SF: Setup CompositionEngine::Layer

Add a Layer class to CompositionEngine, and modify ColorLayer and
BufferLayer to create them.

Also sets up CompositionEngine::LayerFE as an interface to be
implemented by the SF Layer class.

Test: atest libsurfaceflinger_unittest libcompositionengine_test
Bug: 121291683
Change-Id: I2ed83355e81f36954b034ec60dd1a24c631f4874

24 files changed, 462 insertions, 39 deletions

diff --git a/services/surfaceflinger/BufferLayer.cpp b/services/surfaceflinger/BufferLayer.cpp
index 9662fcd01f..f986329245 100644
--- a/services/surfaceflinger/BufferLayer.cpp
+++ b/services/surfaceflinger/BufferLayer.cpp
@@ -19,40 +19,42 @@
 #define LOG_TAG "BufferLayer"
 #define ATRACE_TAG ATRACE_TAG_GRAPHICS
 
-#include "BufferLayer.h"
-#include "Colorizer.h"
-#include "DisplayDevice.h"
-#include "LayerRejecter.h"
-
-#include "TimeStats/TimeStats.h"
-
-#include <renderengine/RenderEngine.h>
+#include <cmath>
+#include <cstdlib>
+#include <mutex>
 
+#include <compositionengine/CompositionEngine.h>
+#include <compositionengine/Layer.h>
+#include <compositionengine/LayerCreationArgs.h>
+#include <cutils/compiler.h>
+#include <cutils/native_handle.h>
+#include <cutils/properties.h>
 #include <gui/BufferItem.h>
 #include <gui/BufferQueue.h>
 #include <gui/LayerDebugInfo.h>
 #include <gui/Surface.h>
-
+#include <renderengine/RenderEngine.h>
 #include <ui/DebugUtils.h>
-
 #include <utils/Errors.h>
 #include <utils/Log.h>
 #include <utils/NativeHandle.h>
 #include <utils/StopWatch.h>
 #include <utils/Trace.h>
 
-#include <cutils/compiler.h>
-#include <cutils/native_handle.h>
-#include <cutils/properties.h>
+#include "BufferLayer.h"
+#include "Colorizer.h"
+#include "DisplayDevice.h"
+#include "LayerRejecter.h"
 
-#include <math.h>
-#include <stdlib.h>
-#include <mutex>
+#include "TimeStats/TimeStats.h"
 
 namespace android {
 
 BufferLayer::BufferLayer(const LayerCreationArgs& args)
-      : Layer(args), mTextureName(args.flinger->getNewTexture()) {
+      : Layer(args),
+        mTextureName(args.flinger->getNewTexture()),
+        mCompositionLayer{mFlinger->getCompositionEngine().createLayer(
+                compositionengine::LayerCreationArgs{this})} {
     ALOGV("Creating Layer %s", args.name.string());
 
     mPremultipliedAlpha = !(args.flags & ISurfaceComposerClient::eNonPremultiplied);
@@ -649,6 +651,10 @@ Rect BufferLayer::getBufferSize(const State& s) const {
     return Rect(bufWidth, bufHeight);
 }
 
+std::shared_ptr<compositionengine::Layer> BufferLayer::getCompositionLayer() const {
+    return mCompositionLayer;
+}
+
 } // namespace android
 
 #if defined(__gl_h_)
diff --git a/services/surfaceflinger/BufferLayer.h b/services/surfaceflinger/BufferLayer.h
index 3fe8ed0920..cc4e6c2bc2 100644
--- a/services/surfaceflinger/BufferLayer.h
+++ b/services/surfaceflinger/BufferLayer.h
@@ -16,35 +16,33 @@
 
 #pragma once
 
-#include "BufferLayerConsumer.h"
-#include "Client.h"
-#include "Layer.h"
-#include "DisplayHardware/HWComposer.h"
-#include "DisplayHardware/HWComposerBufferCache.h"
-#include "FrameTracker.h"
-#include "LayerVector.h"
-#include "MonitoredProducer.h"
-#include "SurfaceFlinger.h"
+#include <sys/types.h>
+#include <cstdint>
+#include <list>
 
