From 970112231e887c8a14441ec4fed55342e019fc8c Mon Sep 17 00:00:00 2001
From: Mathias Agopian <mathias@google.com>
Date: Tue, 28 Jul 2009 10:57:27 -0700
Subject: fix [2017532] Partial Update leaves residual image.

---
 libs/surfaceflinger/SurfaceFlinger.cpp | 21 ++++++++++++++-------
 libs/surfaceflinger/SurfaceFlinger.h   |  1 +
 2 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/libs/surfaceflinger/SurfaceFlinger.cpp b/libs/surfaceflinger/SurfaceFlinger.cpp
index fb256638cd..97dfeccae1 100644
--- a/libs/surfaceflinger/SurfaceFlinger.cpp
+++ b/libs/surfaceflinger/SurfaceFlinger.cpp
@@ -691,9 +691,14 @@ void SurfaceFlinger::handleTransaction(uint32_t transactionFlags)
 
         // some layers might have been removed, so
         // we need to update the regions they're exposing.
-        size_t c = mRemovedLayers.size();
+        const SortedVector<LayerBase*>& removedLayers(mRemovedLayers);
+        size_t c = removedLayers.size();
         if (c) {
             mVisibleRegionsDirty = true;
+            while (c--) {
+                mDirtyRegionRemovedLayer.orSelf(
+                        removedLayers[c]->visibleRegionScreen);
+            }
         }
 
         const LayerVector& currentLayers = mCurrentState.layersSortedByZ;
@@ -733,17 +738,15 @@ void SurfaceFlinger::computeVisibleRegions(
         layer->validateVisibility(planeTransform);
 
         // start with the whole surface at its current location
-        const Layer::State& s = layer->drawingState();
-        const Rect bounds(layer->visibleBounds());
+        const Layer::State& s(layer->drawingState());
 
         // handle hidden surfaces by setting the visible region to empty
         Region opaqueRegion;
         Region visibleRegion;
         Region coveredRegion;
-        if (UNLIKELY((s.flags & ISurfaceComposer::eLayerHidden) || !s.alpha)) {
-            visibleRegion.clear();
-        } else {
+        if (LIKELY(!(s.flags & ISurfaceComposer::eLayerHidden) && s.alpha)) {
             const bool translucent = layer->needsBlending();
+            const Rect bounds(layer->visibleBounds());
             visibleRegion.set(bounds);
             coveredRegion = visibleRegion;
 
@@ -790,12 +793,16 @@ void SurfaceFlinger::computeVisibleRegions(
         layer->setVisibleRegion(visibleRegion);
         layer->setCoveredRegion(coveredRegion);
 
-        // If a secure layer is partially visible, lockdown the screen!
+        // If a secure layer is partially visible, lock-down the screen!
         if (layer->isSecure() && !visibleRegion.isEmpty()) {
             secureFrameBuffer = true;
         }
     }
 
+    // invalidate the areas where a layer was removed
+    dirtyRegion.orSelf(mDirtyRegionRemovedLayer);
+    mDirtyRegionRemovedLayer.clear();
+
     mSecureFrameBuffer = secureFrameBuffer;
     opaqueRegion = aboveOpaqueLayers;
 }
diff --git a/libs/surfaceflinger/SurfaceFlinger.h b/libs/surfaceflinger/SurfaceFlinger.h
index 15913f2318..0d63e1db6a 100644
--- a/libs/surfaceflinger/SurfaceFlinger.h
+++ b/libs/surfaceflinger/SurfaceFlinger.h
@@ -351,6 +351,7 @@ private:
                 // Can only accessed from the main thread, these members
                 // don't need synchronization
                 Region                      mDirtyRegion;
+                Region                      mDirtyRegionRemovedLayer;
                 Region                      mInvalidRegion;
                 Region                      mWormholeRegion;
                 Client*                     mLastScheduledBroadcast;
-- 
cgit v1.2.3-59-g8ed1b