From 8624015554c37c48d8611be2af7141750275e335 Mon Sep 17 00:00:00 2001
From: Will <wleshner@google.com>
Date: Wed, 12 Jan 2022 16:54:35 -0800
Subject: [PATCH] Periodically jitter dream overlay to prevent burn-in.

Test: atest DreamOverlayContainerViewControllerTest
Bug: 213907279
Change-Id: Id43d8697c5ef032b07c6f5854445cb16f6c820b7
---
 packages/SystemUI/res/values/config.xml       |  2 +
 .../DreamOverlayContainerViewController.java  | 36 +++++++++++++-
 .../dreams/dagger/DreamOverlayModule.java     | 20 ++++++++
 ...eamOverlayContainerViewControllerTest.java | 49 ++++++++++++++++++-
 4 files changed, 104 insertions(+), 3 deletions(-)

diff --git a/packages/SystemUI/res/values/config.xml b/packages/SystemUI/res/values/config.xml
index 9c35fea6438d5..65f22b805d4e5 100644
--- a/packages/SystemUI/res/values/config.xml
+++ b/packages/SystemUI/res/values/config.xml
@@ -738,4 +738,6 @@
     <!-- Class for the communal source connector to be used -->
     <string name="config_communalSourceConnector" translatable="false"></string>
 
+    <!-- How often in milliseconds to jitter the dream overlay in order to avoid burn-in. -->
+    <integer name="config_dreamOverlayBurnInProtectionUpdateIntervalMillis">500</integer>
 </resources>
diff --git a/packages/SystemUI/src/com/android/systemui/dreams/DreamOverlayContainerViewController.java b/packages/SystemUI/src/com/android/systemui/dreams/DreamOverlayContainerViewController.java
index 572bb4467c979..5b46079c87cca 100644
--- a/packages/SystemUI/src/com/android/systemui/dreams/DreamOverlayContainerViewController.java
+++ b/packages/SystemUI/src/com/android/systemui/dreams/DreamOverlayContainerViewController.java
@@ -16,8 +16,11 @@
 
 package com.android.systemui.dreams;
 
+import static com.android.systemui.doze.util.BurnInHelperKt.getBurnInOffset;
+
 import android.graphics.Rect;
 import android.graphics.Region;
+import android.os.Handler;
 import android.view.View;
 import android.view.ViewGroup;
 import android.view.ViewTreeObserver;
@@ -26,6 +29,7 @@ import androidx.constraintlayout.widget.ConstraintLayout;
 
 import com.android.internal.annotations.VisibleForTesting;
 import com.android.systemui.R;
+import com.android.systemui.dagger.qualifiers.Main;
 import com.android.systemui.dreams.dagger.DreamOverlayComponent;
 import com.android.systemui.dreams.dagger.DreamOverlayModule;
 import com.android.systemui.util.ViewController;
@@ -47,6 +51,15 @@ public class DreamOverlayContainerViewController extends ViewController<DreamOve
     // the space into which widgets are placed.
     private final ViewGroup mDreamOverlayContentView;
 
+    // The maximum translation offset to apply to the overlay container to avoid screen burn-in.
+    private final int mMaxBurnInOffset;
+
+    // The interval in milliseconds between burn-in protection updates.
+    private final long mBurnInProtectionUpdateInterval;
+
+    // Main thread handler used to schedule periodic tasks (e.g. burn-in protection updates).
+    private final Handler mHandler;
+
     // A hook into the internal inset calculation where we declare the overlays as the only
     // touchable regions.
     private final ViewTreeObserver.OnComputeInternalInsetsListener
@@ -81,13 +94,21 @@ public class DreamOverlayContainerViewController extends ViewController<DreamOve
     public DreamOverlayContainerViewController(
             DreamOverlayContainerView containerView,
             @Named(DreamOverlayModule.DREAM_OVERLAY_CONTENT_VIEW) ViewGroup contentView,
-            DreamOverlayStatusBarViewController statusBarViewController) {
+            DreamOverlayStatusBarViewController statusBarViewController,
+            @Main Handler handler,
+            @Named(DreamOverlayModule.MAX_BURN_IN_OFFSET) int maxBurnInOffset,
+            @Named(DreamOverlayModule.BURN_IN_PROTECTION_UPDATE_INTERVAL) long
+                    burnInProtectionUpdateInterval) {
         super(containerView);
         mDreamOverlayContentView = contentView;
         mStatusBarViewController = statusBarViewController;
         mDreamOverlayNotificationsDragAreaHeight =
                 mView.getResources().getDimensionPixelSize(
                         R.dimen.dream_overlay_notifications_drag_area_height);
+
+        mHandler = handler;
+        mMaxBurnInOffset = maxBurnInOffset;
+        mBurnInProtectionUpdateInterval = burnInProtectionUpdateInterval;
     }
 
