Add WCT#setDragResizing to optimize fluid resizing

Allows WM Shell to indicate the start/end of drag resizing, which
core can use as a signal to reuse a single (larger) surface size
for the entire drag resize operation to avoid continuous buffer
allocations after each size change.

Bug: 249808500
Test: drag resize a freeform window, verify WindowLayout requests
a fullscreen sized surface; atest TaskPositionerTest

Change-Id: I27e2b44270d7ea4f701fa8037f93b20dc691284b

5 files changed, 198 insertions, 6 deletions

diff --git a/core/java/android/window/WindowContainerTransaction.java b/core/java/android/window/WindowContainerTransaction.java
index cfad1afe1b5b..fbf8d8bf9fe4 100644
--- a/core/java/android/window/WindowContainerTransaction.java
+++ b/core/java/android/window/WindowContainerTransaction.java
@@ -467,6 +467,23 @@ public final class WindowContainerTransaction implements Parcelable {
     }
 
     /**
+     * Sets whether a container is being drag-resized.
+     * When {@code true}, the client will reuse a single (larger) surface size to avoid
+     * continuous allocations on every size change.
+     *
+     * @param container WindowContainerToken of the task that changed its drag resizing state
+     * @hide
+     */
+    @NonNull
+    public WindowContainerTransaction setDragResizing(@NonNull WindowContainerToken container,
+            boolean dragResizing) {
+        final Change change = getOrCreateChange(container.asBinder());
+        change.mChangeMask |= Change.CHANGE_DRAG_RESIZING;
+        change.mDragResizing = dragResizing;
+        return this;
+    }
+
+    /**
      * Sends a pending intent in sync.
      * @param sender The PendingIntent sender.
      * @param intent The fillIn intent to patch over the sender's base intent.
@@ -906,12 +923,14 @@ public final class WindowContainerTransaction implements Parcelable {
         public static final int CHANGE_IGNORE_ORIENTATION_REQUEST = 1 << 5;
         public static final int CHANGE_FORCE_NO_PIP = 1 << 6;
         public static final int CHANGE_FORCE_TRANSLUCENT = 1 << 7;
+        public static final int CHANGE_DRAG_RESIZING = 1 << 8;
 
         private final Configuration mConfiguration = new Configuration();
         private boolean mFocusable = true;
         private boolean mHidden = false;
         private boolean mIgnoreOrientationRequest = false;
         private boolean mForceTranslucent = false;
+        private boolean mDragResizing = false;
 
         private int mChangeMask = 0;
         private @ActivityInfo.Config int mConfigSetMask = 0;
@@ -932,6 +951,7 @@ public final class WindowContainerTransaction implements Parcelable {
             mHidden = in.readBoolean();
             mIgnoreOrientationRequest = in.readBoolean();
             mForceTranslucent = in.readBoolean();
+            mDragResizing = in.readBoolean();
             mChangeMask = in.readInt();
             mConfigSetMask = in.readInt();
             mWindowSetMask = in.readInt();
@@ -980,6 +1000,9 @@ public final class WindowContainerTransaction implements Parcelable {
             if ((other.mChangeMask & CHANGE_FORCE_TRANSLUCENT) != 0) {
                 mForceTranslucent = other.mForceTranslucent;
             }
+            if ((other.mChangeMask & CHANGE_DRAG_RESIZING) != 0) {
+                mDragResizing = other.mDragResizing;
+            }
             mChangeMask |= other.mChangeMask;
             if (other.mActivityWindowingMode >= 0) {
                 mActivityWindowingMode = other.mActivityWindowingMode;
@@ -1039,6 +1062,15 @@ public final class WindowContainerTransaction implements Parcelable {
             return mForceTranslucent;
         }
 
