commit 501ff9acfe9dd656c1fb6d82ec0533c3244fd88b
author John Reck <jreck@google.com> Fri Jun 17 12:57:12 2016 -0700
committer John Reck <jreck@google.com> Fri Jun 17 20:44:43 2016 +0000
tree c71f77127da361e21665c127f6c880c7cc65c4ab
parent 6bc33b07f43b6568be9920905083c20b879a97b1

Avoid re-calculating vsync mid-frame

Fixes: 29072773

By using computeFrameTime AnimationContext would
potentially end up modifying the latest vsync if
a very-slow frame was received from the UI thread.

This could potentially desync animations that were
RT & UI thread 'synchronized', but more significantly
it would confuse the swap chain which tries to only
draw one frame per vsync causing unneccessary frame
drops.

Change-Id: Ibd2ec3157ce32fee1eec8d56837c45a35e622895

libs/hwui/AnimationContext.cpp

diff --git a/libs/hwui/AnimationContext.cpp b/libs/hwui/AnimationContext.cpp
index 097be08..5759ccd 100644
--- a/libs/hwui/AnimationContext.cpp
+++ b/libs/hwui/AnimationContext.cpp
@@ -63,7 +63,7 @@
         mCurrentFrameAnimations.mNextHandle = head;
         head->mPreviousHandle = &mCurrentFrameAnimations;
     }
-    mFrameTimeMs = mClock.computeFrameTimeMs();
+    mFrameTimeMs = ns2ms(mClock.latestVsync());
 }
 
 void AnimationContext::runRemainingAnimations(TreeInfo& info) {