SF: Make ExternalTexture mockable

Expose GraphicBuffer properties via ExternalTexture class. Within
SurfaceFlinger access the buffer via this proxy interface.
This allows us to inject and mock GraphicBuffers as needed.
Specifically this will be used to recreate layer state from
transaction traces.

Test: compiles
Bug: 200284593

Change-Id: I2e7f6bee28314b70eac477cfadbf9f94c4d70339
diff --git a/services/surfaceflinger/BufferLayer.cpp b/services/surfaceflinger/BufferLayer.cpp
index d61a4cb..649138a 100644
--- a/services/surfaceflinger/BufferLayer.cpp
+++ b/services/surfaceflinger/BufferLayer.cpp
@@ -164,7 +164,7 @@
     const bool blackOutLayer = (isProtected() && !targetSettings.supportsProtectedContent) ||
             ((isSecure() || isProtected()) && !targetSettings.isSecure);
     const bool bufferCanBeUsedAsHwTexture =
-            mBufferInfo.mBuffer->getBuffer()->getUsage() & GraphicBuffer::USAGE_HW_TEXTURE;
+            mBufferInfo.mBuffer->getUsage() & GraphicBuffer::USAGE_HW_TEXTURE;
     compositionengine::LayerFE::LayerSettings& layer = *result;
     if (blackOutLayer || !bufferCanBeUsedAsHwTexture) {
         ALOGE_IF(!bufferCanBeUsedAsHwTexture, "%s is blacked out as buffer is not gpu readable",
@@ -201,7 +201,7 @@
     }
     layer.source.buffer.maxLuminanceNits = maxLuminance;
     layer.frameNumber = mCurrentFrameNumber;
-    layer.bufferId = mBufferInfo.mBuffer ? mBufferInfo.mBuffer->getBuffer()->getId() : 0;
+    layer.bufferId = mBufferInfo.mBuffer ? mBufferInfo.mBuffer->getId() : 0;
 
     const bool useFiltering =
             targetSettings.needsFiltering || mNeedsFiltering || bufferNeedsFiltering();
@@ -436,7 +436,7 @@
 
 void BufferLayer::gatherBufferInfo() {
     mBufferInfo.mPixelFormat =
-            !mBufferInfo.mBuffer ? PIXEL_FORMAT_NONE : mBufferInfo.mBuffer->getBuffer()->format;
+            !mBufferInfo.mBuffer ? PIXEL_FORMAT_NONE : mBufferInfo.mBuffer->getPixelFormat();
     mBufferInfo.mFrameLatencyNeeded = true;
 }
 
@@ -533,10 +533,10 @@
     }
 
     if (oldBufferInfo.mBuffer != nullptr) {
-        uint32_t bufWidth = mBufferInfo.mBuffer->getBuffer()->getWidth();
-        uint32_t bufHeight = mBufferInfo.mBuffer->getBuffer()->getHeight();
-        if (bufWidth != uint32_t(oldBufferInfo.mBuffer->getBuffer()->width) ||
-            bufHeight != uint32_t(oldBufferInfo.mBuffer->getBuffer()->height)) {
+        uint32_t bufWidth = mBufferInfo.mBuffer->getWidth();
+        uint32_t bufHeight = mBufferInfo.mBuffer->getHeight();
+        if (bufWidth != oldBufferInfo.mBuffer->getWidth() ||
+            bufHeight != oldBufferInfo.mBuffer->getHeight()) {
             recomputeVisibleRegions = true;
         }
     }
@@ -558,7 +558,7 @@
 
 bool BufferLayer::isProtected() const {
     return (mBufferInfo.mBuffer != nullptr) &&
-            (mBufferInfo.mBuffer->getBuffer()->getUsage() & GRALLOC_USAGE_PROTECTED);
+            (mBufferInfo.mBuffer->getUsage() & GRALLOC_USAGE_PROTECTED);
 }
 
 // As documented in libhardware header, formats in the range
@@ -638,8 +638,8 @@
         return Rect::INVALID_RECT;
     }
 
-    uint32_t bufWidth = mBufferInfo.mBuffer->getBuffer()->getWidth();
-    uint32_t bufHeight = mBufferInfo.mBuffer->getBuffer()->getHeight();
+    uint32_t bufWidth = mBufferInfo.mBuffer->getWidth();
+    uint32_t bufHeight = mBufferInfo.mBuffer->getHeight();
 
     // Undo any transformations on the buffer and return the result.
     if (mBufferInfo.mTransform & ui::Transform::ROT_90) {
@@ -670,8 +670,8 @@
         return parentBounds;
     }
 
-    uint32_t bufWidth = mBufferInfo.mBuffer->getBuffer()->getWidth();
-    uint32_t bufHeight = mBufferInfo.mBuffer->getBuffer()->getHeight();
+    uint32_t bufWidth = mBufferInfo.mBuffer->getWidth();
+    uint32_t bufHeight = mBufferInfo.mBuffer->getHeight();
 
     // Undo any transformations on the buffer and return the result.
     if (mBufferInfo.mTransform & ui::Transform::ROT_90) {
@@ -713,7 +713,7 @@
         return mBufferInfo.mCrop;
     } else if (mBufferInfo.mBuffer != nullptr) {
         // otherwise we use the whole buffer
-        return mBufferInfo.mBuffer->getBuffer()->getBounds();
+        return mBufferInfo.mBuffer->getBounds();
     } else {
         // if we don't have a buffer yet, we use an empty/invalid crop
         return Rect();
diff --git a/services/surfaceflinger/BufferLayerConsumer.cpp b/services/surfaceflinger/BufferLayerConsumer.cpp
index c79fa11..9ae45fc 100644
--- a/services/surfaceflinger/BufferLayerConsumer.cpp
+++ b/services/surfaceflinger/BufferLayerConsumer.cpp
@@ -41,6 +41,7 @@
 #include <gui/SurfaceComposerClient.h>
 #include <private/gui/ComposerService.h>
 #include <renderengine/RenderEngine.h>
+#include <renderengine/impl/ExternalTexture.h>
 #include <utils/Log.h>
 #include <utils/String8.h>
 #include <utils/Trace.h>
@@ -208,8 +209,9 @@
         if (mImages[item->mSlot] == nullptr || mImages[item->mSlot]->getBuffer() == nullptr ||
             mImages[item->mSlot]->getBuffer()->getId() != item->mGraphicBuffer->getId()) {
             mImages[item->mSlot] = std::make_shared<
-                    renderengine::ExternalTexture>(item->mGraphicBuffer, mRE,
-                                                   renderengine::ExternalTexture::Usage::READABLE);
+                    renderengine::impl::ExternalTexture>(item->mGraphicBuffer, mRE,
+                                                         renderengine::impl::ExternalTexture::
+                                                                 Usage::READABLE);
         }
     }
 
