you
want to try this anyway and your system get stuck, you might need to
run the following:
# echo 1 > /sys/kernel/debug/dri/0/i915_wedged
After that, alt-sysrq [rv] should work.
Once that's fixed it would also be good to make the parameters used by
the encoder more flexible. For now the QP parameter is hardcoded to 0
and we have only I and P frames (no B frames), which causes the
resulting files to be very large.
Previously the configure script would silently disable the use of
accelerated cairo in the clients if cairo-gl could not be found (or
cairo-glesv2 if that was requested.) Conversely the use of cairo-gl
would be automatically enabled if it was found with no way to disable
that feature
This change adds --with-cairo which takes one of "image", "gl" or
"glesv2" (defaulting to "image"). If "gl" or "glesv2" is specified
cairo-egl is checked for as well as the specified renderer. If the check
fails then the configure process errors out.
This patch adds a configure option which will enable
user to install demo clients if desired. It is disabled
by default.
v2: Remove AC_DEFINE as it is not necesary
AC_USE_SYSTEM_EXTENSIONS enables _XOPEN_SOURCE, _GNU_SOURCE and similar
macros to expose the largest extent of functionality supported by the
underlying system. This is required since these macros are often
limiting rather than merely additive, e.g. _XOPEN_SOURCE will actually
on some systems hide declarations which are not part of the X/Open spec.
Since this goes into config.h rather than the command line, ensure all
source is consistently including config.h before anything else,
including system libraries. This doesn't need to be guarded by a
HAVE_CONFIG_H ifdef, which was only ever a hangover from the X.Org
modular transition.
Signed-off-by: Daniel Stone <daniel@fooishbar.org>
[pq: rebased and converted more files]
Whether or not a shm pool is used for resizing is now configurable at
build time (--disable-resize-optimization).
[pq: removed an unnecessary hunk from the patch]
Replace the GL renderer with the new rpi-renderer on the Raspberry Pi
backend. This makes Weston on rpi not use EGL or GL anymore, at all.
The weston_plane feature is disabled, since the rpi-renderer does the
same, but better.
Add a command line option to select the output transform. It is not a
weston.ini option for now, since the rpi backend does not read the
configuration file yet. Hopefully that will be done later with some
shared code.
Add the rpi options to 'weston --help' output.
Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
This allows users to change the assigned display profile in GNOME (using
gnome-control-center) or KDE (using colord-kde) and also allows the profiling
tools to correctly inhibit the calibration state whilst measuring the native
screen response.
Add a demo program with:
- a main surface (green)
- a Cairo-image sub-surface (red)
- a raw GLESv2 widget (triangle)
Sub-surface input region is set empty to avoid problems in toytoolkit.
If Cairo links to libGL, then we will end up with also libGLESv2 linked
to subsurfaces program, and both libs getting really used, which leads
to disaster.
Do not build subsurfaces demo, if Cairo links to libGL and cairo-egl is
usable.
The GL rendering loop is not tied to the toytoolkit or the widget, but
runs directly from its own frame callback. Therefore it runs
independent of the rest of the application. This also relies on one of
two things:
- eglSwapInterval(0) is implemented, and therefore eglSwapBuffers never
blocks indefinitely, or
- toytoolkit has a workaround, that guarantees that eglSwapBuffers will
return soon, when we force a repaint on resize.
Otherwise the demo will deadlock.
The code is separated into three sections:
1. The library component, using only EGL, GLESv2, and libwayland-client
APIs, and not aware of any toolkit details of the parent application.
This runs independently until the parent application tells otherwise.
2. The glue code: a toytoolkit application widget, who has its own
rendering machinery.
3. The application written in toytoolkit.
This patch also adds new toytoolkit interfaces:
- widget_get_wl_surface()
- widget_get_last_time()
- widget_input_region_add()
Toytoolkit applications have not had a possibility to change the input
region. The frame widget (decorations) set the input region on its own
when used, otherwise the default input region of everything has been
used. If a window does not have a frame widget, it can now use
widget_input_region_add() to set a custom input region.
These are not window methods, because a widget may lie on a different
wl_surface (sub-surface) than the window.
Changes in v3:
- replace set_commit_mode with set_sync and set_desync
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
This patch is the 6th version of the FreeRDP based compositor.
Changes from last version:
* use pixman_image_get_stride() when appropriate
* always realloc
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Otherwise, it means the X11 compositor depends on another library to
pull xcb-shm (cairo?), which is not always the case. Here I end up with:
[01:54:38.970] Failed to load module:
$prefix/lib/weston/x11-backend.so: undefined symbol: xcb_shm_id
This patch installs the three header files that define the compositor
plugin interface as well as a pkg-config file. This allows
building weston plugins outside the weston tree. We currently don't make
any guarantees about the plugin API/ABI except that within a stable
branch we won't break it.
libunwind has a dwarf parser and automatically queries the dlinfo
for location of dlopened modules. The resulting backtrace is much
better and includes stack frames in dynamically loaded modules.
krh: Originally submitted for Xorg, adapted for weston:
http://lists.x.org/archives/xorg-devel/2013-February/035493.html
Note this require libunwind at least 1.1 to get the pkg-config files.