     @Override
@@ -99,10 +120,12 @@ public class DreamOverlayContainerViewController extends ViewController<DreamOve
     protected void onViewAttached() {
         mView.getViewTreeObserver()
                 .addOnComputeInternalInsetsListener(mOnComputeInternalInsetsListener);
+        mHandler.postDelayed(this::updateBurnInOffsets, mBurnInProtectionUpdateInterval);
     }
 
     @Override
     protected void onViewDetached() {
+        mHandler.removeCallbacks(this::updateBurnInOffsets);
         mView.getViewTreeObserver()
                 .removeOnComputeInternalInsetsListener(mOnComputeInternalInsetsListener);
     }
@@ -123,4 +146,15 @@ public class DreamOverlayContainerViewController extends ViewController<DreamOve
     int getDreamOverlayNotificationsDragAreaHeight() {
         return mDreamOverlayNotificationsDragAreaHeight;
     }
+
+    private void updateBurnInOffsets() {
+        // These translation values change slowly, and the set translation methods are idempotent,
+        // so no translation occurs when the values don't change.
+        mView.setTranslationX(getBurnInOffset(mMaxBurnInOffset * 2, true)
+                - mMaxBurnInOffset);
+        mView.setTranslationY(getBurnInOffset(mMaxBurnInOffset * 2, false)
+                - mMaxBurnInOffset);
+
+        mHandler.postDelayed(this::updateBurnInOffsets, mBurnInProtectionUpdateInterval);
+    }
 }
diff --git a/packages/SystemUI/src/com/android/systemui/dreams/dagger/DreamOverlayModule.java b/packages/SystemUI/src/com/android/systemui/dreams/dagger/DreamOverlayModule.java
index 5b588a9d9023b..d2912032ed395 100644
--- a/packages/SystemUI/src/com/android/systemui/dreams/dagger/DreamOverlayModule.java
+++ b/packages/SystemUI/src/com/android/systemui/dreams/dagger/DreamOverlayModule.java
@@ -17,6 +17,7 @@
 package com.android.systemui.dreams.dagger;
 
 import android.content.ContentResolver;
+import android.content.res.Resources;
 import android.os.Handler;
 import android.view.LayoutInflater;
 import android.view.ViewGroup;
@@ -45,6 +46,9 @@ public abstract class DreamOverlayModule {
     public static final String DREAM_OVERLAY_BATTERY_CONTROLLER =
             "dream_overlay_battery_controller";
     public static final String DREAM_OVERLAY_CONTENT_VIEW = "dream_overlay_content_view";
+    public static final String MAX_BURN_IN_OFFSET = "max_burn_in_offset";
+    public static final String BURN_IN_PROTECTION_UPDATE_INTERVAL =
+            "burn_in_protection_update_interval";
 