@@ -462,8 +464,9 @@
         if (oldImage == nullptr || oldImage->getBuffer() == nullptr ||
             oldImage->getBuffer()->getId() != item.mGraphicBuffer->getId()) {
             mImages[item.mSlot] = std::make_shared<
-                    renderengine::ExternalTexture>(item.mGraphicBuffer, mRE,
-                                                   renderengine::ExternalTexture::Usage::READABLE);
+                    renderengine::impl::ExternalTexture>(item.mGraphicBuffer, mRE,
+                                                         renderengine::impl::ExternalTexture::
+                                                                 Usage::READABLE);
         }
     }
 }
diff --git a/services/surfaceflinger/BufferStateLayer.cpp b/services/surfaceflinger/BufferStateLayer.cpp
index 2fac880..6cecd89 100644
--- a/services/surfaceflinger/BufferStateLayer.cpp
+++ b/services/surfaceflinger/BufferStateLayer.cpp
@@ -295,8 +295,8 @@
         return assignTransform(&mDrawingState.transform, t);
     }
 
-    uint32_t bufferWidth = mDrawingState.buffer->getBuffer()->getWidth();
-    uint32_t bufferHeight = mDrawingState.buffer->getBuffer()->getHeight();
+    uint32_t bufferWidth = mDrawingState.buffer->getWidth();
+    uint32_t bufferHeight = mDrawingState.buffer->getHeight();
     // Undo any transformations on the buffer.
     if (mDrawingState.bufferTransform & ui::Transform::ROT_90) {
         std::swap(bufferWidth, bufferHeight);
@@ -368,46 +368,13 @@
     return true;
 }
 
-std::shared_ptr<renderengine::ExternalTexture> BufferStateLayer::getBufferFromBufferData(
-        const BufferData& bufferData) {
-    bool cacheIdChanged = bufferData.flags.test(BufferData::BufferDataChange::cachedBufferChanged);
-    bool bufferSizeExceedsLimit = false;
-    std::shared_ptr<renderengine::ExternalTexture> buffer = nullptr;
-    if (cacheIdChanged && bufferData.buffer != nullptr) {
-        bufferSizeExceedsLimit =
-                mFlinger->exceedsMaxRenderTargetSize(bufferData.buffer->getWidth(),
-                                                     bufferData.buffer->getHeight());
-        if (!bufferSizeExceedsLimit) {
-            ClientCache::getInstance().add(bufferData.cachedBuffer, bufferData.buffer);
-            buffer = ClientCache::getInstance().get(bufferData.cachedBuffer);
-        }
-    } else if (cacheIdChanged) {
-        buffer = ClientCache::getInstance().get(bufferData.cachedBuffer);
-    } else if (bufferData.buffer != nullptr) {
-        bufferSizeExceedsLimit =
-                mFlinger->exceedsMaxRenderTargetSize(bufferData.buffer->getWidth(),
-                                                     bufferData.buffer->getHeight());
-        if (!bufferSizeExceedsLimit) {
-            buffer = std::make_shared<
-                    renderengine::ExternalTexture>(bufferData.buffer, mFlinger->getRenderEngine(),
-                                                   renderengine::ExternalTexture::Usage::READABLE);
-        }
-    }
-    ALOGE_IF(bufferSizeExceedsLimit,
-             "Attempted to create an ExternalTexture for layer %s that exceeds render target size "
-             "limit.",
-             getDebugName());
-    return buffer;
-}
-
-bool BufferStateLayer::setBuffer(const BufferData& bufferData, nsecs_t postTime,
+bool BufferStateLayer::setBuffer(std::shared_ptr<renderengine::ExternalTexture>& buffer,
+                                 const BufferData& bufferData, nsecs_t postTime,
                                  nsecs_t desiredPresentTime, bool isAutoTimestamp,
                                  std::optional<nsecs_t> dequeueTime,
                                  const FrameTimelineInfo& info) {
     ATRACE_CALL();
 
-    const std::shared_ptr<renderengine::ExternalTexture>& buffer =
-            getBufferFromBufferData(bufferData);
     if (!buffer) {
         return false;
     }
@@ -419,8 +386,9 @@
 
     if (mDrawingState.buffer) {
         mReleasePreviousBuffer = true;
-        if (mDrawingState.buffer != mBufferInfo.mBuffer ||
-            mDrawingState.frameNumber != mBufferInfo.mFrameNumber) {
+        if (!mBufferInfo.mBuffer ||
+            (!mDrawingState.buffer->hasSameBuffer(*mBufferInfo.mBuffer) ||
+             mDrawingState.frameNumber != mBufferInfo.mFrameNumber)) {
             // If mDrawingState has a buffer, and we are about to update again
             // before swapping to drawing state, then the first buffer will be
             // dropped and we should decrement the pending buffer count and
@@ -448,7 +416,7 @@
 
     mDrawingState.frameNumber = frameNumber;
     mDrawingState.releaseBufferListener = bufferData.releaseBufferListener;
-    mDrawingState.buffer = buffer;
+    mDrawingState.buffer = std::move(buffer);
     mDrawingState.clientCacheId = bufferData.cachedBuffer;
 
     mDrawingState.acquireFence = bufferData.flags.test(BufferData::BufferDataChange::fenceChanged)
@@ -485,7 +453,7 @@
     setFrameTimelineVsyncForBufferTransaction(info, postTime);
 
     if (buffer && dequeueTime && *dequeueTime != 0) {
-        const uint64_t bufferId = buffer->getBuffer()->getId();
+        const uint64_t bufferId = buffer->getId();
         mFlinger->mFrameTracer->traceNewLayer(layerId, getName().c_str());
         mFlinger->mFrameTracer->traceTimestamp(layerId, bufferId, frameNumber, *dequeueTime,
                                                FrameTracer::FrameEvent::DEQUEUE);
@@ -493,8 +461,8 @@
                                                FrameTracer::FrameEvent::QUEUE);
     }
 