 #include <gui/ISurfaceComposerClient.h>
 #include <gui/LayerState.h>
 #include <renderengine/Image.h>
 #include <renderengine/Mesh.h>
 #include <renderengine/Texture.h>
+#include <system/window.h> // For NATIVE_WINDOW_SCALING_MODE_FREEZE
 #include <ui/FrameStats.h>
 #include <ui/GraphicBuffer.h>
 #include <ui/PixelFormat.h>
 #include <ui/Region.h>
-
 #include <utils/RefBase.h>
 #include <utils/String8.h>
 #include <utils/Timers.h>
 
-#include <system/window.h> // For NATIVE_WINDOW_SCALING_MODE_FREEZE
-
-#include <stdint.h>
-#include <sys/types.h>
-#include <list>
+#include "BufferLayerConsumer.h"
+#include "Client.h"
+#include "DisplayHardware/HWComposer.h"
+#include "DisplayHardware/HWComposerBufferCache.h"
+#include "FrameTracker.h"
+#include "Layer.h"
+#include "LayerVector.h"
+#include "MonitoredProducer.h"
+#include "SurfaceFlinger.h"
 
 namespace android {
 
@@ -57,6 +55,8 @@ public:
     // Overriden from Layer
     // -----------------------------------------------------------------------
 public:
+    std::shared_ptr<compositionengine::Layer> getCompositionLayer() const override;
+
     // If we have received a new buffer this frame, we will pass its surface
     // damage down to hardware composer. Otherwise, we must send a region with
     // one empty rect.
@@ -187,6 +187,8 @@ private:
     bool mBufferLatched{false}; // TODO: Use mActiveBuffer?
 
     Rect getBufferSize(const State& s) const override;
+
+    std::shared_ptr<compositionengine::Layer> mCompositionLayer;
 };
 
 } // namespace android
diff --git a/services/surfaceflinger/ColorLayer.cpp b/services/surfaceflinger/ColorLayer.cpp
index 34082c3bed..c2f81c2db0 100644
--- a/services/surfaceflinger/ColorLayer.cpp
+++ b/services/surfaceflinger/ColorLayer.cpp
@@ -22,6 +22,9 @@
 #include <stdlib.h>
 #include <sys/types.h>
 
+#include <compositionengine/CompositionEngine.h>
+#include <compositionengine/Layer.h>
+#include <compositionengine/LayerCreationArgs.h>
 #include <renderengine/RenderEngine.h>
 #include <ui/GraphicBuffer.h>
 #include <utils/Errors.h>
@@ -34,7 +37,10 @@
 namespace android {
 // ---------------------------------------------------------------------------
 
-ColorLayer::ColorLayer(const LayerCreationArgs& args) : Layer(args) {}
+ColorLayer::ColorLayer(const LayerCreationArgs& args)
+      : Layer(args),
+        mCompositionLayer{mFlinger->getCompositionEngine().createLayer(
+                compositionengine::LayerCreationArgs{this})} {}
 
 ColorLayer::~ColorLayer() = default;
 
@@ -113,6 +119,10 @@ void ColorLayer::setPerFrameData(DisplayId displayId, const ui::Transform& trans
     getBE().compositionInfo.hwc.surfaceDamage = surfaceDamageRegion;
 }
 
+std::shared_ptr<compositionengine::Layer> ColorLayer::getCompositionLayer() const {
+    return mCompositionLayer;
+}
+
 // ---------------------------------------------------------------------------
 
 }; // namespace android
diff --git a/services/surfaceflinger/ColorLayer.h b/services/surfaceflinger/ColorLayer.h
index f43fc3ce35..ecaef82070 100644
--- a/services/surfaceflinger/ColorLayer.h
+++ b/services/surfaceflinger/ColorLayer.h
@@ -28,6 +28,8 @@ public:
     explicit ColorLayer(const LayerCreationArgs&);
     ~ColorLayer() override;
 
+    std::shared_ptr<compositionengine::Layer> getCompositionLayer() const override;
+
     virtual const char* getTypeId() const { return "ColorLayer"; }
     bool isVisible() const override;
 
