Commit Graph

10 Commits

Author SHA1 Message Date
Jeff Brown
aa202a6dc3 Add a mechanism to adjust auto-brightness at night.
Uses the twilight service to determine the hours of
sunrise and sunset.  Shortly after sunset or before sunrise
gradually start to apply a gamma correction factor to the
auto-brightness calculations to make the screen a little
dimmer at night.

The effect is relatively small and is mostly noticeable
in dark rooms.  This is just a first pass at the algorithm,
we can tweak the adjustment later to ensure that it has even less
impact in moderate or bright environments.

Change-Id: Idf89022a5d0bb52975e04779352d53fa63371178
2012-08-22 00:02:41 -07:00
Jeff Brown
330560f53b Add support for auto-brightness adjust, but leave it disabled.
Auto-brightness adjustment applies a gamma correction factor
between 1/3 and 3 depending on the setting.  This feature
is disabled for now.

Change-Id: I2b300b5c455da545bea56b2bae5bc7903e30f30e
2012-08-21 22:27:42 -07:00
Jeff Brown
5356c7dc72 Disable electron beam on animation.
We want the screen to come back on as soon as possible.

Change-Id: Ifdaa2e88d19590c3da53be985dd886633e5cac59
2012-08-20 20:19:16 -07:00
Jeff Brown
5f47ba4db7 Adjust auto-brightness time constants.
Specifically, dim a little more slowly.

Change-Id: I10d66a83ddc3a63f8c93d740a0cb116e6c974d10
2012-08-20 14:02:12 -07:00
Jeff Brown
6307a150d3 Fix some proximity sensor bugs.
Forgot to clear waiting for proximity negative flag.
Waiting for proximity negative also shouldn't turn the screen off
if it is currently on.

Change-Id: I9885b2f54b185beb961acda44176bc5f11a9f58b
2012-08-20 13:25:08 -07:00
Jeff Brown
98365d7663 Refactor for multi-display support.
Split WindowManagerImpl into two parts, the WindowManager
interface implementation remains where it is but the global
communications with the window manager are now handled by
the WindowManagerGlobal class.  This change greatly simplifies
the challenge of having separate WindowManager instances
for each Context.

Removed WindowManagerImpl.getDefault().  This represents the
bulk of this change.  Most of the usages of this method were
either to perform global functions (now handled by WindowManagerGlobal)
or to obtain the default display (now handled by DisplayManager).

Explicitly associate each new window with a display and make
the Display object available to the View hierarchy.

Add stubs for some new display manager API features.

Start to split apart the concepts of display id and layer stack.
since they operate at different layers of abstraction.
While it's true that each logical display uniquely corresponds to a
surface flinger layer stack, it is not necessarily the case that
they must use the same ids.  Added Display.getLayerStack()
and started using it in places where it was relatively easy to do.

Change-Id: I29ed909114dec86807c4d3a5059c3fa0358bea61
2012-08-19 22:42:08 -07:00
Jeff Brown
13c589b66c Animate brightness with electron beam.
Also added an internal flag to control whether the electron beam
on animation is used.  It's on for now but we might want to
turn if off if we can't get the HAL to provide the
necessary screen on synchronization on all devices.

Change-Id: Iaa3cfa0fd61de10174e68351e4db890eff2d2918
2012-08-16 16:26:54 -07:00
Jeff Brown
1a30b55036 Use spline interpolation for auto-brightness.
Strictly speaking, this is a change in behavior for all products.
Instead of using discrete zones, they will all now use spline
interpolation.  We could make this behavior configurable
but there seems to be little point to it.  The range of brightness
values used will be more or less the same as before, it's just
that what used to be the brightness value for all levels within
a particular zone now becomes the brightness value for the
highest level in that zone and lower values are used for lower
levels within the zone.

