Merge "Customize auto-brightness parameters"
am: a3931897fd

* commit 'a3931897fd4f8196288e37c712ab5490d846cb38':
  Customize auto-brightness parameters
diff --git a/core/res/res/values/config.xml b/core/res/res/values/config.xml
index c1a2038..7aeba81 100644
--- a/core/res/res/values/config.xml
+++ b/core/res/res/values/config.xml
@@ -1002,6 +1002,10 @@
     <!-- Light sensor event rate in milliseconds for automatic brightness control. -->
     <integer name="config_autoBrightnessLightSensorRate">250</integer>
 
+    <!-- The maximum range of gamma adjustment possible using the screen
+         auto-brightness adjustment setting. -->
+    <fraction name="config_autoBrightnessAdjustmentMaxGamma">300%</fraction>
+
     <!-- If we allow automatic adjustment of screen brightness while dozing, how many times we want
          to reduce it to preserve the battery. Value of 100% means no scaling. -->
     <fraction name="config_screenAutoBrightnessDozeScaleFactor">100%</fraction>
@@ -1019,6 +1023,9 @@
          adapt to the environment.  This mode may be better suited for watches. -->
     <bool name="config_autoBrightnessResetAmbientLuxAfterWarmUp">true</bool>
 
+    <!-- Period of time in which to consider light samples in milliseconds. -->
+    <integer name="config_autoBrightnessAmbientLightHorizon">10000</integer>
+
     <!-- Screen brightness used to dim the screen when the user activity
          timeout expires.  May be less than the minimum allowed brightness setting
          that can be set by the user. -->
diff --git a/core/res/res/values/symbols.xml b/core/res/res/values/symbols.xml
index 868e4c5..a300b8c 100644
--- a/core/res/res/values/symbols.xml
+++ b/core/res/res/values/symbols.xml
@@ -1688,6 +1688,8 @@
   <java-symbol type="id" name="replace_message" />
   <java-symbol type="fraction" name="config_dimBehindFadeDuration" />
   <java-symbol type="fraction" name="config_screenAutoBrightnessDozeScaleFactor" />
+  <java-symbol type="fraction" name="config_autoBrightnessAdjustmentMaxGamma" />
+  <java-symbol type="integer" name="config_autoBrightnessAmbientLightHorizon"/>
   <java-symbol type="integer" name="config_autoBrightnessBrighteningLightDebounce"/>
   <java-symbol type="integer" name="config_autoBrightnessDarkeningLightDebounce"/>
   <java-symbol type="integer" name="config_autoBrightnessLightSensorRate"/>
diff --git a/services/core/java/com/android/server/display/AutomaticBrightnessController.java b/services/core/java/com/android/server/display/AutomaticBrightnessController.java
index e15bca6..1908f72 100644
--- a/services/core/java/com/android/server/display/AutomaticBrightnessController.java
+++ b/services/core/java/com/android/server/display/AutomaticBrightnessController.java
@@ -49,23 +49,12 @@
     // If true, enables the use of the screen auto-brightness adjustment setting.
     private static final boolean USE_SCREEN_AUTO_BRIGHTNESS_ADJUSTMENT = true;
 
-    // The maximum range of gamma adjustment possible using the screen
-    // auto-brightness adjustment setting.
-    private static final float SCREEN_AUTO_BRIGHTNESS_ADJUSTMENT_MAX_GAMMA = 3.0f;
-
-    // Period of time in which to consider light samples in milliseconds.
-    private static final int AMBIENT_LIGHT_HORIZON = 10000;
-
     // Hysteresis constraints for brightening or darkening.
     // The recent lux must have changed by at least this fraction relative to the
     // current ambient lux before a change will be considered.
     private static final float BRIGHTENING_LIGHT_HYSTERESIS = 0.10f;
     private static final float DARKENING_LIGHT_HYSTERESIS = 0.20f;
 
-    // The intercept used for the weighting calculation. This is used in order to keep all possible
-    // weighting values positive.
-    private static final int WEIGHTING_INTERCEPT = AMBIENT_LIGHT_HORIZON;
-
     // How long the current sensor reading is assumed to be valid beyond the current time.
     // This provides a bit of prediction, as well as ensures that the weight for the last sample is
     // non-zero, which in turn ensures that the total weight is non-zero.
@@ -132,6 +121,13 @@
     // and only then decide whether to change brightness.
     private final boolean mResetAmbientLuxAfterWarmUpConfig;
 