@@ -41,6 +43,9 @@ protected:
     virtual bool prepareClientLayer(const RenderArea& renderArea, const Region& clip,
                                     bool useIdentityTransform, Region& clearRegion,
                                     renderengine::LayerSettings& layer);
+
+private:
+    std::shared_ptr<compositionengine::Layer> mCompositionLayer;
 };
 
 } // namespace android
diff --git a/services/surfaceflinger/CompositionEngine/Android.bp b/services/surfaceflinger/CompositionEngine/Android.bp
index 49fa84a7ec..564bd5b96b 100644
--- a/services/surfaceflinger/CompositionEngine/Android.bp
+++ b/services/surfaceflinger/CompositionEngine/Android.bp
@@ -41,6 +41,7 @@ cc_library {
         "src/DisplayColorProfile.cpp",
         "src/DisplaySurface.cpp",
         "src/DumpHelpers.cpp",
+        "src/Layer.cpp",
         "src/Output.cpp",
         "src/OutputCompositionState.cpp",
         "src/RenderSurface.cpp",
@@ -57,6 +58,8 @@ cc_library {
         "mock/Display.cpp",
         "mock/DisplayColorProfile.cpp",
         "mock/DisplaySurface.cpp",
+        "mock/Layer.cpp",
+        "mock/LayerFE.cpp",
         "mock/Output.cpp",
         "mock/RenderSurface.cpp",
     ],
@@ -77,6 +80,7 @@ cc_test {
         "tests/CompositionEngineTest.cpp",
         "tests/DisplayColorProfileTest.cpp",
         "tests/DisplayTest.cpp",
+        "tests/LayerTest.cpp",
         "tests/MockHWComposer.cpp",
         "tests/OutputTest.cpp",
         "tests/RenderSurfaceTest.cpp",
diff --git a/services/surfaceflinger/CompositionEngine/include/compositionengine/CompositionEngine.h b/services/surfaceflinger/CompositionEngine/include/compositionengine/CompositionEngine.h
index 30cdb49b0d..896f8aaa69 100644
--- a/services/surfaceflinger/CompositionEngine/include/compositionengine/CompositionEngine.h
+++ b/services/surfaceflinger/CompositionEngine/include/compositionengine/CompositionEngine.h
@@ -29,8 +29,10 @@ class RenderEngine;
 namespace compositionengine {
 
 class Display;
+class Layer;
 
 struct DisplayCreationArgs;
+struct LayerCreationArgs;
 
 /**
  * Encapsulates all the interfaces and implementation details for performing
@@ -42,6 +44,7 @@ public:
 
     // Create a composition Display
     virtual std::shared_ptr<Display> createDisplay(DisplayCreationArgs&&) = 0;
+    virtual std::shared_ptr<Layer> createLayer(LayerCreationArgs&&) = 0;
 