-    mDrawingState.width = mDrawingState.buffer->getBuffer()->getWidth();
-    mDrawingState.height = mDrawingState.buffer->getBuffer()->getHeight();
+    mDrawingState.width = mDrawingState.buffer->getWidth();
+    mDrawingState.height = mDrawingState.buffer->getHeight();
     mDrawingState.releaseBufferEndpoint = bufferData.releaseBufferEndpoint;
     return true;
 }
@@ -599,8 +567,8 @@
         return Rect::INVALID_RECT;
     }
 
-    uint32_t bufWidth = mBufferInfo.mBuffer->getBuffer()->getWidth();
-    uint32_t bufHeight = mBufferInfo.mBuffer->getBuffer()->getHeight();
+    uint32_t bufWidth = mBufferInfo.mBuffer->getWidth();
+    uint32_t bufHeight = mBufferInfo.mBuffer->getHeight();
 
     // Undo any transformations on the buffer and return the result.
     if (mBufferInfo.mTransform & ui::Transform::ROT_90) {
@@ -709,7 +677,7 @@
     }
 
     const int32_t layerId = getSequence();
-    const uint64_t bufferId = mDrawingState.buffer->getBuffer()->getId();
+    const uint64_t bufferId = mDrawingState.buffer->getId();
     const uint64_t frameNumber = mDrawingState.frameNumber;
     const auto acquireFence = std::make_shared<FenceTime>(mDrawingState.acquireFence);
     mFlinger->mTimeStats->setAcquireFence(layerId, frameNumber, acquireFence);
@@ -749,7 +717,7 @@
         return BAD_VALUE;
     }
 
-    if (!mBufferInfo.mBuffer || s.buffer->getBuffer() != mBufferInfo.mBuffer->getBuffer()) {
+    if (!mBufferInfo.mBuffer || !s.buffer->hasSameBuffer(*mBufferInfo.mBuffer)) {
         decrementPendingBufferCount();
     }
 
@@ -874,10 +842,10 @@
 Rect BufferStateLayer::computeBufferCrop(const State& s) {
     if (s.buffer && !s.bufferCrop.isEmpty()) {
         Rect bufferCrop;
-        s.buffer->getBuffer()->getBounds().intersect(s.bufferCrop, &bufferCrop);
+        s.buffer->getBounds().intersect(s.bufferCrop, &bufferCrop);
         return bufferCrop;
     } else if (s.buffer) {
-        return s.buffer->getBuffer()->getBounds();
+        return s.buffer->getBounds();
     } else {
         return s.bufferCrop;
     }
@@ -898,8 +866,8 @@
         return false;
     }
 
-    int32_t bufferWidth = s.buffer->getBuffer()->width;
-    int32_t bufferHeight = s.buffer->getBuffer()->height;
+    int32_t bufferWidth = static_cast<int32_t>(s.buffer->getWidth());
+    int32_t bufferHeight = static_cast<int32_t>(s.buffer->getHeight());
 
     // Undo any transformations on the buffer and return the result.
     if (s.bufferTransform & ui::Transform::ROT_90) {
diff --git a/services/surfaceflinger/BufferStateLayer.h b/services/surfaceflinger/BufferStateLayer.h
index eea700c..2f613d7 100644
--- a/services/surfaceflinger/BufferStateLayer.h
+++ b/services/surfaceflinger/BufferStateLayer.h
@@ -57,7 +57,8 @@
     bool setTransform(uint32_t transform) override;
     bool setTransformToDisplayInverse(bool transformToDisplayInverse) override;
     bool setCrop(const Rect& crop) override;
-    bool setBuffer(const BufferData& bufferData, nsecs_t postTime, nsecs_t desiredPresentTime,
+    bool setBuffer(std::shared_ptr<renderengine::ExternalTexture>& /* buffer */,
+                   const BufferData& bufferData, nsecs_t postTime, nsecs_t desiredPresentTime,
                    bool isAutoTimestamp, std::optional<nsecs_t> dequeueTime,
                    const FrameTimelineInfo& info) override;
     bool setDataspace(ui::Dataspace dataspace) override;
@@ -136,9 +137,6 @@
 
     bool bufferNeedsFiltering() const override;
 
-    std::shared_ptr<renderengine::ExternalTexture> getBufferFromBufferData(
-            const BufferData& bufferData);
-
     ReleaseCallbackId mPreviousReleaseCallbackId = ReleaseCallbackId::INVALID_ID;
     uint64_t mPreviousReleasedFrameNumber = 0;
 
diff --git a/services/surfaceflinger/ClientCache.cpp b/services/surfaceflinger/ClientCache.cpp
index e7b8995..3c7b9d9 100644
--- a/services/surfaceflinger/ClientCache.cpp
+++ b/services/surfaceflinger/ClientCache.cpp
@@ -22,6 +22,7 @@
 #include <cinttypes>
 
 #include <android-base/stringprintf.h>
+#include <renderengine/impl/ExternalTexture.h>
 
 #include "ClientCache.h"
 
@@ -109,8 +110,9 @@
                         "Attempted to build the ClientCache before a RenderEngine instance was "
                         "ready!");
     processBuffers[id].buffer = std::make_shared<
-            renderengine::ExternalTexture>(buffer, *mRenderEngine,
-                                           renderengine::ExternalTexture::Usage::READABLE);
+            renderengine::impl::ExternalTexture>(buffer, *mRenderEngine,
+                                                 renderengine::impl::ExternalTexture::Usage::
+                                                         READABLE);
     return true;
 }
 