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
By default enabled but one can disable it by passing --disable-xwayland-test
to the configure script. Also, the weston-tests-env script is trying to load
xwayland.so in either case, but it behaves resilient in the absence of that
meaning all the other tests are still going to be kicked for running.
Signed-off-by: Tiago Vignatti <tiago.vignatti@intel.com>
When cairo-gl and mesa-glu are present on the system, autoconf successfully
recognizes both. However, I was wondering why weston-screensaver was not
building since autoconf reported all dependencies were met.
Move the mesa-glu PKG_CHECK before the conditional. Additionally, remove
redundant check for enable_egl, as it is implied when GLU is 'yes.'
Signed-off-by: Joe Konno <joe.konno@intel.com>
Add a frame buffer backend using pixman to render to fbdev.
This has been tested against nouveaufb but nothing else. Much of the code
came straight from the rpi backend (and copyright has been attributed
accordingly).
The behaviour of this backend on less modern frame buffers has yet to be
tested.
The refresh rate is calculated from the frame buffer's metadata. Every frame
is finished in synchrony with the refresh rate.
Frame buffer devices are currently specified on the command line (or using
the default of /dev/fb0); udev could be used in future to enumerate them.
pixman is used for compositing, and a suitable pixman format is built from
the frame buffer's metadata. This doesn't support the full range of
frame buffer formats, but does support varying BPPs of RGBA and ARGB. That
should be enough for now.
The following are not currently supported:
• FOURCC
• Non-packed formats (interleaved, planes, etc.)
• Non-true-colour formats (monochrome, greyscale, etc.)
• Big-endian formats (with component MSBs on the right)
• Non-RGBA and non-ARGB formats
Signed-off-by: Philip Withnall <philip@tecnocode.co.uk>
The Android backend has been fairly unused, since we do not have
projects actively using it. It gets basic build testing as part of the
normal build, but runtime testing it takes a considerable effort, and so
I have not done that in a long time. The code is slowly rotting, and
with new emerging backends it starts to be a burden, since it cannot use
udev, but needs evdev.
Therefore to ease Weston going forward, remove the Android backend. If
someone misses it, it can still be found in the stable 1.0 branch, and
of course resurrected from git history if someone wants to put in the
effort and maintain it.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
We were pulling in cairo and the image loading libraries through libshared.
Split out libshared into a core libshared and a libshared-cairo that
pulls in the extra libraries.
Add a new backend for the Raspberry Pi.
This backend uses the DispmanX API to initialise the display, and create
an EGLSurface, so that GLESv2 rendering is shown on the "framebuffer".
No X server is involved. All compositing happens through GLESv2.
The created EGLSurface is specifically configured as buffer content
preserving, otherwise Weston wouuld show only the latest damage and
everything else was black. This may be sub-optimal, since we are not
alternating between two buffers, like the DRM backend is, and content
preserving may imply a fullscreen copy on each frame.
Page flips are not properly hooked up yet. The display update will
block, and we use a timer to call weston_output_finish_frame(), just
like the x11 backend does.
This backend handles the VT and tty just like the DRM backend does.
While VT switching works in theory, the display output seems to be
frozen while switched away from Weston. You can still switch back.
Seats and connectors cannot be explicitly specified, and multiple seats
are not expected.
Udev is used to find the input devices. Input devices are opened
directly, weston-launch is not supported at this time. You may need to
confirm that your pi user has access to input device nodes.
The Raspberry Pi backend is built by default. It can be build-tested
without the Raspberry Pi headers and libraries, because we provide stubs
in rpi-bcm-stubs.h, but such resulting binary is non-functional. If
using stubs, the backend is built but not installed.
VT and tty handling, and udev related code are pretty much copied from
the DRM backend, hence the copyrights. The rpi-bcm-stubs.h code is
copied from the headers on Raspberry Pi, including their copyright
notice, and modified.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
Instead of hardcoding drm-backend.so as the default if environment
presents neither Wayland nor X11, have a ./configure option to change
it. It still defaults to drm-backend.so, if not given.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
Add a headless backend and a noop renderer, mainly for testing
purposes. Although no rendering is performed with this backend,
this allow some of the code paths inside Weston and shm clients
to be tested without any windowing system or any need for drm
access.
If clients don't set a cursor, they get whatever the last cursor was
before the pointer entered their window. That's a little confusing, so
set a pointer on enter to avoid that. The down-side is that simple EGL
isn't very simple anymore.
https://bugs.freedesktop.org/show_bug.cgi?id=52452
Do not build the tablet-shell client if --disable-tablet-shell is given.
