ViewRootImpl: Add USE_BLAST flag.

Add support for ViewRootImpl submitting buffers using
BLAST and put this support behind a disabled-by-default
FLAG.

Bug: 135786080
Change-Id: Ia3f205e34db9f9aa574c9c2e2c499dd3046af220

3 files changed, 78 insertions, 6 deletions

diff --git a/core/java/android/view/SurfaceControl.java b/core/java/android/view/SurfaceControl.java
index b685cf098b33..abc878af7502 100644
--- a/core/java/android/view/SurfaceControl.java
+++ b/core/java/android/view/SurfaceControl.java
@@ -200,7 +200,10 @@ public final class SurfaceControl implements Parcelable {
 
     private final CloseGuard mCloseGuard = CloseGuard.get();
     private String mName;
-    long mNativeObject; // package visibility only for Surface.java access
+    /**
+     * @hide
+     */
+    public long mNativeObject;
 
     // TODO: Move this to native.
     private final Object mSizeLock = new Object();
@@ -319,6 +322,11 @@ public final class SurfaceControl implements Parcelable {
     public static final int FX_SURFACE_CONTAINER = 0x00080000;
 
     /**
+     * @hide
+     */
+    public static final int FX_SURFACE_BLAST = 0x00040000;
+
+    /**
      * Mask used for FX values above.
      *
      * @hide
@@ -694,6 +702,14 @@ public final class SurfaceControl implements Parcelable {
         }
 
         /**
+         * @hide
+         */
+        public Builder setBLASTLayer() {
+            unsetBufferSize();
+            return setFlags(FX_SURFACE_BLAST, FX_SURFACE_MASK);
+        }
+
+        /**
          * Indicates whether a 'ContainerLayer' is to be constructed.
          *
          * Container layers will not be rendered in any fashion and instead are used
@@ -2066,7 +2082,10 @@ public final class SurfaceControl implements Parcelable {
         public static final NativeAllocationRegistry sRegistry = new NativeAllocationRegistry(
                 Transaction.class.getClassLoader(),
                 nativeGetNativeTransactionFinalizer(), 512);
-        private long mNativeObject;
+        /**
+         * @hide
+         */
+        public long mNativeObject;
 
         private final ArrayMap<SurfaceControl, Point> mResizedSurfaces = new ArrayMap<>();
         Runnable mFreeNativeResources;
diff --git a/core/java/android/view/ViewRootImpl.java b/core/java/android/view/ViewRootImpl.java
index fedd6fbe56ed..a6087be26abc 100644
--- a/core/java/android/view/ViewRootImpl.java
+++ b/core/java/android/view/ViewRootImpl.java
@@ -45,6 +45,7 @@ import android.content.res.CompatibilityInfo;
 import android.content.res.Configuration;
 import android.content.res.Resources;
 import android.content.res.TypedArray;
+import android.graphics.BLASTBufferQueue;
 import android.graphics.Canvas;
 import android.graphics.Color;
 import android.graphics.FrameInfo;
@@ -170,6 +171,8 @@ public final class ViewRootImpl implements ViewParent,
      */
     private static final boolean MT_RENDERER_AVAILABLE = true;
 
+    private static final boolean USE_BLAST_BUFFERQUEUE = false;
+
     /**
      * If set to 2, the view system will switch from using rectangles retrieved from window to
      * dispatch to the view hierarchy to using {@link InsetsController}, that derives the insets
@@ -475,6 +478,9 @@ public final class ViewRootImpl implements ViewParent,
     @UnsupportedAppUsage
     public final Surface mSurface = new Surface();
     private final SurfaceControl mSurfaceControl = new SurfaceControl();
+    private SurfaceControl mBlastSurfaceControl;
+
+    private BLASTBufferQueue mBlastBufferQueue;
 
     /**
      * Transaction object that can be used to synchronize child SurfaceControl changes with
@@ -1282,6 +1288,11 @@ public final class ViewRootImpl implements ViewParent,
             }
             mWindowAttributes.privateFlags |= compatibleWindowFlag;
 