     virtual HWComposer& getHwComposer() const = 0;
     virtual void setHwComposer(std::unique_ptr<HWComposer>) = 0;
diff --git a/services/surfaceflinger/CompositionEngine/include/compositionengine/Layer.h b/services/surfaceflinger/CompositionEngine/include/compositionengine/Layer.h
new file mode 100644
index 0000000000..29a7deafce
--- /dev/null
+++ b/services/surfaceflinger/CompositionEngine/include/compositionengine/Layer.h
@@ -0,0 +1,46 @@
+/*
+ * Copyright 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <cstdint>
+
+#include <utils/StrongPointer.h>
+
+namespace android {
+
+typedef int64_t nsecs_t;
+
+namespace compositionengine {
+
+class Display;
+class LayerFE;
+
+/**
+ * A layer contains the output-independent composition state for a front-end
+ * Layer
+ */
+class Layer {
+public:
+    virtual ~Layer();
+
+    // Gets the front-end interface for this layer.  Can return nullptr if the
+    // front-end layer no longer exists.
+    virtual sp<LayerFE> getLayerFE() const = 0;
+};
+
+} // namespace compositionengine
+} // namespace android
diff --git a/services/surfaceflinger/CompositionEngine/include/compositionengine/LayerCreationArgs.h b/services/surfaceflinger/CompositionEngine/include/compositionengine/LayerCreationArgs.h
new file mode 100644
index 0000000000..db3312b6e9
--- /dev/null
+++ b/services/surfaceflinger/CompositionEngine/include/compositionengine/LayerCreationArgs.h
@@ -0,0 +1,35 @@
+/*
+ * Copyright 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <utils/RefBase.h>
+
+namespace android::compositionengine {
+
+class CompositionEngine;
+class LayerFE;
+
+/**
+ * A parameter object for creating Layer instances
+ */
+struct LayerCreationArgs {
+    // A weak pointer to the front-end layer instance that the new layer will
+    // represent.
+    wp<LayerFE> layerFE;
+};
+
+} // namespace android::compositionengine
diff --git a/services/surfaceflinger/CompositionEngine/include/compositionengine/LayerFE.h b/services/surfaceflinger/CompositionEngine/include/compositionengine/LayerFE.h
new file mode 100644
index 0000000000..f9a36241c8
--- /dev/null
+++ b/services/surfaceflinger/CompositionEngine/include/compositionengine/LayerFE.h
@@ -0,0 +1,27 @@
+/*
+ * Copyright 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <utils/RefBase.h>
+
+namespace android::compositionengine {
+
+// Defines the interface used by the CompositionEngine to make requests
+// of the front-end layer
+class LayerFE : public virtual RefBase {};
+
+} // namespace android::compositionengine
diff --git a/services/surfaceflinger/CompositionEngine/include/compositionengine/Output.h b/services/surfaceflinger/CompositionEngine/include/compositionengine/Output.h
index 6be4ad83b8..ab54b5dd44 100644
--- a/services/surfaceflinger/CompositionEngine/include/compositionengine/Output.h
+++ b/services/surfaceflinger/CompositionEngine/include/compositionengine/Output.h
@@ -38,6 +38,8 @@ struct OutputCompositionState;
  */
 class Output {
 public:
+    virtual ~Output();
+
     // Returns true if the output is valid. This is meant to be checked post-
     // construction and prior to use, as not everything is set up by the
     // constructor.
@@ -103,8 +105,6 @@ public:
     virtual bool belongsInOutput(uint32_t layerStackId, bool internalOnly) const = 0;
 
 protected:
-    ~Output() = default;
-
     virtual void setDisplayColorProfile(std::unique_ptr<DisplayColorProfile>) = 0;
     virtual void setRenderSurface(std::unique_ptr<RenderSurface>) = 0;
 };
diff --git a/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/CompositionEngine.h b/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/CompositionEngine.h
index e23c431bc4..b01eb649d8 100644
--- a/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/CompositionEngine.h
+++ b/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/CompositionEngine.h
@@ -27,6 +27,8 @@ public:
 
     std::shared_ptr<compositionengine::Display> createDisplay(
             compositionengine::DisplayCreationArgs&&) override;
+    std::shared_ptr<compositionengine::Layer> createLayer(
+            compositionengine::LayerCreationArgs&&) override;
 
     HWComposer& getHwComposer() const override;
     void setHwComposer(std::unique_ptr<HWComposer>) override;
diff --git a/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/Layer.h b/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/Layer.h
new file mode 100644
index 0000000000..631351b857
--- /dev/null
+++ b/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/Layer.h
@@ -0,0 +1,52 @@
+/*
+ * Copyright 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <memory>
+
+#include <compositionengine/Layer.h>
+#include <utils/RefBase.h>
+#include <utils/StrongPointer.h>
+
+namespace android::compositionengine {
+
+class CompositionEngine;
+class LayerFE;
+
+struct LayerCreationArgs;
+
+namespace impl {
+
+class Display;
+
+class Layer : public compositionengine::Layer {
+public:
+    Layer(const CompositionEngine&, compositionengine::LayerCreationArgs&&);
+    ~Layer() override;
+
+    sp<LayerFE> getLayerFE() const override;
+
+private:
+    const compositionengine::CompositionEngine& mCompositionEngine;
+    const wp<LayerFE> mLayerFE;
+};
+
+std::shared_ptr<compositionengine::Layer> createLayer(const compositionengine::CompositionEngine&,
+                                                      compositionengine::LayerCreationArgs&&);
+
+} // namespace impl
+} // namespace android::compositionengine
diff --git a/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/Output.h b/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/Output.h
index 4be0706af7..1e51c5ecf0 100644
--- a/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/Output.h
+++ b/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/Output.h
@@ -30,7 +30,7 @@ namespace impl {
 class Output : public virtual compositionengine::Output {
 public:
     Output(const CompositionEngine&);
-    virtual ~Output();
+    ~Output() override;
 