diff --git a/services/surfaceflinger/CompositionEngine/src/RenderSurface.cpp b/services/surfaceflinger/CompositionEngine/src/RenderSurface.cpp
index a19d23f..12c2c8e 100644
--- a/services/surfaceflinger/CompositionEngine/src/RenderSurface.cpp
+++ b/services/surfaceflinger/CompositionEngine/src/RenderSurface.cpp
@@ -28,6 +28,7 @@
 #include <log/log.h>
 #include <renderengine/ExternalTexture.h>
 #include <renderengine/RenderEngine.h>
+#include <renderengine/impl/ExternalTexture.h>
 #include <system/window.h>
 #include <ui/GraphicBuffer.h>
 #include <ui/Rect.h>
@@ -182,9 +183,10 @@
         mTexture = texture;
     } else {
         mTexture = std::make_shared<
-                renderengine::ExternalTexture>(GraphicBuffer::from(buffer),
-                                               mCompositionEngine.getRenderEngine(),
-                                               renderengine::ExternalTexture::Usage::WRITEABLE);
+                renderengine::impl::ExternalTexture>(GraphicBuffer::from(buffer),
+                                                     mCompositionEngine.getRenderEngine(),
+                                                     renderengine::impl::ExternalTexture::Usage::
+                                                             WRITEABLE);
     }
     mTextureCache.push_back(mTexture);
     if (mTextureCache.size() > mMaxTextureCacheSize) {
diff --git a/services/surfaceflinger/CompositionEngine/src/planner/TexturePool.cpp b/services/surfaceflinger/CompositionEngine/src/planner/TexturePool.cpp
index 497c433..54ecb56 100644
--- a/services/surfaceflinger/CompositionEngine/src/planner/TexturePool.cpp
+++ b/services/surfaceflinger/CompositionEngine/src/planner/TexturePool.cpp
@@ -20,6 +20,7 @@
 #define LOG_TAG "Planner"
 
 #include <compositionengine/impl/planner/TexturePool.h>
+#include <renderengine/impl/ExternalTexture.h>
 #include <utils/Log.h>
 
 namespace android::compositionengine::impl::planner {
@@ -82,16 +83,19 @@
 std::shared_ptr<renderengine::ExternalTexture> TexturePool::genTexture() {
     LOG_ALWAYS_FATAL_IF(!mSize.isValid(), "Attempted to generate texture with invalid size");
     return std::make_shared<
-            renderengine::ExternalTexture>(sp<GraphicBuffer>::
-                                                   make(mSize.getWidth(), mSize.getHeight(),
-                                                        HAL_PIXEL_FORMAT_RGBA_8888, 1,
-                                                        GraphicBuffer::USAGE_HW_RENDER |
-                                                                GraphicBuffer::USAGE_HW_COMPOSER |
-                                                                GraphicBuffer::USAGE_HW_TEXTURE,
-                                                        "Planner"),
-                                           mRenderEngine,
-                                           renderengine::ExternalTexture::Usage::READABLE |
-                                                   renderengine::ExternalTexture::Usage::WRITEABLE);
+            renderengine::impl::
+                    ExternalTexture>(sp<GraphicBuffer>::
+                                             make(static_cast<uint32_t>(mSize.getWidth()),
+                                                  static_cast<uint32_t>(mSize.getHeight()),
+                                                  HAL_PIXEL_FORMAT_RGBA_8888, 1U,
+                                                  static_cast<uint64_t>(
+                                                          GraphicBuffer::USAGE_HW_RENDER |
+                                                          GraphicBuffer::USAGE_HW_COMPOSER |
+                                                          GraphicBuffer::USAGE_HW_TEXTURE),
+                                                  "Planner"),
+                                     mRenderEngine,
+                                     renderengine::impl::ExternalTexture::Usage::READABLE |
+                                             renderengine::impl::ExternalTexture::Usage::WRITEABLE);
 }
 
 void TexturePool::setEnabled(bool enabled) {
diff --git a/services/surfaceflinger/CompositionEngine/tests/OutputLayerTest.cpp b/services/surfaceflinger/CompositionEngine/tests/OutputLayerTest.cpp
index ad7976f..37f17f5 100644
--- a/services/surfaceflinger/CompositionEngine/tests/OutputLayerTest.cpp
+++ b/services/surfaceflinger/CompositionEngine/tests/OutputLayerTest.cpp
@@ -24,6 +24,7 @@
 #include <gtest/gtest.h>
 #include <log/log.h>
 
+#include <renderengine/impl/ExternalTexture.h>
 #include <renderengine/mock/RenderEngine.h>
 #include <ui/PixelFormat.h>
 #include "MockHWC2.h"
@@ -815,10 +816,11 @@
         auto& overrideInfo = mOutputLayer.editState().overrideInfo;
 
         overrideInfo.buffer = std::make_shared<
-                renderengine::ExternalTexture>(kOverrideBuffer, mRenderEngine,
-                                               renderengine::ExternalTexture::Usage::READABLE |
-                                                       renderengine::ExternalTexture::Usage::
-                                                               WRITEABLE);
+                renderengine::impl::ExternalTexture>(kOverrideBuffer, mRenderEngine,
+                                                     renderengine::impl::ExternalTexture::Usage::
+                                                                     READABLE |
+                                                             renderengine::impl::ExternalTexture::
+                                                                     Usage::WRITEABLE);
         overrideInfo.acquireFence = kOverrideFence;
         overrideInfo.displayFrame = kOverrideDisplayFrame;
         overrideInfo.dataspace = kOverrideDataspace;
diff --git a/services/surfaceflinger/CompositionEngine/tests/OutputTest.cpp b/services/surfaceflinger/CompositionEngine/tests/OutputTest.cpp
index 6d96260..5fcb52d 100644
--- a/services/surfaceflinger/CompositionEngine/tests/OutputTest.cpp
+++ b/services/surfaceflinger/CompositionEngine/tests/OutputTest.cpp
@@ -26,6 +26,8 @@
 #include <compositionengine/mock/RenderSurface.h>
 #include <ftl/future.h>
 #include <gtest/gtest.h>
+#include <renderengine/ExternalTexture.h>
+#include <renderengine/impl/ExternalTexture.h>
 #include <renderengine/mock/RenderEngine.h>
 #include <ui/Rect.h>
 #include <ui/Region.h>
@@ -37,7 +39,6 @@
 #include "MockHWC2.h"
 #include "RegionMatcher.h"
 #include "TestUtils.h"
-#include "renderengine/ExternalTexture.h"
 
 namespace android::compositionengine {
 namespace {
@@ -273,9 +274,10 @@
     // Inject some layers
     InjectedLayer layer;
     layer.outputLayerState.overrideInfo.buffer = std::make_shared<
-            renderengine::ExternalTexture>(new GraphicBuffer(), renderEngine,
-                                           renderengine::ExternalTexture::Usage::READABLE |
-                                                   renderengine::ExternalTexture::Usage::WRITEABLE);
+            renderengine::impl::
+                    ExternalTexture>(new GraphicBuffer(), renderEngine,
+                                     renderengine::impl::ExternalTexture::Usage::READABLE |
+                                             renderengine::impl::ExternalTexture::Usage::WRITEABLE);
     injectOutputLayer(layer);
     // inject a null layer to check for null exceptions
     injectNullOutputLayer();
@@ -956,9 +958,10 @@
     mOutput->planComposition();
 