+            if (USE_BLAST_BUFFERQUEUE) {
+                mWindowAttributes.privateFlags =
+                    WindowManager.LayoutParams.PRIVATE_FLAG_USE_BLAST;
+            }
+
             if (mWindowAttributes.preservePreviousSurfaceInsets) {
                 // Restore old surface insets.
                 mWindowAttributes.surfaceInsets.set(
@@ -1629,6 +1640,29 @@ public final class ViewRootImpl implements ViewParent,
         return mBoundsLayer;
     }
 
+    Surface getOrCreateBLASTSurface(int width, int height) {
+        if (mSurfaceControl == null || !mSurfaceControl.isValid()) {
+            return null;
+        }
+        if (mBlastSurfaceControl == null) {
+            mBlastSurfaceControl = new SurfaceControl.Builder(mSurfaceSession)
+            .setParent(mSurfaceControl)
+            .setName("BLAST")
+            .setBLASTLayer()
+            .build();
+            mBlastBufferQueue = new BLASTBufferQueue(
+                mBlastSurfaceControl, width, height);
+
+        }
+        mBlastBufferQueue.update(mSurfaceControl, width, height);
+
+        mTransaction.show(mBlastSurfaceControl)
+            .reparent(mBlastSurfaceControl, mSurfaceControl)
+            .apply();
+
+        return mBlastBufferQueue.getSurface();
+    }
+    
     private void setBoundsLayerCrop() {
         // mWinFrame is already adjusted for surface insets. So offset it and use it as
         // the cropping bounds.
@@ -1658,6 +1692,13 @@ public final class ViewRootImpl implements ViewParent,
         }
         mSurface.release();
         mSurfaceControl.release();
+
+        if (mBlastBufferQueue != null) {
+            mTransaction.remove(mBlastSurfaceControl).apply();
+            mBlastSurfaceControl = null;
+            // We should probably add an explicit dispose.
+            mBlastBufferQueue = null;
+        }
     }
 
     /**
@@ -2413,10 +2454,9 @@ public final class ViewRootImpl implements ViewParent,
                     // will be transparent
                     if (mAttachInfo.mThreadedRenderer != null) {
                         try {
-                            hwInitialized = mAttachInfo.mThreadedRenderer.initialize(
-                                    mSurface);
+                            hwInitialized = mAttachInfo.mThreadedRenderer.initialize(mSurface);
                             if (hwInitialized && (host.mPrivateFlags
-                                    & View.PFLAG_REQUEST_TRANSPARENT_REGIONS) == 0) {
+                                            & View.PFLAG_REQUEST_TRANSPARENT_REGIONS) == 0) {
                                 // Don't pre-allocate if transparent regions
                                 // are requested as they may not be needed
                                 mAttachInfo.mThreadedRenderer.allocateBuffers();
@@ -7139,7 +7179,13 @@ public final class ViewRootImpl implements ViewParent,
                 mPendingStableInsets, mPendingOutsets, mPendingBackDropFrame, mPendingDisplayCutout,
                 mPendingMergedConfiguration, mSurfaceControl, mTempInsets);
         if (mSurfaceControl.isValid()) {
-            mSurface.copyFrom(mSurfaceControl);
+            if (USE_BLAST_BUFFERQUEUE == false) {
+                mSurface.copyFrom(mSurfaceControl);
+            } else { 
+                mSurface.transferFrom(getOrCreateBLASTSurface(
+                    (int) (mView.getMeasuredWidth() * appScale + 0.5f),
+                    (int) (mView.getMeasuredHeight() * appScale + 0.5f)));
+            }
         } else {
             destroySurface();
         }
diff --git a/core/java/android/view/WindowManager.java b/core/java/android/view/WindowManager.java
index 001ab6650551..4a6ef987a642 100644
--- a/core/java/android/view/WindowManager.java
+++ b/core/java/android/view/WindowManager.java
@@ -1834,6 +1834,13 @@ public interface WindowManager extends ViewManager {
         public static final int PRIVATE_FLAG_COLOR_SPACE_AGNOSTIC = 0x01000000;
 
         /**
+         * Flag to request creation of a BLAST (Buffer as LayerState) Layer.
+         * If not specified the client will receive a BufferQueue layer.
+         * @hide
+         */
+        public static final int PRIVATE_FLAG_USE_BLAST = 0x02000000;
+
+        /**
          * An internal annotation for flags that can be specified to {@link #softInputMode}.
          *
          * @hide