+        /** Gets the requested drag resizing state. */
+        public boolean getDragResizing() {
+            if ((mChangeMask & CHANGE_DRAG_RESIZING) == 0) {
+                throw new RuntimeException("Drag resizing not set. "
+                        + "Check CHANGE_DRAG_RESIZING first");
+            }
+            return mDragResizing;
+        }
+
         public int getChangeMask() {
             return mChangeMask;
         }
@@ -1100,6 +1132,9 @@ public final class WindowContainerTransaction implements Parcelable {
             if ((mChangeMask & CHANGE_FOCUSABLE) != 0) {
                 sb.append("focusable:" + mFocusable + ",");
             }
+            if ((mChangeMask & CHANGE_DRAG_RESIZING) != 0) {
+                sb.append("dragResizing:" + mDragResizing + ",");
+            }
             if (mBoundsChangeTransaction != null) {
                 sb.append("hasBoundsTransaction,");
             }
@@ -1117,6 +1152,7 @@ public final class WindowContainerTransaction implements Parcelable {
             dest.writeBoolean(mHidden);
             dest.writeBoolean(mIgnoreOrientationRequest);
             dest.writeBoolean(mForceTranslucent);
+            dest.writeBoolean(mDragResizing);
             dest.writeInt(mChangeMask);
             dest.writeInt(mConfigSetMask);
             dest.writeInt(mWindowSetMask);
diff --git a/core/java/com/android/internal/policy/DecorView.java b/core/java/com/android/internal/policy/DecorView.java
index a352063aa6ee..f998a690f5a0 100644
--- a/core/java/com/android/internal/policy/DecorView.java
+++ b/core/java/com/android/internal/policy/DecorView.java
@@ -2402,7 +2402,7 @@ public class DecorView extends FrameLayout implements RootViewSurfaceTaker, Wind
             return;
         }
         final ThreadedRenderer renderer = getThreadedRenderer();
-        if (renderer != null) {
+        if (renderer != null && !CAPTION_ON_SHELL) {
             loadBackgroundDrawablesIfNeeded();
             WindowInsets rootInsets = getRootWindowInsets();
             mBackdropFrameRenderer = new BackdropFrameRenderer(this, renderer,
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/TaskPositioner.java b/libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/TaskPositioner.java
index f0f2db7ded80..a49a300995e6 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/TaskPositioner.java
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/TaskPositioner.java
@@ -40,6 +40,9 @@ class TaskPositioner implements DragResizeCallback {
     private final Rect mTaskBoundsAtDragStart = new Rect();
     private final PointF mResizeStartPoint = new PointF();
     private final Rect mResizeTaskBounds = new Rect();
+    // Whether the |dragResizing| hint should be sent with the next bounds change WCT.
+    // Used to optimized fluid resizing of freeform tasks.
+    private boolean mPendingDragResizeHint = false;
 
     private int mCtrlType;
     private DragStartListener mDragStartListener;
@@ -53,6 +56,12 @@ class TaskPositioner implements DragResizeCallback {
 
     @Override
     public void onDragResizeStart(int ctrlType, float x, float y) {
+        if (ctrlType != CTRL_TYPE_UNDEFINED) {
+            // The task is being resized, send the |dragResizing| hint to core with the first
+            // bounds-change wct.
+            mPendingDragResizeHint = true;
+        }
+
         mDragStartListener.onDragStart(mWindowDecoration.mTaskInfo.taskId);
         mCtrlType = ctrlType;
 
@@ -63,19 +72,31 @@ class TaskPositioner implements DragResizeCallback {
 
     @Override
     public void onDragResizeMove(float x, float y) {
-        changeBounds(x, y);
+        final WindowContainerTransaction wct = new WindowContainerTransaction();
+        if (changeBounds(wct, x, y)) {
+            if (mPendingDragResizeHint) {
+                // This is the first bounds change since drag resize operation started.
+                wct.setDragResizing(mWindowDecoration.mTaskInfo.token, true /* dragResizing */);
+                mPendingDragResizeHint = false;
+            }
+            mTaskOrganizer.applyTransaction(wct);
+        }
     }
 