     std::shared_ptr<renderengine::ExternalTexture> buffer = std::make_shared<
-            renderengine::ExternalTexture>(new GraphicBuffer(), renderEngine,
-                                           renderengine::ExternalTexture::Usage::READABLE |
-                                                   renderengine::ExternalTexture::Usage::WRITEABLE);
+            renderengine::impl::
+                    ExternalTexture>(new GraphicBuffer(), renderEngine,
+                                     renderengine::impl::ExternalTexture::Usage::READABLE |
+                                             renderengine::impl::ExternalTexture::Usage::WRITEABLE);
     layer1.outputLayerState.overrideInfo.buffer = buffer;
     layer2.outputLayerState.overrideInfo.buffer = buffer;
     layer1.outputLayerState.overrideInfo.peekThroughLayer = layer3.outputLayer;
@@ -3077,9 +3080,10 @@
     mock::RenderSurface* mRenderSurface = new StrictMock<mock::RenderSurface>();
     StrictMock<OutputPartialMock> mOutput;
     std::shared_ptr<renderengine::ExternalTexture> mOutputBuffer = std::make_shared<
-            renderengine::ExternalTexture>(new GraphicBuffer(), mRenderEngine,
-                                           renderengine::ExternalTexture::Usage::READABLE |
-                                                   renderengine::ExternalTexture::Usage::WRITEABLE);
+            renderengine::impl::
+                    ExternalTexture>(new GraphicBuffer(), mRenderEngine,
+                                     renderengine::impl::ExternalTexture::Usage::READABLE |
+                                             renderengine::impl::ExternalTexture::Usage::WRITEABLE);
 
     std::optional<base::unique_fd> mReadyFence;
 };
@@ -3313,9 +3317,10 @@
             .WillRepeatedly(Return());
 
     const auto otherOutputBuffer = std::make_shared<
-            renderengine::ExternalTexture>(new GraphicBuffer(), mRenderEngine,
-                                           renderengine::ExternalTexture::Usage::READABLE |
-                                                   renderengine::ExternalTexture::Usage::WRITEABLE);
+            renderengine::impl::
+                    ExternalTexture>(new GraphicBuffer(), mRenderEngine,
+                                     renderengine::impl::ExternalTexture::Usage::READABLE |
+                                             renderengine::impl::ExternalTexture::Usage::WRITEABLE);
     EXPECT_CALL(*mRenderSurface, dequeueBuffer(_))
             .WillOnce(Return(mOutputBuffer))
             .WillOnce(Return(otherOutputBuffer));
diff --git a/services/surfaceflinger/CompositionEngine/tests/RenderSurfaceTest.cpp b/services/surfaceflinger/CompositionEngine/tests/RenderSurfaceTest.cpp
index 7c8e41b..e5f9ebf 100644
--- a/services/surfaceflinger/CompositionEngine/tests/RenderSurfaceTest.cpp
+++ b/services/surfaceflinger/CompositionEngine/tests/RenderSurfaceTest.cpp
@@ -27,6 +27,7 @@
 #include <compositionengine/mock/OutputLayer.h>
 #include <gtest/gtest.h>
 #include <renderengine/ExternalTexture.h>
+#include <renderengine/impl/ExternalTexture.h>
 #include <renderengine/mock/RenderEngine.h>
 #include <ui/GraphicBuffer.h>
 
@@ -251,9 +252,10 @@
 
 TEST_F(RenderSurfaceTest, queueBufferHandlesNoClientComposition) {
     const auto buffer = std::make_shared<
-            renderengine::ExternalTexture>(new GraphicBuffer(), mRenderEngine,
-                                           renderengine::ExternalTexture::Usage::READABLE |
-                                                   renderengine::ExternalTexture::Usage::WRITEABLE);
+            renderengine::impl::
+                    ExternalTexture>(new GraphicBuffer(), mRenderEngine,
+                                     renderengine::impl::ExternalTexture::Usage::READABLE |
+                                             renderengine::impl::ExternalTexture::Usage::WRITEABLE);
     mSurface.mutableTextureForTest() = buffer;
 
     impl::OutputCompositionState state;
@@ -269,8 +271,8 @@
 }
 
 TEST_F(RenderSurfaceTest, queueBufferHandlesClientComposition) {
-    const auto buffer = std::make_shared<renderengine::ExternalTexture>(new GraphicBuffer(),
-                                                                        mRenderEngine, false);
+    const auto buffer = std::make_shared<renderengine::impl::ExternalTexture>(new GraphicBuffer(),
+                                                                              mRenderEngine, false);
     mSurface.mutableTextureForTest() = buffer;
 
     impl::OutputCompositionState state;
@@ -288,8 +290,8 @@
 }
 
 TEST_F(RenderSurfaceTest, queueBufferHandlesFlipClientTargetRequest) {
-    const auto buffer = std::make_shared<renderengine::ExternalTexture>(new GraphicBuffer(),
-                                                                        mRenderEngine, false);
+    const auto buffer = std::make_shared<renderengine::impl::ExternalTexture>(new GraphicBuffer(),
+                                                                              mRenderEngine, false);
     mSurface.mutableTextureForTest() = buffer;
 
     impl::OutputCompositionState state;
@@ -327,8 +329,8 @@
 }
 
 TEST_F(RenderSurfaceTest, queueBufferHandlesNativeWindowQueueBufferFailureOnVirtualDisplay) {
-    const auto buffer = std::make_shared<renderengine::ExternalTexture>(new GraphicBuffer(),
-                                                                        mRenderEngine, false);
+    const auto buffer = std::make_shared<renderengine::impl::ExternalTexture>(new GraphicBuffer(),
+                                                                              mRenderEngine, false);
     mSurface.mutableTextureForTest() = buffer;
 
     impl::OutputCompositionState state;
diff --git a/services/surfaceflinger/CompositionEngine/tests/planner/CachedSetTest.cpp b/services/surfaceflinger/CompositionEngine/tests/planner/CachedSetTest.cpp
index d5a117a..4ae921d 100644
--- a/services/surfaceflinger/CompositionEngine/tests/planner/CachedSetTest.cpp
+++ b/services/surfaceflinger/CompositionEngine/tests/planner/CachedSetTest.cpp
@@ -22,6 +22,7 @@
 #include <gmock/gmock-actions.h>
 #include <gtest/gtest.h>
 #include <renderengine/ExternalTexture.h>
+#include <renderengine/mock/FakeExternalTexture.h>
 #include <renderengine/mock/RenderEngine.h>
 #include <ui/GraphicTypes.h>
 #include <utils/Errors.h>
@@ -702,9 +703,11 @@
     std::vector<compositionengine::LayerFE::LayerSettings> clientCompList3;
     clientCompList3.push_back({});
 
