commit 82364e3cea0bf88fa8147766433329b3dd5148b8
author Robert Carr <racarr@google.com> Sun May 15 11:27:47 2016 -0700
committer Robert Carr <racarr@google.com> Tue Jun 07 11:42:32 2016 -0700
tree 8c02d094dc655a958de9f941c38325348c7e1b3c
parent d224e6111bf4532fb1c1fc021c20285b38bc80ec

SurfaceFlinger: Add mode to apply position with resize.

For some cases, like scaled windows with shadows,
we need to be able to apply the position concurrent with
window resize. This is because the scaling of the shadows causes
the top left coordinate of the non shadow surface content
to change before and after the resize.

Bug: 28899837
Change-Id: I522eacfbbcd79707dc1e5ab71901a263b3004ba9

services/surfaceflinger/Layer.cpp

diff --git a/services/surfaceflinger/Layer.cpp b/services/surfaceflinger/Layer.cpp
index b5d3262..0247723 100644
--- a/services/surfaceflinger/Layer.cpp
+++ b/services/surfaceflinger/Layer.cpp
@@ -95,7 +95,8 @@
         mQueueItems(),
         mLastFrameNumberReceived(0),
         mUpdateTexImageFailed(false),
-        mAutoRefresh(false)
+        mAutoRefresh(false),
+        mFreezePositionUpdates(false)
 {
 #ifdef USE_HWC2
     ALOGV("Creating Layer %s", name.string());
@@ -1415,11 +1416,9 @@
                 c.requested.w, c.requested.h);
     }
 
+    const bool resizePending = (c.requested.w != c.active.w) ||
+            (c.requested.h != c.active.h);
     if (!isFixedSize()) {
-
-        const bool resizePending = (c.requested.w != c.active.w) ||
-                                   (c.requested.h != c.active.h);
-
         if (resizePending && mSidebandStream == NULL) {
             // don't let Layer::doTransaction update the drawing state
             // if we have a pending resize, unless we are in fixed-size mode.
@@ -1443,8 +1442,16 @@
     if (flags & eDontUpdateGeometryState)  {
     } else {
         Layer::State& editCurrentState(getCurrentState());
-        editCurrentState.active = editCurrentState.requested;
-        c.active = c.requested;
+        if (mFreezePositionUpdates) {
+            float tx = c.active.transform.tx();
+            float ty = c.active.transform.ty();
+            c.active = c.requested;
+            c.active.transform.set(tx, ty);
+            editCurrentState.active = c.active;
+        } else {
+            editCurrentState.active = editCurrentState.requested;
+            c.active = c.requested;
+        }
     }
 
     if (s.active != c.active) {
@@ -1491,7 +1498,7 @@
     return android_atomic_or(flags, &mTransactionFlags);
 }
 
-bool Layer::setPosition(float x, float y) {
+bool Layer::setPosition(float x, float y, bool immediate) {
     if (mCurrentState.requested.transform.tx() == x && mCurrentState.requested.transform.ty() == y)
         return false;
     mCurrentState.sequence++;
@@ -1500,12 +1507,16 @@
     // we want to apply the position portion of the transform matrix immediately,
     // but still delay scaling when resizing a SCALING_MODE_FREEZE layer.
     mCurrentState.requested.transform.set(x, y);
-    mCurrentState.active.transform.set(x, y);
+    if (immediate && !mFreezePositionUpdates) {
+        mCurrentState.active.transform.set(x, y);
+    }
+    mFreezePositionUpdates = mFreezePositionUpdates || !immediate;
 
     mCurrentState.modified = true;
     setTransactionFlags(eTransactionNeeded);
     return true;
 }
+
 bool Layer::setLayer(uint32_t z) {
     if (mCurrentState.z == z)
         return false;
@@ -1585,6 +1596,7 @@
     if (scalingMode == mOverrideScalingMode)
         return false;
     mOverrideScalingMode = scalingMode;
+    setTransactionFlags(eTransactionNeeded);
     return true;
 }
 
@@ -2004,6 +2016,7 @@
             if (bufWidth != uint32_t(oldActiveBuffer->width) ||
                 bufHeight != uint32_t(oldActiveBuffer->height)) {
                 recomputeVisibleRegions = true;
+                mFreezePositionUpdates = false;
             }
         }