Merge "Check if the buffer is actually being scaled instead of only checking scaling mode"
diff --git a/services/surfaceflinger/BufferLayer.cpp b/services/surfaceflinger/BufferLayer.cpp
index 9c3fdbb..d302f98 100644
--- a/services/surfaceflinger/BufferLayer.cpp
+++ b/services/surfaceflinger/BufferLayer.cpp
@@ -204,8 +204,8 @@
     layer.frameNumber = mCurrentFrameNumber;
     layer.bufferId = mBufferInfo.mBuffer ? mBufferInfo.mBuffer->getId() : 0;
 
-    // TODO: we could be more subtle with isFixedSize()
-    const bool useFiltering = targetSettings.needsFiltering || mNeedsFiltering || isFixedSize();
+    const bool useFiltering =
+            targetSettings.needsFiltering || mNeedsFiltering || bufferNeedsFiltering();
 
     // Query the texture matrix given our current filtering mode.
     float textureMatrix[16];
@@ -822,6 +822,10 @@
     }
 }
 
+bool BufferLayer::bufferNeedsFiltering() const {
+    return isFixedSize();
+}
+
 } // namespace android
 
 #if defined(__gl_h_)
diff --git a/services/surfaceflinger/BufferLayer.h b/services/surfaceflinger/BufferLayer.h
index e6a0f81..deaf846 100644
--- a/services/surfaceflinger/BufferLayer.h
+++ b/services/surfaceflinger/BufferLayer.h
@@ -115,6 +115,10 @@
 
     ui::Transform::RotationFlags getTransformHint() const override { return mTransformHint; }
 
+    // Returns true if the transformed buffer size does not match the layer size and we need
+    // to apply filtering.
+    virtual bool bufferNeedsFiltering() const;
+
 protected:
     struct BufferInfo {
         nsecs_t mDesiredPresentTime;
diff --git a/services/surfaceflinger/BufferStateLayer.cpp b/services/surfaceflinger/BufferStateLayer.cpp
index 6f344c7..f851514 100644
--- a/services/surfaceflinger/BufferStateLayer.cpp
+++ b/services/surfaceflinger/BufferStateLayer.cpp
@@ -744,6 +744,31 @@
                                         static_cast<float>(s.active.transform.ty() + s.active.h)),
                               radius);
 }
+
+bool BufferStateLayer::bufferNeedsFiltering() const {
+    const State& s(getDrawingState());
+    if (!s.buffer) {
+        return false;
+    }
+
+    uint32_t bufferWidth = s.buffer->width;
+    uint32_t bufferHeight = s.buffer->height;
+
+    // Undo any transformations on the buffer and return the result.
+    if (s.transform & ui::Transform::ROT_90) {
+        std::swap(bufferWidth, bufferHeight);
+    }
+
+    if (s.transformToDisplayInverse) {
+        uint32_t invTransform = DisplayDevice::getPrimaryDisplayRotationFlags();
+        if (invTransform & ui::Transform::ROT_90) {
+            std::swap(bufferWidth, bufferHeight);
+        }
+    }
+
+    const Rect layerSize{getBounds()};
+    return layerSize.width() != bufferWidth || layerSize.height() != bufferHeight;
+}
 } // namespace android
 
 // TODO(b/129481165): remove the #pragma below and fix conversion issues
diff --git a/services/surfaceflinger/BufferStateLayer.h b/services/surfaceflinger/BufferStateLayer.h
index 4773286..104a13b 100644
--- a/services/surfaceflinger/BufferStateLayer.h
+++ b/services/surfaceflinger/BufferStateLayer.h
@@ -143,6 +143,8 @@
 
     bool willPresentCurrentTransaction() const;
 
+    bool bufferNeedsFiltering() const override;
+
     static const std::array<float, 16> IDENTITY_MATRIX;
 
     std::unique_ptr<renderengine::Image> mTextureImage;