5 files changed, 12 insertions, 2 deletions
diff --git a/services/surfaceflinger/DisplayDevice.cpp b/services/surfaceflinger/DisplayDevice.cpp
index 62cc92a..330e09d 100644
--- a/services/surfaceflinger/DisplayDevice.cpp
+++ b/services/surfaceflinger/DisplayDevice.cpp
@@ -397,6 +397,10 @@ void DisplayDevice::updateGeometryTransform() {
         // Apply the logical translation, scale to physical size, apply the
         // physical translation and finally rotate to the physical orientation.
         mGlobalTransform = R * TP * S * TL;
+
+        const uint8_t type = mGlobalTransform.getType();
+        mNeedsFiltering = (!mGlobalTransform.preserveRects() ||
+                (type >= Transform::SCALE));
     }
 }
 
diff --git a/services/surfaceflinger/DisplayDevice.h b/services/surfaceflinger/DisplayDevice.h
index c9d21e4..d83625a 100644
--- a/services/surfaceflinger/DisplayDevice.h
+++ b/services/surfaceflinger/DisplayDevice.h
@@ -101,6 +101,7 @@ public:
     const Transform&        getTransform() const { return mGlobalTransform; }
     const Rect&             getViewport() const { return mViewport; }
     const Rect&             getFrame() const { return mFrame; }
+    bool                    needsFiltering() const { return mNeedsFiltering; }
 
     uint32_t                getLayerStack() const { return mLayerStack; }
     int32_t                 getDisplayType() const { return mType; }
@@ -195,6 +196,7 @@ private:
     Rect mViewport;
     Rect mFrame;
     Transform mGlobalTransform;
+    bool mNeedsFiltering;
 };
 
 }; // namespace android
diff --git a/services/surfaceflinger/Layer.cpp b/services/surfaceflinger/Layer.cpp
index 3d79baf..41c4963 100644
--- a/services/surfaceflinger/Layer.cpp
+++ b/services/surfaceflinger/Layer.cpp
@@ -344,7 +344,7 @@ void Layer::onDraw(const sp<const DisplayDevice>& hw, const Region& clip) const
 
     if (!isProtected()) {
         // TODO: we could be more subtle with isFixedSize()
-        const bool useFiltering = getFiltering() || needsFiltering() || isFixedSize();
+        const bool useFiltering = getFiltering() || needsFiltering(hw) || isFixedSize();
 
         // Query the texture matrix given our current filtering mode.
         float textureMatrix[16];
diff --git a/services/surfaceflinger/LayerBase.cpp b/services/surfaceflinger/LayerBase.cpp
index 99cb8f3..5ae0ee0 100644
--- a/services/surfaceflinger/LayerBase.cpp
+++ b/services/surfaceflinger/LayerBase.cpp
@@ -87,6 +87,10 @@ void LayerBase::initStates(uint32_t w, uint32_t h, uint32_t flags)
     mDrawingState = mCurrentState;
 }
 
+bool LayerBase::needsFiltering(const sp<const DisplayDevice>& hw) const {
+    return mNeedsFiltering || hw->needsFiltering();
+}
+
 void LayerBase::commitTransaction() {
     mDrawingState = mCurrentState;
 }
diff --git a/services/surfaceflinger/LayerBase.h b/services/surfaceflinger/LayerBase.h
index 9994994..0df41ca 100644
--- a/services/surfaceflinger/LayerBase.h
+++ b/services/surfaceflinger/LayerBase.h
@@ -197,7 +197,7 @@ public:
     /**
      * needsLinearFiltering - true if this surface's state requires filtering
      */
-    virtual bool needsFiltering() const { return mNeedsFiltering; }
+    virtual bool needsFiltering(const sp<const DisplayDevice>& hw) const;
 
     /**
      * isSecure - true if this surface is secure, that is if it prevents