Previously picking was done on an int (x,y) to address a particular pixel.
While `int` was the minimum precision required, it was also an unnecessary
type conversion.
The callers (input events mainly) all provide float coordinates and the
internal picking calculations also have always used floats. So it was
inconsistent and unnecessary to drop to integer precision in between those.
ABI break: This changes the parameter types for public function
`clutter_stage_get_actor_at_pos`, but its documentation is already
sufficiently vague to not need changing.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/844
Currently, Clutter does picking by drawing with Cogl and reading
the pixel that's beneath the given point. Since Cogl has a journal
that records drawing operations, and has optimizations to read a
single pixel from a list of rectangle, it would be expected that
we would hit this fast path and not flush the journal while picking.
However, that's not the case: dithering, clipping with scissors, etc,
can all flush the journal, issuing commands to the GPU and making
picking slow. On NVidia-based systems, this glReadPixels() call is
extremely costly.
Introduce geometric picking, and avoid using the Cogl journal entirely.
Do this by introducing a stack of actors in ClutterStage. This stack
is cached, but for now, don't use the cache as much as possible.
The picking routines are still tied to painting.
When projecting the actor vertexes, do it manually and take the modelview
matrix of the framebuffer into account as well.
CPU usage on an Intel i7-7700, tested with two different GPUs/drivers:
| | Intel | Nvidia |
| ------: | --------: | -----: |
| Moving the mouse: |
| Before | 10% | 10% |
| After | 6% | 6% |
| Moving a window: |
| Before | 23% | 81% |
| After | 19% | 40% |
Closes: https://gitlab.gnome.org/GNOME/mutter/issues/154,
https://gitlab.gnome.org/GNOME/mutter/issues/691
Helps significantly with: https://gitlab.gnome.org/GNOME/mutter/issues/283,
https://gitlab.gnome.org/GNOME/mutter/issues/590,
https://gitlab.gnome.org/GNOME/mutter/issues/700
v2: Fix code style issues
Simplify quadrilateral checks
Remove the 0.5f hack
Differentiate axis-aligned rectangles
https://gitlab.gnome.org/GNOME/mutter/merge_requests/189
The end goal is to have all clutter backend code in src/backends. Input
is the larger chunk of it, which is now part of our specific
MutterClutterBackendX11, this extends to device manager, input devices,
tools and keymap.
This was supposed to be nice and incremental, but there's no sane way
to cut this through. As a result of the refactor, a number of private
Clutter functions are now exported for external backends to be possible.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/672
ClutterStage:after-paint is supposed to be emitted after all
painting is done, but before the frame is finished. However,
as it is right now, it is being emitted after each view is
painted -- on multi-monitor setups, after-frame is being
emitted multiple times.
Send after-paint only once, after all views are painted and
before finishing the frame.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/623
A clutter actor might be painted on a stage view with a view scale
other than 1. In this case, to show the content in full resolution, the
actor must use a higher resolution resource (e.g. texture), which will
be down scaled to the stage coordinate space, then scaled up again to
the stage view framebuffer scale.
Use a 'resource-scale' property to save information and notify when it
changes.
The resource scale is the ceiled value of the highest stage view scale a
actor is visible on. The value is ceiled because using a higher
resolution resource consistently results in better output quality. One
reason for this is that rendering is often not perfectly pixel aligned,
meaning even if we load a resource with a suitable size, due to us still
scaling ever so slightly, the quality is affected. Using a higher
resolution resource avoids this problem.
For situations inside clutter where the actual maximum view scale is
needed, a function _clutter_actor_get_real_resource_scale() is provided,
which returns the non-ceiled value.
Make sure we ignore resource scale computation requests during size
requests or allocation while ensure we've proper resource-scale on
pre-paint.
https://bugzilla.gnome.org/show_bug.cgi?id=765011https://gitlab.gnome.org/GNOME/mutter/merge_requests/3
CoglFrameInfo is a frame info container associated with a single
onscreen framebuffer. The clutter stage will eventually support drawing
a stage frame with multiple onscreen framebuffers, thus needs its own
frame info container.
This patch introduces a new stage signal 'presented' and a accompaning
ClutterFrameInfo and adapts the stage windows and past onscreen frame
callbacks users to use the signal and new info container.
https://bugzilla.gnome.org/show_bug.cgi?id=768976
Add support for drawing a stage using multiple framebuffers each making
up one part of the stage. This works by the stage backend
(ClutterStageWindow) providing a list of views which will be for
splitting up the stage in different regions.
A view layout, for now, is a set of rectangles. The stage window (i.e.
stage "backend" will use this information when drawing a frame, using
one framebuffer for each view. The scene graph is adapted to explictly
take a view when painting the stage. It will use this view, its
assigned framebuffer and layout to offset and clip the drawing
accordingly.
This effectively removes any notion of "stage framebuffer", since each
stage now may consist of multiple framebuffers. Therefore, API
involving this has been deprecated and made no-ops; namely
clutter_stage_ensure_context(). Callers are now assumed to either
always use a framebuffer reference explicitly, or push/pop the
framebuffer of a given view where the code has not yet changed to use
the explicit-buffer-using cogl API.
Currently only the nested X11 backend supports this mode fully, and the
per view framebuffers are all offscreen. Upon frame completion, it'll
blit each view's framebuffer onto the onscreen framebuffer before
swapping.
Other backends (X11 CM and native/KMS) are adapted to manage a
full-stage view. The X11 CM backend will continue to use this method,
while the native/KMS backend will be adopted to use multiple view
drawing.
https://bugzilla.gnome.org/show_bug.cgi?id=768976