-    clientCompList3[0].source.buffer.buffer = std::make_shared<
-            renderengine::ExternalTexture>(sp<GraphicBuffer>::make(), mRenderEngine,
-                                           renderengine::ExternalTexture::READABLE);
+    clientCompList3[0].source.buffer.buffer =
+            std::make_shared<renderengine::mock::FakeExternalTexture>(1U /*width*/, 1U /*height*/,
+                                                                      1ULL /* bufferId */,
+                                                                      HAL_PIXEL_FORMAT_RGBA_8888,
+                                                                      0ULL /*usage*/);
 
     EXPECT_CALL(*layerFE1, prepareClientCompositionList(_)).WillOnce(Return(clientCompList1));
     EXPECT_CALL(*layerFE2, prepareClientCompositionList(_)).WillOnce(Return(clientCompList2));
@@ -901,9 +904,11 @@
     std::vector<compositionengine::LayerFE::LayerSettings> clientCompList3;
     clientCompList3.push_back({});
 
-    clientCompList3[0].source.buffer.buffer = std::make_shared<
-            renderengine::ExternalTexture>(sp<GraphicBuffer>::make(), mRenderEngine,
-                                           renderengine::ExternalTexture::READABLE);
+    clientCompList3[0].source.buffer.buffer =
+            std::make_shared<renderengine::mock::FakeExternalTexture>(1U /*width*/, 1U /*height*/,
+                                                                      1ULL /* bufferId */,
+                                                                      HAL_PIXEL_FORMAT_RGBA_8888,
+                                                                      0ULL /*usage*/);
 
     EXPECT_CALL(*layerFE1,
                 prepareClientCompositionList(ClientCompositionTargetSettingsBlurSettingsEq(
diff --git a/services/surfaceflinger/CompositionEngine/tests/planner/FlattenerTest.cpp b/services/surfaceflinger/CompositionEngine/tests/planner/FlattenerTest.cpp
index 35d051e..58dc244 100644
--- a/services/surfaceflinger/CompositionEngine/tests/planner/FlattenerTest.cpp
+++ b/services/surfaceflinger/CompositionEngine/tests/planner/FlattenerTest.cpp
@@ -23,6 +23,7 @@
 #include <gtest/gtest.h>
 #include <renderengine/ExternalTexture.h>
 #include <renderengine/LayerSettings.h>
+#include <renderengine/impl/ExternalTexture.h>
 #include <renderengine/mock/RenderEngine.h>
 #include <chrono>
 
@@ -639,9 +640,10 @@
             LayerFE::LayerSettings{},
     };
     clientCompositionList[0].source.buffer.buffer = std::make_shared<
-            renderengine::ExternalTexture>(mTestLayers[2]->layerFECompositionState.buffer,
-                                           mRenderEngine,
-                                           renderengine::ExternalTexture::Usage::READABLE);
+            renderengine::impl::ExternalTexture>(mTestLayers[2]->layerFECompositionState.buffer,
+                                                 mRenderEngine,
+                                                 renderengine::impl::ExternalTexture::Usage::
+                                                         READABLE);
     EXPECT_CALL(*mTestLayers[2]->layerFE, prepareClientCompositionList(_))
             .WillOnce(Return(clientCompositionList));
 
@@ -711,9 +713,10 @@
             LayerFE::LayerSettings{},
     };
     clientCompositionList[0].source.buffer.buffer = std::make_shared<
-            renderengine::ExternalTexture>(mTestLayers[1]->layerFECompositionState.buffer,
-                                           mRenderEngine,
-                                           renderengine::ExternalTexture::Usage::READABLE);
+            renderengine::impl::ExternalTexture>(mTestLayers[1]->layerFECompositionState.buffer,
+                                                 mRenderEngine,
+                                                 renderengine::impl::ExternalTexture::Usage::
+                                                         READABLE);
     EXPECT_CALL(*mTestLayers[1]->layerFE, prepareClientCompositionList(_))
             .WillOnce(Return(clientCompositionList));
 
@@ -781,9 +784,10 @@
             LayerFE::LayerSettings{},
     };
     clientCompositionList[0].source.buffer.buffer = std::make_shared<
-            renderengine::ExternalTexture>(mTestLayers[1]->layerFECompositionState.buffer,
-                                           mRenderEngine,
-                                           renderengine::ExternalTexture::Usage::READABLE);
+            renderengine::impl::ExternalTexture>(mTestLayers[1]->layerFECompositionState.buffer,
+                                                 mRenderEngine,
+                                                 renderengine::impl::ExternalTexture::Usage::
+                                                         READABLE);
     EXPECT_CALL(*mTestLayers[1]->layerFE, prepareClientCompositionList(_))
             .WillOnce(Return(clientCompositionList));
 
diff --git a/services/surfaceflinger/Layer.h b/services/surfaceflinger/Layer.h
index 31cdf0b..0d2618a 100644
--- a/services/surfaceflinger/Layer.h
+++ b/services/surfaceflinger/Layer.h
@@ -416,8 +416,10 @@
     // Used only to set BufferStateLayer state
     virtual bool setTransform(uint32_t /*transform*/) { return false; };
     virtual bool setTransformToDisplayInverse(bool /*transformToDisplayInverse*/) { return false; };
-    virtual bool setBuffer(const BufferData&, nsecs_t /*postTime*/, nsecs_t /*desiredPresentTime*/,
-                           bool /*isAutoTimestamp*/, std::optional<nsecs_t> /* dequeueTime */,
+    virtual bool setBuffer(std::shared_ptr<renderengine::ExternalTexture>& /* buffer */,
+                           const BufferData& /* bufferData */, nsecs_t /* postTime */,
+                           nsecs_t /*desiredPresentTime*/, bool /*isAutoTimestamp*/,
+                           std::optional<nsecs_t> /* dequeueTime */,
                            const FrameTimelineInfo& /*info*/) {
         return false;
     };
diff --git a/services/surfaceflinger/RegionSamplingThread.cpp b/services/surfaceflinger/RegionSamplingThread.cpp
index da8c3e0..ff30348 100644
--- a/services/surfaceflinger/RegionSamplingThread.cpp
+++ b/services/surfaceflinger/RegionSamplingThread.cpp
@@ -31,6 +31,7 @@
 #include <cutils/properties.h>
 #include <ftl/future.h>
 #include <gui/SyncScreenCaptureListener.h>
+#include <renderengine/impl/ExternalTexture.h>
 #include <ui/DisplayStatInfo.h>
 #include <utils/Trace.h>
 