     /** */
     @Provides
@@ -104,4 +108,20 @@ public abstract class DreamOverlayModule {
                 contentResolver,
                 batteryController);
     }
+
+    /** */
+    @Provides
+    @DreamOverlayComponent.DreamOverlayScope
+    @Named(MAX_BURN_IN_OFFSET)
+    static int providesMaxBurnInOffset(@Main Resources resources) {
+        return resources.getDimensionPixelSize(R.dimen.default_burn_in_prevention_offset);
+    }
+
+    /** */
+    @Provides
+    @Named(BURN_IN_PROTECTION_UPDATE_INTERVAL)
+    static long providesBurnInProtectionUpdateInterval(@Main Resources resources) {
+        return resources.getInteger(
+                R.integer.config_dreamOverlayBurnInProtectionUpdateIntervalMillis);
+    }
 }
diff --git a/packages/SystemUI/tests/src/com/android/systemui/dreams/DreamOverlayContainerViewControllerTest.java b/packages/SystemUI/tests/src/com/android/systemui/dreams/DreamOverlayContainerViewControllerTest.java
index cf53ccffcdb07..7c5f57fe0b390 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/dreams/DreamOverlayContainerViewControllerTest.java
+++ b/packages/SystemUI/tests/src/com/android/systemui/dreams/DreamOverlayContainerViewControllerTest.java
@@ -19,10 +19,13 @@ package com.android.systemui.dreams;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
 import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyFloat;
+import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
 import android.content.res.Resources;
+import android.os.Handler;
 import android.testing.AndroidTestingRunner;
 import android.view.View;
 import android.view.ViewGroup;
@@ -45,6 +48,8 @@ import org.mockito.MockitoAnnotations;
 @RunWith(AndroidTestingRunner.class)
 public class DreamOverlayContainerViewControllerTest extends SysuiTestCase {
     private static final int DREAM_OVERLAY_NOTIFICATIONS_DRAG_AREA_HEIGHT = 100;
+    private static final int MAX_BURN_IN_OFFSET = 20;
+    private static final long BURN_IN_PROTECTION_UPDATE_INTERVAL = 10;
 
     @Mock
     Resources mResources;
@@ -61,6 +66,9 @@ public class DreamOverlayContainerViewControllerTest extends SysuiTestCase {
     @Mock
     ViewGroup mDreamOverlayContentView;
 
+    @Mock
+    Handler mHandler;
+
     DreamOverlayContainerViewController mController;
 
     @Before
@@ -74,8 +82,12 @@ public class DreamOverlayContainerViewControllerTest extends SysuiTestCase {
         when(mDreamOverlayContainerView.getViewTreeObserver()).thenReturn(mViewTreeObserver);
 
         mController = new DreamOverlayContainerViewController(
-                mDreamOverlayContainerView, mDreamOverlayContentView,
-                mDreamOverlayStatusBarViewController);
+                mDreamOverlayContainerView,
+                mDreamOverlayContentView,
+                mDreamOverlayStatusBarViewController,
+                mHandler,
+                MAX_BURN_IN_OFFSET,
+                BURN_IN_PROTECTION_UPDATE_INTERVAL);
     }
 
     @Test
@@ -129,4 +141,37 @@ public class DreamOverlayContainerViewControllerTest extends SysuiTestCase {
         computeInsetsListenerCapture.getValue().onComputeInternalInsets(info);
         assertNotNull(info.touchableRegion);
     }
+
+    @Test
+    public void testBurnInProtectionStartsWhenContentViewAttached() {
+        mController.onViewAttached();
+        verify(mHandler).postDelayed(any(Runnable.class), eq(BURN_IN_PROTECTION_UPDATE_INTERVAL));
+    }
+
+    @Test
+    public void testBurnInProtectionStopsWhenContentViewDetached() {
+        mController.onViewDetached();
+        verify(mHandler).removeCallbacks(any(Runnable.class));
+    }
+
+    @Test
+    public void testBurnInProtectionUpdatesPeriodically() {
+        ArgumentCaptor<Runnable> runnableCaptor = ArgumentCaptor.forClass(Runnable.class);
+        mController.onViewAttached();
+        verify(mHandler).postDelayed(
+                runnableCaptor.capture(), eq(BURN_IN_PROTECTION_UPDATE_INTERVAL));
+        runnableCaptor.getValue().run();
+        verify(mDreamOverlayContainerView).setTranslationX(anyFloat());
+        verify(mDreamOverlayContainerView).setTranslationY(anyFloat());
+    }
+
+    @Test
+    public void testBurnInProtectionReschedulesUpdate() {
+        ArgumentCaptor<Runnable> runnableCaptor = ArgumentCaptor.forClass(Runnable.class);
+        mController.onViewAttached();
+        verify(mHandler).postDelayed(
+                runnableCaptor.capture(), eq(BURN_IN_PROTECTION_UPDATE_INTERVAL));
+        runnableCaptor.getValue().run();
+        verify(mHandler).postDelayed(runnableCaptor.getValue(), BURN_IN_PROTECTION_UPDATE_INTERVAL);
+    }
 }