     bool isValid() const override;
 
diff --git a/services/surfaceflinger/CompositionEngine/include/compositionengine/mock/CompositionEngine.h b/services/surfaceflinger/CompositionEngine/include/compositionengine/mock/CompositionEngine.h
index 1967666d59..0f57685861 100644
--- a/services/surfaceflinger/CompositionEngine/include/compositionengine/mock/CompositionEngine.h
+++ b/services/surfaceflinger/CompositionEngine/include/compositionengine/mock/CompositionEngine.h
@@ -18,6 +18,7 @@
 
 #include <compositionengine/CompositionEngine.h>
 #include <compositionengine/DisplayCreationArgs.h>
+#include <compositionengine/LayerCreationArgs.h>
 #include <gmock/gmock.h>
 #include <renderengine/RenderEngine.h>
 
@@ -31,6 +32,7 @@ public:
     ~CompositionEngine() override;
 
     MOCK_METHOD1(createDisplay, std::shared_ptr<Display>(DisplayCreationArgs&&));
+    MOCK_METHOD1(createLayer, std::shared_ptr<Layer>(LayerCreationArgs&&));
 
     MOCK_CONST_METHOD0(getHwComposer, HWComposer&());
     MOCK_METHOD1(setHwComposer, void(std::unique_ptr<HWComposer>));
diff --git a/services/surfaceflinger/CompositionEngine/include/compositionengine/mock/Layer.h b/services/surfaceflinger/CompositionEngine/include/compositionengine/mock/Layer.h
new file mode 100644
index 0000000000..a7cc08e117
--- /dev/null
+++ b/services/surfaceflinger/CompositionEngine/include/compositionengine/mock/Layer.h
@@ -0,0 +1,33 @@
+/*
+ * Copyright 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <compositionengine/Layer.h>
+#include <compositionengine/LayerFE.h>
+#include <gmock/gmock.h>
+
+namespace android::compositionengine::mock {
+
+class Layer : public compositionengine::Layer {
+public:
+    Layer();
+    virtual ~Layer();
+
+    MOCK_CONST_METHOD0(getLayerFE, sp<LayerFE>());
+};
+
+} // namespace android::compositionengine::mock
diff --git a/services/surfaceflinger/CompositionEngine/include/compositionengine/mock/LayerFE.h b/services/surfaceflinger/CompositionEngine/include/compositionengine/mock/LayerFE.h
new file mode 100644
index 0000000000..92e007081b
--- /dev/null
+++ b/services/surfaceflinger/CompositionEngine/include/compositionengine/mock/LayerFE.h
@@ -0,0 +1,32 @@
+/*
+ * Copyright 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <compositionengine/LayerFE.h>
+#include <gmock/gmock.h>
+
+namespace android::compositionengine::mock {
+
+// Defines the interface used by the CompositionEngine to make requests
+// of the front-end layer.
+class LayerFE : public compositionengine::LayerFE {
+public:
+    LayerFE();
+    virtual ~LayerFE();
+};
+
+} // namespace android::compositionengine::mock
diff --git a/services/surfaceflinger/CompositionEngine/mock/Layer.cpp b/services/surfaceflinger/CompositionEngine/mock/Layer.cpp
new file mode 100644
index 0000000000..08483cb301
--- /dev/null
+++ b/services/surfaceflinger/CompositionEngine/mock/Layer.cpp
@@ -0,0 +1,26 @@
+/*
+ * Copyright 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <compositionengine/mock/Layer.h>
+
+namespace android::compositionengine::mock {
+
+// The Google Mock documentation recommends explicit non-header instantiations
+// for better compile time performance.
+Layer::Layer() = default;
+Layer::~Layer() = default;
+
+} // namespace android::compositionengine::mock
diff --git a/services/surfaceflinger/CompositionEngine/mock/LayerFE.cpp b/services/surfaceflinger/CompositionEngine/mock/LayerFE.cpp
new file mode 100644
index 0000000000..607eaad826
--- /dev/null
+++ b/services/surfaceflinger/CompositionEngine/mock/LayerFE.cpp
@@ -0,0 +1,26 @@
+/*
+ * Copyright 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <compositionengine/mock/LayerFE.h>
+
+namespace android::compositionengine::mock {
+
+// The Google Mock documentation recommends explicit non-header instantiations
+// for better compile time performance.
+LayerFE::LayerFE() = default;
+LayerFE::~LayerFE() = default;
+
+} // namespace android::compositionengine::mock
diff --git a/services/surfaceflinger/CompositionEngine/src/CompositionEngine.cpp b/services/surfaceflinger/CompositionEngine/src/CompositionEngine.cpp
index 127d729ded..cb08b81627 100644
--- a/services/surfaceflinger/CompositionEngine/src/CompositionEngine.cpp
+++ b/services/surfaceflinger/CompositionEngine/src/CompositionEngine.cpp
@@ -16,6 +16,7 @@
 