+    // Period of time in which to consider light samples in milliseconds.
+    private final int mAmbientLightHorizon;
+
+    // The intercept used for the weighting calculation. This is used in order to keep all possible
+    // weighting values positive.
+    private final int mWeightingIntercept;
+
     // Amount of time to delay auto-brightness after screen on while waiting for
     // the light sensor to warm-up in milliseconds.
     // May be 0 if no warm-up is required.
@@ -179,6 +175,10 @@
     // The screen auto-brightness adjustment factor in the range -1 (dimmer) to 1 (brighter)
     private float mScreenAutoBrightnessAdjustment = 0.0f;
 
+    // The maximum range of gamma adjustment possible using the screen
+    // auto-brightness adjustment setting.
+    private float mScreenAutoBrightnessAdjustmentMaxGamma;
+
     // The last screen auto-brightness gamma.  (For printing in dump() only.)
     private float mLastScreenAutoBrightnessGamma = 1.0f;
 
@@ -197,7 +197,8 @@
             SensorManager sensorManager, Spline autoBrightnessSpline, int lightSensorWarmUpTime,
             int brightnessMin, int brightnessMax, float dozeScaleFactor,
             int lightSensorRate, long brighteningLightDebounceConfig,
-            long darkeningLightDebounceConfig, boolean resetAmbientLuxAfterWarmUpConfig) {
+            long darkeningLightDebounceConfig, boolean resetAmbientLuxAfterWarmUpConfig,
+            int ambientLightHorizon, float autoBrightnessAdjustmentMaxGamma ) {
         mCallbacks = callbacks;
         mTwilight = LocalServices.getService(TwilightManager.class);
         mSensorManager = sensorManager;
@@ -210,9 +211,12 @@
         mBrighteningLightDebounceConfig = brighteningLightDebounceConfig;
         mDarkeningLightDebounceConfig = darkeningLightDebounceConfig;
         mResetAmbientLuxAfterWarmUpConfig = resetAmbientLuxAfterWarmUpConfig;
+        mAmbientLightHorizon = ambientLightHorizon;
+        mWeightingIntercept = ambientLightHorizon;
+        mScreenAutoBrightnessAdjustmentMaxGamma = autoBrightnessAdjustmentMaxGamma;
 
         mHandler = new AutomaticBrightnessHandler(looper);
-        mAmbientLightRingBuffer = new AmbientLightRingBuffer(mLightSensorRate);
+        mAmbientLightRingBuffer = new AmbientLightRingBuffer(mLightSensorRate, mAmbientLightHorizon);
 
         if (!DEBUG_PRETEND_LIGHT_SENSOR_ABSENT) {
             mLightSensor = mSensorManager.getDefaultSensor(Sensor.TYPE_LIGHT);
@@ -266,6 +270,7 @@
         pw.println("  mLightSensorEnabled=" + mLightSensorEnabled);
         pw.println("  mLightSensorEnableTime=" + TimeUtils.formatUptime(mLightSensorEnableTime));
         pw.println("  mAmbientLux=" + mAmbientLux);
+        pw.println("  mAmbientLightHorizon=" + mAmbientLightHorizon);
         pw.println("  mBrighteningLuxThreshold=" + mBrighteningLuxThreshold);
         pw.println("  mDarkeningLuxThreshold=" + mDarkeningLuxThreshold);
         pw.println("  mLastObservedLux=" + mLastObservedLux);
@@ -274,6 +279,7 @@
         pw.println("  mAmbientLightRingBuffer=" + mAmbientLightRingBuffer);
         pw.println("  mScreenAutoBrightness=" + mScreenAutoBrightness);
         pw.println("  mScreenAutoBrightnessAdjustment=" + mScreenAutoBrightnessAdjustment);
+        pw.println("  mScreenAutoBrightnessAdjustmentMaxGamma=" + mScreenAutoBrightnessAdjustmentMaxGamma);
         pw.println("  mLastScreenAutoBrightnessGamma=" + mLastScreenAutoBrightnessGamma);
         pw.println("  mDozing=" + mDozing);
     }
@@ -309,7 +315,7 @@
 
     private void applyLightSensorMeasurement(long time, float lux) {
         mRecentLightSamples++;
-        mAmbientLightRingBuffer.prune(time - AMBIENT_LIGHT_HORIZON);
+        mAmbientLightRingBuffer.prune(time - mAmbientLightHorizon);
         mAmbientLightRingBuffer.push(time, lux);
 