Change-Id: I39804ee630ba55f018e1e53c0576b28e7bd27931
2012-08-16 01:45:10 -07:00
Jeff Brown
06565b64de Improve auto-brightness debounce.
Change-Id: I045e2a14cb31ff987a22872733c442fc92ebadbf
2012-08-15 21:10:32 -07:00
Jeff Brown
9630704ed3 Power manager rewrite.
The major goal of this rewrite is to make it easier to implement
power management policies correctly.  According, the new
implementation primarily uses state-based rather than event-based
triggers for applying changes to the current power state.

For example, when an application requests that the proximity
sensor be used to manage the screen state (by way of a wake lock),
the power manager makes note of the fact that the set of
wake locks changed.  Then it executes a common update function
that recalculates the entire state, first looking at wake locks,
then considering user activity, and eventually determining whether
the screen should be turned on or off.  At this point it may
make a request to a component called the DisplayPowerController
to asynchronously update the display's powe state.  Likewise,
DisplayPowerController makes note of the updated power request
and schedules its own update function to figure out what needs
to be changed.

The big benefit of this approach is that it's easy to mutate
multiple properties of the power state simultaneously then
apply their joint effects together all at once.  Transitions
between states are detected and resolved by the update in
a consistent manner.

The new power manager service has is implemented as a set of
loosely coupled components.  For the most part, information
only flows one way through these components (by issuing a
request to that component) although some components support
sending a message back to indicate when the work has been
completed.  For example, the DisplayPowerController posts
a callback runnable asynchronously to tell the PowerManagerService
when the display is ready.  An important feature of this
approach is that each component neatly encapsulates its
state and maintains its own invariants.  Moreover, we do
not need to worry about deadlocks or awkward mutual exclusion
semantics because most of the requests are asynchronous.

The benefits of this design are especially apparent in
the implementation of the screen on / off and brightness
control animations which are able to take advantage of
framework features like properties, ObjectAnimator
and Choreographer.

The screen on / off animation is now the responsibility
of the power manager (instead of surface flinger).  This change
makes it much easier to ensure that the animation is properly
coordinated with other power state changes and eliminates
the cause of race conditions in the older implementation.

The because of the userActivity() function has been changed
so that it never wakes the device from sleep.  This change
removes ambiguity around forcing or disabling user activity
for various purposes.  To wake the device, use wakeUp().
To put it to sleep, use goToSleep().  Simple.

The power manager service interface and API has been significantly
simplified and consolidated.  Also fixed some inconsistencies
related to how the minimum and maximum screen brightness setting
was presented in brightness control widgets and enforced behind
the scenes.

At present the following features are implemented:

- Wake locks.
- User activity.
- Wake up / go to sleep.
- Power state broadcasts.
- Battery stats and event log notifications.
- Dreams.
- Proximity screen off.
- Animated screen on / off transitions.
- Auto-dimming.
- Auto-brightness control for the screen backlight with
  different timeouts for ramping up versus ramping down.
- Auto-on when plugged or unplugged.
- Stay on when plugged.
- Device administration maximum user activity timeout.
- Application controlled brightness via window manager.

The following features are not yet implemented:

- Reduced user activity timeout for the key guard.
- Reduced user activity timeout for the phone application.
- Coordinating screen on barriers with the window manager.
- Preventing auto-rotation during power state changes.
- Auto-brightness adjustment setting (feature was disabled
  in previous version of the power manager service pending
  an improved UI design so leaving it out for now).
- Interpolated brightness control (a proposed new scheme
  for more compactly specifying auto-brightness levels
  in config.xml).
- Button / keyboard backlight control.
- Change window manager to associated WorkSource with
  KEEP_SCREEN_ON_FLAG wake lock instead of talking
  directly to the battery stats service.
- Optionally support animating screen brightness when
  turning on/off instead of playing electron beam animation
  (config_animateScreenLights).

Change-Id: I1d7a52e98f0449f76d70bf421f6a7f245957d1d7
2012-08-15 03:06:24 -07:00