Add config_autoBrightnessAmbientLightHorizon overlay

CYNGNOS-1475

Change-Id: I92bf8cfbb0eebb746622de123d3e065f4e47ed97

2 files changed, 23 insertions, 18 deletions

diff --git a/services/core/java/com/android/server/display/AutomaticBrightnessController.java b/services/core/java/com/android/server/display/AutomaticBrightnessController.java
index 575701a..bac4fd1 100644
--- a/services/core/java/com/android/server/display/AutomaticBrightnessController.java
+++ b/services/core/java/com/android/server/display/AutomaticBrightnessController.java
@@ -55,19 +55,12 @@ class AutomaticBrightnessController {
     // 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.
@@ -198,6 +191,13 @@ class AutomaticBrightnessController {
     // Night mode color temperature adjustments
     private final LiveDisplayController mLiveDisplay;
 
+    // Period of time in which to consider light samples in milliseconds.
+    private int mAmbientLightHorizon;
+
+    // The intercept used for the weighting calculation. This is used in order to keep all possible
+    // weighting values positive.
+    private int mWeightingIntercept;
+
     private final Context mContext;
 
     public AutomaticBrightnessController(Context context, Callbacks callbacks, Looper looper,
@@ -205,7 +205,7 @@ class AutomaticBrightnessController {
             int brightnessMin, int brightnessMax, float dozeScaleFactor,
             int lightSensorRate, long brighteningLightDebounceConfig,
             long darkeningLightDebounceConfig, boolean resetAmbientLuxAfterWarmUpConfig,
-            LiveDisplayController ldc) {
+            int ambientLightHorizon, LiveDisplayController ldc) {
         mContext = context;
         mCallbacks = callbacks;
         mTwilight = LocalServices.getService(TwilightManager.class);
@@ -220,9 +220,11 @@ class AutomaticBrightnessController {
         mDarkeningLightDebounceConfig = darkeningLightDebounceConfig;
         mResetAmbientLuxAfterWarmUpConfig = resetAmbientLuxAfterWarmUpConfig;
         mLiveDisplay = ldc;
+        mAmbientLightHorizon = ambientLightHorizon;
+        mWeightingIntercept = ambientLightHorizon;
 
         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);
@@ -319,7 +321,7 @@ class AutomaticBrightnessController {
 
     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.
@@ -370,14 +372,14 @@ class AutomaticBrightnessController {
         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 + mWeightIntercept. 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) {
@@ -406,7 +408,7 @@ class AutomaticBrightnessController {
 
     private void updateAmbientLux() {
         long time = SystemClock.uptimeMillis();
-        mAmbientLightRingBuffer.prune(time - AMBIENT_LIGHT_HORIZON);
+        mAmbientLightRingBuffer.prune(time - mAmbientLightHorizon);
         updateAmbientLux(time);
     }
 
@@ -666,8 +668,8 @@ class AutomaticBrightnessController {
         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 38c4180..0d795dd 100644
--- a/services/core/java/com/android/server/display/DisplayPowerController.java
+++ b/services/core/java/com/android/server/display/DisplayPowerController.java
@@ -321,6 +321,8 @@ final class DisplayPowerController implements AutomaticBrightnessController.Call
                 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);
 
         if (mUseSoftwareAutoBrightnessConfig) {
             int[] lux = resources.getIntArray(
@@ -358,7 +360,8 @@ final class DisplayPowerController implements AutomaticBrightnessController.Call
                         lightSensorWarmUpTimeConfig, screenBrightnessRangeMinimum,
                         mScreenBrightnessRangeMaximum, dozeScaleFactor, lightSensorRate,
                         brighteningLightDebounce, darkeningLightDebounce,
-                        autoBrightnessResetAmbientLuxAfterWarmUp, mLiveDisplayController);
+                        autoBrightnessResetAmbientLuxAfterWarmUp, ambientLightHorizon,
+                        mLiveDisplayController);
             }
         }