From 81d0e61a04b9ee92d1dbc5353f8c18b605549cf3 Mon Sep 17 00:00:00 2001
From: Jerry Chang <chenghsiuchang@google.com>
Date: Fri, 10 Jun 2022 07:16:42 +0000
Subject: [PATCH] Reduce jittering while dragging divider bar

Set vsync id to transactions moving divider bar surface, so those
transactions won't be committed together and result to empty frame while
dragging the divider bar.

Bug: 230050092
Test: manual dump and verified with perfetto trace
Change-Id: Id570e80a908a07113b8e4bd77f38c05e3eee1d0c
---
 .../shell/splitscreen/StageCoordinator.java   | 22 +++++++++++++------
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/StageCoordinator.java b/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/StageCoordinator.java
index 7ea32a6d8f86d..41e23647a6a47 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/StageCoordinator.java
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/StageCoordinator.java
@@ -76,6 +76,7 @@ import android.os.IBinder;
 import android.os.RemoteException;
 import android.util.Log;
 import android.util.Slog;
+import android.view.Choreographer;
 import android.view.IRemoteAnimationFinishedCallback;
 import android.view.IRemoteAnimationRunner;
 import android.view.RemoteAnimationAdapter;
@@ -1124,6 +1125,7 @@ class StageCoordinator implements SplitLayout.SplitLayoutHandler,
                     mDividerFadeInAnimator.cancel();
                     return;
                 }
+                transaction.setFrameTimelineVsync(Choreographer.getInstance().getVsyncId());
                 transaction.setAlpha(dividerLeash, (float) animation.getAnimatedValue());
                 transaction.apply();
             });
@@ -1216,17 +1218,23 @@ class StageCoordinator implements SplitLayout.SplitLayoutHandler,
 
     @Override
     public void onLayoutPositionChanging(SplitLayout layout) {
-        mSyncQueue.runInSync(t -> updateSurfaceBounds(layout, t, false /* applyResizingOffset */));
+        final SurfaceControl.Transaction t = mTransactionPool.acquire();
+        t.setFrameTimelineVsync(Choreographer.getInstance().getVsyncId());
+        updateSurfaceBounds(layout, t, false /* applyResizingOffset */);
+        t.apply();
+        mTransactionPool.release(t);
     }
 
     @Override
     public void onLayoutSizeChanging(SplitLayout layout) {
-        mSyncQueue.runInSync(t -> {
-            setResizingSplits(true /* resizing */);
-            updateSurfaceBounds(layout, t, true /* applyResizingOffset */);
-            mMainStage.onResizing(getMainStageBounds(), t);
-            mSideStage.onResizing(getSideStageBounds(), t);
-        });
+        final SurfaceControl.Transaction t = mTransactionPool.acquire();
+        t.setFrameTimelineVsync(Choreographer.getInstance().getVsyncId());
+        setResizingSplits(true /* resizing */);
+        updateSurfaceBounds(layout, t, true /* applyResizingOffset */);
+        mMainStage.onResizing(getMainStageBounds(), t);
+        mSideStage.onResizing(getSideStageBounds(), t);
+        t.apply();
+        mTransactionPool.release(t);
     }
 
     @Override