     @Override
     public void onDragResizeEnd(float x, float y) {
-        changeBounds(x, y);
+        final WindowContainerTransaction wct = new WindowContainerTransaction();
+        wct.setDragResizing(mWindowDecoration.mTaskInfo.token, false /* dragResizing */);
+        changeBounds(wct, x, y);
+        mTaskOrganizer.applyTransaction(wct);
 
         mCtrlType = 0;
         mTaskBoundsAtDragStart.setEmpty();
         mResizeStartPoint.set(0, 0);
+        mPendingDragResizeHint = false;
     }
 
-    private void changeBounds(float x, float y) {
+    private boolean changeBounds(WindowContainerTransaction wct, float x, float y) {
         float deltaX = x - mResizeStartPoint.x;
         mResizeTaskBounds.set(mTaskBoundsAtDragStart);
         if ((mCtrlType & CTRL_TYPE_LEFT) != 0) {
@@ -96,10 +117,10 @@ class TaskPositioner implements DragResizeCallback {
         }
 
         if (!mResizeTaskBounds.isEmpty()) {
-            final WindowContainerTransaction wct = new WindowContainerTransaction();
             wct.setBounds(mWindowDecoration.mTaskInfo.token, mResizeTaskBounds);
-            mTaskOrganizer.applyTransaction(wct);
+            return true;
         }
+        return false;
     }
 