@@ -351,8 +352,9 @@
         LOG_ALWAYS_FATAL_IF(bufferStatus != OK, "captureSample: Buffer failed to allocate: %d",
                             bufferStatus);
         buffer = std::make_shared<
-                renderengine::ExternalTexture>(graphicBuffer, mFlinger.getRenderEngine(),
-                                               renderengine::ExternalTexture::Usage::WRITEABLE);
+                renderengine::impl::ExternalTexture>(graphicBuffer, mFlinger.getRenderEngine(),
+                                                     renderengine::impl::ExternalTexture::Usage::
+                                                             WRITEABLE);
     }
 
     auto captureScreenResultFuture =
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index bd13c41..1dc75c8 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -65,6 +65,7 @@
 #include <private/gui/SyncFeatures.h>
 #include <processgroup/processgroup.h>
 #include <renderengine/RenderEngine.h>
+#include <renderengine/impl/ExternalTexture.h>
 #include <sys/types.h>
 #include <ui/ColorSpace.h>
 #include <ui/DataspaceUtils.h>
@@ -4419,10 +4420,13 @@
         }
     }
 
-    if (what & layer_state_t::eBufferChanged &&
-        layer->setBuffer(*s.bufferData, postTime, desiredPresentTime, isAutoTimestamp,
-                         dequeueBufferTimestamp, frameTimelineInfo)) {
-        flags |= eTraversalNeeded;
+    if (what & layer_state_t::eBufferChanged) {
+        std::shared_ptr<renderengine::ExternalTexture> buffer =
+                getExternalTextureFromBufferData(*s.bufferData, layer->getDebugName());
+        if (layer->setBuffer(buffer, *s.bufferData, postTime, desiredPresentTime, isAutoTimestamp,
+                             dequeueBufferTimestamp, frameTimelineInfo)) {
+            flags |= eTraversalNeeded;
+        }
     } else if (frameTimelineInfo.vsyncId != FrameTimelineInfo::INVALID_VSYNC_ID) {
         layer->setFrameTimelineVsyncForBufferlessTransaction(frameTimelineInfo, postTime);
     }
@@ -6384,9 +6388,10 @@
     const status_t bufferStatus = buffer->initCheck();
     LOG_ALWAYS_FATAL_IF(bufferStatus != OK, "captureScreenCommon: Buffer failed to allocate: %d",
                         bufferStatus);
-    const auto texture = std::make_shared<
-            renderengine::ExternalTexture>(buffer, getRenderEngine(),
-                                           renderengine::ExternalTexture::Usage::WRITEABLE);
+    const std::shared_ptr<renderengine::ExternalTexture> texture = std::make_shared<
+            renderengine::impl::ExternalTexture>(buffer, getRenderEngine(),
+                                                 renderengine::impl::ExternalTexture::Usage::
+                                                         WRITEABLE);
     return captureScreenCommon(std::move(renderAreaFuture), traverseLayers, texture,
                                false /* regionSampling */, grayscale, captureListener);
 }
@@ -6463,7 +6468,7 @@
                 captureResults.capturedSecureLayers || (layer->isVisible() && layer->isSecure());
     });
 
-    const bool useProtected = buffer->getBuffer()->getUsage() & GRALLOC_USAGE_PROTECTED;
+    const bool useProtected = buffer->getUsage() & GRALLOC_USAGE_PROTECTED;
 
     // We allow the system server to take screenshots of secure layers for
     // use in situations like the Screen-rotation animation and place
@@ -7074,6 +7079,36 @@
     return NO_ERROR;
 }
 
+std::shared_ptr<renderengine::ExternalTexture> SurfaceFlinger::getExternalTextureFromBufferData(
+        const BufferData& bufferData, const char* layerName) const {
+    bool cacheIdChanged = bufferData.flags.test(BufferData::BufferDataChange::cachedBufferChanged);
+    bool bufferSizeExceedsLimit = false;
+    std::shared_ptr<renderengine::ExternalTexture> buffer = nullptr;
+    if (cacheIdChanged && bufferData.buffer != nullptr) {
+        bufferSizeExceedsLimit = exceedsMaxRenderTargetSize(bufferData.buffer->getWidth(),
+                                                            bufferData.buffer->getHeight());
+        if (!bufferSizeExceedsLimit) {
+            ClientCache::getInstance().add(bufferData.cachedBuffer, bufferData.buffer);
+            buffer = ClientCache::getInstance().get(bufferData.cachedBuffer);
+        }
+    } else if (cacheIdChanged) {
+        buffer = ClientCache::getInstance().get(bufferData.cachedBuffer);
+    } else if (bufferData.buffer != nullptr) {
+        bufferSizeExceedsLimit = exceedsMaxRenderTargetSize(bufferData.buffer->getWidth(),
+                                                            bufferData.buffer->getHeight());
+        if (!bufferSizeExceedsLimit) {
+            buffer = std::make_shared<
+                    renderengine::impl::ExternalTexture>(bufferData.buffer, getRenderEngine(),
+                                                         renderengine::impl::ExternalTexture::
+                                                                 Usage::READABLE);
+        }
+    }
+    ALOGE_IF(bufferSizeExceedsLimit,
+             "Attempted to create an ExternalTexture for layer %s that exceeds render target size "
+             "limit.",
+             layerName);
+    return buffer;
+}
 } // namespace android
 
 #if defined(__gl_h_)
diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index 0c4236f..338b357 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -330,6 +330,9 @@
     virtual void processDisplayAdded(const wp<IBinder>& displayToken, const DisplayDeviceState&)
             REQUIRES(mStateLock);
 