Change --enable-tablet-shell to --disable-tablet-shell in ./configure
--help output, since it is enabled by default. Add a description.
Use proper quoting in the conditional.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
Separate simple EGL clients from other simple clients. This allows to
build either simple-shm or simple-egl, whichever you want. We avoid
linking libEGL and GLESv2 into simple-shm, and we can build simple-shm
even if nothing provides EGL, GLESv2, or wayland-egl APIs.
Change the options in configure --help from --enable to --disable, since
these are enabled by default, and you would normally only ever give the
--disable flavor. Add descriptions.
Remove the #define BUILD_SIMPLE_CLIENTS since it is not used.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
configure.ac: The toytoolkit clients used to get libEGL linked to them
even if there was no cairo-egl. This is useless, and actually harmful on
platforms, where libEGL absolutely requires one of the GL ES libraries
to be linked in, too.
Look for EGL-related packages only for cairo-egl with toytoolkit.
window.c: protect all GL header includes with HAVE_CAIRO_EGL, since that
is the only case we can support EGL, GL, or GLESv2 at all. In the case
we do not have cairo-egl, add enough definitions to let us build the
stubs for EGL-related functions.
Remove some #ifdefs that were inside of the same #ifdef already.
These changes allow to build sorfware rendering toytoolkit clients
without any bits of EGL libs or headers.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
Otherwise the user has no indication which package is missing for
CAIRO_EGL, and has to dig into config.log for it.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
Modify the pkg-config check for setbacklight so that failure only
disables building setbacklight, instead of failing the whole configure.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
This backend has not seen even build testing for months, presumably does
not even compile, and is starting to hinder development a little.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
Cc: Benjamin Franzke <benjaminfranzke@googlemail.com>
This fix xwayland.so that was complaining about jpeg symbols from the
libshared.
Note that xwayland is not using the jpeg ones, but now that symbols are read
up front we need to link anyway.. or break apart that library.
Signed-off-by: Tiago Vignatti <tiago.vignatti@intel.com>
We don't support this anymore. weston requires a setuid helper (such as
weston-launch) to run under kms, and should never run as root itself.
Disabe the setuid warning in configure.ac since we now only install the
minimal weston-launch as setuid.
We had duplicated code in many places, using hardcoded paths for
temporary files into more than one path. Some cases did not bother with
O_CLOEXEC, and all hardcoded paths that might not exist.
Add an OS helper function for creating a unique anonymous file with
close-on-exec semantics. The helper uses $XDG_RUNTIME_DIR as the
directory for a file.
This patch unifies the buffer file creation in both Weston and the
clients.
As simple clients are better not linking to libshared, as it would
require e.g. Cairo, they pull the OS compatibility code directly.
Android does not have mkostemp(), so a configure test is added for it,
and a fallback used if it is not available.
Changes in v2:
remove all the alternate possible directory definitions and use
XDG_RUNTIME_DIR only, and fail is it is not set.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
The patch "compositor-android: fix build flags" started using GCC_CFLAGS
for C++ files, too. That lead to the following warnings when building a
C++ file:
cc1plus: warning: command line option "-Wstrict-prototypes" is valid for
Ada/C/ObjC but not for C++
cc1plus: warning: command line option "-Wmissing-prototypes" is valid
for Ada/C/ObjC but not for C++
Introduce GCC_CXXFLAGS, similar to GCC_CFLAGS, but for C++, avoiding the
problematic compiler flags.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
The Android backend provides basic EGL/GLES2 graphics, where everything
is always composited. Overlays are not used. Input is stubbed, therefore
there is no input yet.
This adds the first C++ source file into Weston compositor. The Android
gralloc and fb HAL glue code to the Android EGL library is in C++, and
there is no way to access it from plain C. We have a simple wrapper to
the required C++ class API. Android forces the C++ file name extension
to .cpp.
The android backend is compiled by default. However, all Android
specific calls are protected with #ifdef ANDROID, so it will build also
without Android headers. The binary produced without the Android build
system is useless, but allows build-testing generic Weston changes.
Therefore the android backend is not installed.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
Some systems may not have execinfo.h. Add a configure test for it, and
if it is not found, make the backtrace() call a no-operation.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
There are no dependencies or requirements there that we don't already
need for weston itself. So lets just always build them.
Use check_PROGRAMS for the matrix unit test case.
weston-launch starts weston and provides mechanism
for weston to set/drop drm master, open a tty,
and read input devices without being root.
Execution is allowed for local-active sessions
or users in the group weston-launch.
mtdev library translates all multitouch based devices to the slotted evdev
protocol. It provides an uniform interface for Weston, which eases mt
implementation when dealing with a big variety of devices.
Weston on drm now directly depends on such library.