 #include <compositionengine/impl/CompositionEngine.h>
 #include <compositionengine/impl/Display.h>
+#include <compositionengine/impl/Layer.h>
 #include <renderengine/RenderEngine.h>
 
 #include "DisplayHardware/HWComposer.h"
@@ -38,6 +39,10 @@ std::shared_ptr<compositionengine::Display> CompositionEngine::createDisplay(
     return compositionengine::impl::createDisplay(*this, std::move(args));
 }
 
+std::shared_ptr<compositionengine::Layer> CompositionEngine::createLayer(LayerCreationArgs&& args) {
+    return compositionengine::impl::createLayer(*this, std::move(args));
+}
+
 HWComposer& CompositionEngine::getHwComposer() const {
     return *mHwComposer.get();
 }
diff --git a/services/surfaceflinger/CompositionEngine/src/Layer.cpp b/services/surfaceflinger/CompositionEngine/src/Layer.cpp
new file mode 100644
index 0000000000..aaa758ea6f
--- /dev/null
+++ b/services/surfaceflinger/CompositionEngine/src/Layer.cpp
@@ -0,0 +1,46 @@
+/*
+ * Copyright 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <compositionengine/CompositionEngine.h>
+#include <compositionengine/LayerCreationArgs.h>
+#include <compositionengine/LayerFE.h>
+#include <compositionengine/impl/Layer.h>
+
+namespace android::compositionengine {
+
+Layer::~Layer() = default;
+
+namespace impl {
+
+std::shared_ptr<compositionengine::Layer> createLayer(
+        const compositionengine::CompositionEngine& compositionEngine,
+        compositionengine::LayerCreationArgs&& args) {
+    return std::make_shared<Layer>(compositionEngine, std::move(args));
+}
+
+Layer::Layer(const CompositionEngine& compositionEngine, LayerCreationArgs&& args)
+      : mCompositionEngine(compositionEngine), mLayerFE(args.layerFE) {
+    static_cast<void>(mCompositionEngine); // Temporary use to prevent an unused warning
+}
+
+Layer::~Layer() = default;
+
+sp<LayerFE> Layer::getLayerFE() const {
+    return mLayerFE.promote();
+}
+
+} // namespace impl
+} // namespace android::compositionengine
diff --git a/services/surfaceflinger/CompositionEngine/src/Output.cpp b/services/surfaceflinger/CompositionEngine/src/Output.cpp
index c4d563f798..2d458bfe53 100644
--- a/services/surfaceflinger/CompositionEngine/src/Output.cpp
+++ b/services/surfaceflinger/CompositionEngine/src/Output.cpp
@@ -21,7 +21,11 @@
 #include <compositionengine/impl/Output.h>
 #include <ui/DebugUtils.h>
 