     interface DragStartListener {
diff --git a/libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/windowdecor/TaskPositionerTest.kt b/libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/windowdecor/TaskPositionerTest.kt
new file mode 100644
index 000000000000..ac10ddb0116a
--- /dev/null
+++ b/libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/windowdecor/TaskPositionerTest.kt
@@ -0,0 +1,130 @@
+package com.android.wm.shell.windowdecor
+
+import android.app.ActivityManager
+import android.graphics.Rect
+import android.os.IBinder
+import android.testing.AndroidTestingRunner
+import android.window.WindowContainerToken
+import android.window.WindowContainerTransaction.Change.CHANGE_DRAG_RESIZING
+import androidx.test.filters.SmallTest
+import com.android.wm.shell.ShellTaskOrganizer
+import com.android.wm.shell.ShellTestCase
+import com.android.wm.shell.windowdecor.TaskPositioner.CTRL_TYPE_RIGHT
+import com.android.wm.shell.windowdecor.TaskPositioner.CTRL_TYPE_UNDEFINED
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mockito.Mock
+import org.mockito.Mockito.argThat
+import org.mockito.Mockito.never
+import org.mockito.Mockito.verify
+import org.mockito.Mockito.`when`
+import org.mockito.MockitoAnnotations
+
+/**
+ * Tests for [TaskPositioner].
+ *
+ * Build/Install/Run:
+ * atest WMShellUnitTests:TaskPositionerTest
+ */
+@SmallTest
+@RunWith(AndroidTestingRunner::class)
+class TaskPositionerTest : ShellTestCase() {
+
+    @Mock
+    private lateinit var mockShellTaskOrganizer: ShellTaskOrganizer
+    @Mock
+    private lateinit var mockWindowDecoration: WindowDecoration<*>
+    @Mock
+    private lateinit var mockDragStartListener: TaskPositioner.DragStartListener
+
+    @Mock
+    private lateinit var taskToken: WindowContainerToken
+    @Mock
+    private lateinit var taskBinder: IBinder
+
+    private lateinit var taskPositioner: TaskPositioner
+
+    @Before
+    fun setUp() {
+        MockitoAnnotations.initMocks(this)
+
+        taskPositioner = TaskPositioner(
+                mockShellTaskOrganizer,
+                mockWindowDecoration,
+                mockDragStartListener
+        )
+        `when`(taskToken.asBinder()).thenReturn(taskBinder)
+        mockWindowDecoration.mTaskInfo = ActivityManager.RunningTaskInfo().apply {
+            taskId = TASK_ID
+            token = taskToken
+            configuration.windowConfiguration.bounds = STARTING_BOUNDS
+        }
+    }
+
+    @Test
+    fun testDragResize_move_skipsDragResizingFlag() {
+        taskPositioner.onDragResizeStart(
+                CTRL_TYPE_UNDEFINED, // Move
+                STARTING_BOUNDS.left.toFloat(),
+                STARTING_BOUNDS.top.toFloat()
+        )
+
+        // Move the task 10px to the right.
+        val newX = STARTING_BOUNDS.left.toFloat() + 10
+        val newY = STARTING_BOUNDS.top.toFloat()
+        taskPositioner.onDragResizeMove(
+                newX,
+                newY
+        )
+
+        taskPositioner.onDragResizeEnd(newX, newY)
+
+        verify(mockShellTaskOrganizer, never()).applyTransaction(argThat { wct ->
+            return@argThat wct.changes.any { (token, change) ->
+                token == taskBinder &&
+                        ((change.changeMask and CHANGE_DRAG_RESIZING) != 0) &&
+                        change.dragResizing
+            }
+        })
+    }
+
+    @Test
+    fun testDragResize_resize_setsDragResizingFlag() {
+        taskPositioner.onDragResizeStart(
+                CTRL_TYPE_RIGHT, // Resize right
+                STARTING_BOUNDS.left.toFloat(),
+                STARTING_BOUNDS.top.toFloat()
+        )
+
+        // Resize the task by 10px to the right.
+        val newX = STARTING_BOUNDS.right.toFloat() + 10
+        val newY = STARTING_BOUNDS.top.toFloat()
+        taskPositioner.onDragResizeMove(
+                newX,
+                newY
+        )
+
+        taskPositioner.onDragResizeEnd(newX, newY)
+
+        verify(mockShellTaskOrganizer).applyTransaction(argThat { wct ->
+            return@argThat wct.changes.any { (token, change) ->
+                token == taskBinder &&
+                        ((change.changeMask and CHANGE_DRAG_RESIZING) != 0) &&
+                        change.dragResizing
+            }
+        })
+        verify(mockShellTaskOrganizer).applyTransaction(argThat { wct ->
+            return@argThat wct.changes.any { (token, change) ->
+                token == taskBinder &&
+                        ((change.changeMask and CHANGE_DRAG_RESIZING) != 0) &&
+                        !change.dragResizing
+            }
+        })
+    }
+
+    companion object {
+        private const val TASK_ID = 5
+        private val STARTING_BOUNDS = Rect(0, 0, 100, 100)
+    }
+}
diff --git a/services/core/java/com/android/server/wm/WindowOrganizerController.java b/services/core/java/com/android/server/wm/WindowOrganizerController.java
index 32a110ea530e..53daf204fa89 100644
--- a/services/core/java/com/android/server/wm/WindowOrganizerController.java
+++ b/services/core/java/com/android/server/wm/WindowOrganizerController.java
@@ -48,6 +48,7 @@ import static com.android.internal.protolog.ProtoLogGroup.WM_DEBUG_WINDOW_ORGANI
 import static com.android.server.wm.ActivityTaskManagerService.LAYOUT_REASON_CONFIG_CHANGED;
 import static com.android.server.wm.ActivityTaskManagerService.enforceTaskPermission;
 import static com.android.server.wm.ActivityTaskSupervisor.PRESERVE_WINDOWS;
+import static com.android.server.wm.DragResizeMode.DRAG_RESIZE_MODE_FREEFORM;
 import static com.android.server.wm.Task.FLAG_FORCE_HIDDEN_FOR_PINNED_TASK;
 import static com.android.server.wm.Task.FLAG_FORCE_HIDDEN_FOR_TASK_ORG;
 import static com.android.server.wm.TaskFragment.EMBEDDING_ALLOWED;
@@ -725,6 +726,10 @@ class WindowOrganizerController extends IWindowOrganizerController.Stub
             effects = TRANSACT_EFFECTS_LIFECYCLE;
         }
 
+        if ((c.getChangeMask() & WindowContainerTransaction.Change.CHANGE_DRAG_RESIZING) != 0) {
+            tr.setDragResizing(c.getDragResizing(), DRAG_RESIZE_MODE_FREEFORM);
+        }
+
         final int childWindowingMode = c.getActivityWindowingMode();
         if (childWindowingMode > -1) {
             tr.setActivityWindowingMode(childWindowingMode);