Signed-off-by: Tiago Vignatti <tiago.vignatti@intel.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
libbacklight is 300 lines of code in one .c file, and we're relying on
udev changes that aren't yet upstream. For now, let's just keep a
copy in weston and if the Xorg DDX drivers start using libbacklight and
it becomes more widely available, we'll make it an external dependency.
DPMS kicks in only when wscreensaver is launched, in the moment that shell
call lock() for the second time. Backlight control internals are managed by
libbacklight:
http://cgit.freedesktop.org/~vignatti/libbacklight/
Signed-off-by: Tiago Vignatti <tiago.vignatti@intel.com>
http://lists.freedesktop.org/archives/wayland-devel/2012-January/001975.html
reports a linking problem:
/usr/bin/ld: libtoytoolkit.a(cairo-util.o): undefined reference to
symbol 'png_set_filler@@PNG12_0'
/usr/bin/ld: note: 'png_set_filler@@PNG12_0' is defined in DSO
/usr/lib/i386-linux-gnu/libpng12.so.0 so try adding it to the linker command line
/usr/lib/i386-linux-gnu/libpng12.so.0: could not read symbols: Invalid
operation
collect2: ld returned 1 exit status
make[3]: [weston-terminal] Error 1 (ignored)
A similar problem is diagnosed here:
http://lists.fedoraproject.org/pipermail/devel/2010-March/133601.html
As some distros are shipping linkers, that do not resolve symbols from
implicitly linked libraries, check and link libpng explicitly.
Cc: nerdopolis <bluescreen_avenger@verizon.net>
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
Do not build toytoolkit applications that use GL, if Cairo-egl is not
available. These applications (which happen to be also the full GL
clients) do not work at all without Cairo-egl, and fail at runtime with
"unable to acquire window surface".
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
Add a new directory tests/ for unit test applications. This directory
will be built only if --enable-tests is given to ./configure.
Add matrix-test application. It excercises especially the
weston_matrix_invert() and weston_matrix_inverse_transform() functions.
It has one test for correctness and precision, and other tests for
measuring the speed of various matrix operations.
For the record, the correctness test prints:
a random matrix:
1.112418e-02 2.628150e+00 8.205844e+02 -1.147526e-04
4.943677e-04 -1.117819e-04 -9.158849e-06 3.678122e-02
7.915063e-03 -3.093254e-04 -4.376583e+02 3.424706e-02
-2.504038e+02 2.481788e+03 -7.545445e+01 1.752909e-03
The matrix multiplied by its inverse, error:
0.000000e+00 -0.000000e+00 -0.000000e+00 -0.000000e+00
0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00
-0.000000e+00 -0.000000e+00 0.000000e+00 -0.000000e+00
0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00
max abs error: 0, original determinant 11595.2
Running a test loop for 10 seconds...
test fail, det: -0.00464805, error sup: inf
test fail, det: -0.0424053, error sup: 1.30787e-06
test fail, det: 5.15191, error sup: 1.15956e-06
tests: 6791767 ok, 1 not invertible but ok, 3 failed.
Total: 6791771 iterations.
These results are expected with the current precision thresholds in
src/matrix.c and tests/matrix-test.c. The random number generator is
seeded with a constant, so the random numbers should be the same on
every run. Machine speed and scheduling affect how many iterations are
run.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
This rename addresses a few problems around the split between core
Wayland and the wayland-demos repository.
1) Initially, we had one big repository with protocol code, sample
compositor and sample clients. We split that repository to make it
possible to implement the protocol without pulling in the sample/demo
code. At this point, the compositor is more than just a "demo" and
wayland-demos doesn't send the right message. The sample compositor
is a useful, self-contained project in it's own right, and we want to
move away from the "demos" label.
2) Another problem is that the wayland-demos compositor is often
called "the wayland compsitor", but it's really just one possible
compositor. Existing X11 compositors are expected to add Wayland
support and then gradually phase out/modularize the X11 support, for
example. Conversely, it's hard to talk about the wayland-demos
compositor specifically as opposed to, eg, the wayland protocol or a
wayland compositor in general.
We are also renaming the repo to weston, and the compositor
subdirectory to src/, to emphasize that the main "output" is the
compositor.
Create a new directory for convenience librariers that can be shared
between compositor components and clients.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
With this the X server directory can become independent from the
installation prefix set by autoconf.
Signed-off-by: Tiago Vignatti <tiago.vignatti@intel.com>
The shell module is responsible for implementing the higher level
compositor behavior. We default to the desktop-lite shell built in to
the compositor.
For now, we just use glScissor and clip to the extent of the damage region,
but we can do even better by clipping the repaint to the region rectangles.
This shouldn't fail just because someone sets CC=gcc-4.5
explicitly. Besides, this way it also works with compilers
that advertise GCC-compatibility like clang and ICC.