-namespace android::compositionengine::impl {
+namespace android::compositionengine {
+
+Output::~Output() = default;
+
+namespace impl {
 
 Output::Output(const CompositionEngine& compositionEngine)
       : mCompositionEngine(compositionEngine) {}
@@ -182,4 +186,5 @@ void Output::dirtyEntireOutput() {
     mState.dirtyRegion.set(mState.bounds);
 }
 
-} // namespace android::compositionengine::impl
+} // namespace impl
+} // namespace android::compositionengine
diff --git a/services/surfaceflinger/CompositionEngine/tests/LayerTest.cpp b/services/surfaceflinger/CompositionEngine/tests/LayerTest.cpp
new file mode 100644
index 0000000000..26115a344e
--- /dev/null
+++ b/services/surfaceflinger/CompositionEngine/tests/LayerTest.cpp
@@ -0,0 +1,45 @@
+/*
+ * Copyright 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <gtest/gtest.h>
+
+#include <compositionengine/LayerCreationArgs.h>
+#include <compositionengine/impl/Layer.h>
+#include <compositionengine/mock/CompositionEngine.h>
+#include <compositionengine/mock/LayerFE.h>
+
+namespace android::compositionengine {
+namespace {
+
+using testing::StrictMock;
+
+class LayerTest : public testing::Test {
+public:
+    ~LayerTest() override = default;
+
+    StrictMock<mock::CompositionEngine> mCompositionEngine;
+    sp<LayerFE> mLayerFE = new StrictMock<mock::LayerFE>();
+    impl::Layer mLayer{mCompositionEngine, LayerCreationArgs{mLayerFE}};
+};
+
+/* ------------------------------------------------------------------------
+ * Basic construction
+ */
+
+TEST_F(LayerTest, canInstantiateLayer) {}
+
+} // namespace
+} // namespace android::compositionengine
diff --git a/services/surfaceflinger/Layer.cpp b/services/surfaceflinger/Layer.cpp
index 619964ffbb..f49733bb08 100644
--- a/services/surfaceflinger/Layer.cpp
+++ b/services/surfaceflinger/Layer.cpp
@@ -2227,6 +2227,10 @@ bool Layer::hasInput() const {
     return mDrawingState.inputInfo.token != nullptr;
 }
 
+std::shared_ptr<compositionengine::Layer> Layer::getCompositionLayer() const {
+    return nullptr;
+}
+
 // ---------------------------------------------------------------------------
 
 }; // namespace android
diff --git a/services/surfaceflinger/Layer.h b/services/surfaceflinger/Layer.h
index 00e1a6ff56..c9989c9910 100644
--- a/services/surfaceflinger/Layer.h
+++ b/services/surfaceflinger/Layer.h
@@ -19,6 +19,7 @@
 
 #include <sys/types.h>
 
+#include <compositionengine/LayerFE.h>
 #include <gui/BufferQueue.h>
 #include <gui/ISurfaceComposerClient.h>
 #include <gui/LayerState.h>
@@ -68,6 +69,10 @@ class SurfaceFlinger;
 class LayerDebugInfo;
 class LayerBE;
 
+namespace compositionengine {
+class Layer;
+}
+
 namespace impl {
 class SurfaceInterceptor;
 }
@@ -87,7 +92,7 @@ struct LayerCreationArgs {
     uint32_t flags;
 };
 
-class Layer : public virtual RefBase {
+class Layer : public virtual compositionengine::LayerFE {
     static std::atomic<int32_t> sSequence;
 
 public:
@@ -326,6 +331,8 @@ public:
     // visually.
     bool isLegacyDataSpace() const;
 
+    virtual std::shared_ptr<compositionengine::Layer> getCompositionLayer() const;
+
     // If we have received a new buffer this frame, we will pass its surface
     // damage down to hardware composer. Otherwise, we must send a region with
     // one empty rect.