         // Remember this sample value.
@@ -360,14 +366,14 @@
         return sum / totalWeight;
     }
 
-    private static float calculateWeight(long startDelta, long endDelta) {
+    private float calculateWeight(long startDelta, long endDelta) {
         return weightIntegral(endDelta) - weightIntegral(startDelta);
     }
 
-    // Evaluates the integral of y = x + WEIGHTING_INTERCEPT. This is always positive for the
+    // Evaluates the integral of y = x + mWeightingIntercept. This is always positive for the
     // horizon we're looking at and provides a non-linear weighting for light samples.
-    private static float weightIntegral(long x) {
-        return x * (x * 0.5f + WEIGHTING_INTERCEPT);
+    private float weightIntegral(long x) {
+        return x * (x * 0.5f + mWeightingIntercept);
     }
 
     private long nextAmbientLightBrighteningTransition(long time) {
@@ -396,7 +402,7 @@
 
     private void updateAmbientLux() {
         long time = SystemClock.uptimeMillis();
-        mAmbientLightRingBuffer.prune(time - AMBIENT_LIGHT_HORIZON);
+        mAmbientLightRingBuffer.prune(time - mAmbientLightHorizon);
         updateAmbientLux(time);
     }
 
@@ -470,7 +476,7 @@
 
         if (USE_SCREEN_AUTO_BRIGHTNESS_ADJUSTMENT
                 && mScreenAutoBrightnessAdjustment != 0.0f) {
-            final float adjGamma = MathUtils.pow(SCREEN_AUTO_BRIGHTNESS_ADJUSTMENT_MAX_GAMMA,
+            final float adjGamma = MathUtils.pow(mScreenAutoBrightnessAdjustmentMaxGamma,
                     Math.min(1.0f, Math.max(-1.0f, -mScreenAutoBrightnessAdjustment)));
             gamma *= adjGamma;
             if (DEBUG) {
@@ -653,8 +659,8 @@
         private int mEnd;
         private int mCount;
 
-        public AmbientLightRingBuffer(long lightSensorRate) {
-            mCapacity = (int) Math.ceil(AMBIENT_LIGHT_HORIZON * BUFFER_SLACK / lightSensorRate);
+        public AmbientLightRingBuffer(long lightSensorRate, int ambientLightHorizon) {
+            mCapacity = (int) Math.ceil(ambientLightHorizon * BUFFER_SLACK / lightSensorRate);
             mRingLux = new float[mCapacity];
             mRingTime = new long[mCapacity];
         }
diff --git a/services/core/java/com/android/server/display/DisplayPowerController.java b/services/core/java/com/android/server/display/DisplayPowerController.java
index 7b49530..433d887 100644
--- a/services/core/java/com/android/server/display/DisplayPowerController.java
+++ b/services/core/java/com/android/server/display/DisplayPowerController.java
@@ -311,6 +311,11 @@
                 com.android.internal.R.integer.config_autoBrightnessDarkeningLightDebounce);
         boolean autoBrightnessResetAmbientLuxAfterWarmUp = resources.getBoolean(
                 com.android.internal.R.bool.config_autoBrightnessResetAmbientLuxAfterWarmUp);
+        int ambientLightHorizon = resources.getInteger(
+                com.android.internal.R.integer.config_autoBrightnessAmbientLightHorizon);
+        float autoBrightnessAdjustmentMaxGamma = resources.getFraction(
+                com.android.internal.R.fraction.config_autoBrightnessAdjustmentMaxGamma,
+                1, 1);
 
         if (mUseSoftwareAutoBrightnessConfig) {
             int[] lux = resources.getIntArray(
@@ -348,7 +353,8 @@
                         lightSensorWarmUpTimeConfig, screenBrightnessRangeMinimum,
                         mScreenBrightnessRangeMaximum, dozeScaleFactor, lightSensorRate,
                         brighteningLightDebounce, darkeningLightDebounce,
-                        autoBrightnessResetAmbientLuxAfterWarmUp);
+                        autoBrightnessResetAmbientLuxAfterWarmUp,
+                        ambientLightHorizon, autoBrightnessAdjustmentMaxGamma);
             }
         }