+    virtual std::shared_ptr<renderengine::ExternalTexture> getExternalTextureFromBufferData(
+            const BufferData& bufferData, const char* layerName) const;
+
     // Returns true if any display matches a `bool(const DisplayDevice&)` predicate.
     template <typename Predicate>
     bool hasDisplay(Predicate p) const REQUIRES(mStateLock) {
diff --git a/services/surfaceflinger/tests/unittests/CompositionTest.cpp b/services/surfaceflinger/tests/unittests/CompositionTest.cpp
index f1e9b31..427159f 100644
--- a/services/surfaceflinger/tests/unittests/CompositionTest.cpp
+++ b/services/surfaceflinger/tests/unittests/CompositionTest.cpp
@@ -30,6 +30,7 @@
 #include <gui/IProducerListener.h>
 #include <gui/LayerMetadata.h>
 #include <log/log.h>
+#include <renderengine/mock/FakeExternalTexture.h>
 #include <renderengine/mock/Framebuffer.h>
 #include <renderengine/mock/Image.h>
 #include <renderengine/mock/RenderEngine.h>
@@ -234,15 +235,13 @@
                                                    CaptureArgs::UNSET_UID, visitor);
     };
 
-    // TODO: Eliminate expensive/real allocation if possible.
     const uint32_t usage = GRALLOC_USAGE_SW_READ_OFTEN | GRALLOC_USAGE_SW_WRITE_OFTEN |
             GRALLOC_USAGE_HW_RENDER | GRALLOC_USAGE_HW_TEXTURE;
-    mCaptureScreenBuffer = std::make_shared<
-            renderengine::ExternalTexture>(new GraphicBuffer(renderArea->getReqWidth(),
-                                                             renderArea->getReqHeight(),
-                                                             HAL_PIXEL_FORMAT_RGBA_8888, 1, usage,
-                                                             "screenshot"),
-                                           *mRenderEngine, true);
+    mCaptureScreenBuffer =
+            std::make_shared<renderengine::mock::FakeExternalTexture>(renderArea->getReqWidth(),
+                                                                      renderArea->getReqHeight(),
+                                                                      HAL_PIXEL_FORMAT_RGBA_8888, 1,
+                                                                      usage);
 
     auto result = mFlinger.renderScreenImplLocked(*renderArea, traverseLayers, mCaptureScreenBuffer,
                                                   forSystem, regionSampling);
diff --git a/services/surfaceflinger/tests/unittests/TransactionFrameTracerTest.cpp b/services/surfaceflinger/tests/unittests/TransactionFrameTracerTest.cpp
index deeb785..5364630 100644
--- a/services/surfaceflinger/tests/unittests/TransactionFrameTracerTest.cpp
+++ b/services/surfaceflinger/tests/unittests/TransactionFrameTracerTest.cpp
@@ -22,6 +22,7 @@
 #include <gui/SurfaceComposerClient.h>
 #include <log/log.h>
 #include <renderengine/ExternalTexture.h>
+#include <renderengine/mock/FakeExternalTexture.h>
 #include <renderengine/mock/RenderEngine.h>
 #include <utils/String8.h>
 
@@ -101,9 +102,8 @@
         sp<BufferStateLayer> layer = createBufferStateLayer();
 
         sp<Fence> fence(new Fence());
-        const auto buffer = new GraphicBuffer(1, 1, HAL_PIXEL_FORMAT_RGBA_8888, 1, 0);
         int32_t layerId = layer->getSequence();
-        uint64_t bufferId = buffer->getId();
+        uint64_t bufferId = 42;
         uint64_t frameNumber = 5;
         nsecs_t dequeueTime = 10;
         nsecs_t postTime = 20;
@@ -115,13 +115,16 @@
                     traceTimestamp(layerId, bufferId, frameNumber, postTime,
                                    FrameTracer::FrameEvent::QUEUE, /*duration*/ 0));
         BufferData bufferData;
-        bufferData.buffer = buffer;
         bufferData.acquireFence = fence;
         bufferData.frameNumber = frameNumber;
         bufferData.flags |= BufferData::BufferDataChange::fenceChanged;
         bufferData.flags |= BufferData::BufferDataChange::frameNumberChanged;
-        layer->setBuffer(bufferData, postTime, /*desiredPresentTime*/ 30, false, dequeueTime,
-                         FrameTimelineInfo{});
+        std::shared_ptr<renderengine::ExternalTexture> externalTexture = std::make_shared<
+                renderengine::mock::FakeExternalTexture>(1U /*width*/, 1U /*height*/, bufferId,
+                                                         HAL_PIXEL_FORMAT_RGBA_8888,
+                                                         0ULL /*usage*/);
+        layer->setBuffer(externalTexture, bufferData, postTime, /*desiredPresentTime*/ 30, false,
+                         dequeueTime, FrameTimelineInfo{});
 
         commitTransaction(layer.get());
         bool computeVisisbleRegions;
diff --git a/services/surfaceflinger/tests/unittests/TransactionSurfaceFrameTest.cpp b/services/surfaceflinger/tests/unittests/TransactionSurfaceFrameTest.cpp
index 704340d..5bb4c92 100644
--- a/services/surfaceflinger/tests/unittests/TransactionSurfaceFrameTest.cpp
+++ b/services/surfaceflinger/tests/unittests/TransactionSurfaceFrameTest.cpp
@@ -22,6 +22,7 @@
 #include <gui/SurfaceComposerClient.h>
 #include <log/log.h>
 #include <renderengine/ExternalTexture.h>
+#include <renderengine/mock/FakeExternalTexture.h>
 #include <renderengine/mock/RenderEngine.h>
 #include <utils/String8.h>
 
@@ -114,14 +115,17 @@
         sp<BufferStateLayer> layer = createBufferStateLayer();
         sp<Fence> fence(new Fence());
         auto acquireFence = fenceFactory.createFenceTimeForTest(fence);
-        const auto buffer = new GraphicBuffer(1, 1, HAL_PIXEL_FORMAT_RGBA_8888, 1, 0);
         BufferData bufferData;
-        bufferData.buffer = buffer;
         bufferData.acquireFence = fence;
         bufferData.frameNumber = 1;
         bufferData.flags |= BufferData::BufferDataChange::fenceChanged;
         bufferData.flags |= BufferData::BufferDataChange::frameNumberChanged;
-        layer->setBuffer(bufferData, 10, 20, false, std::nullopt,
+        std::shared_ptr<renderengine::ExternalTexture> externalTexture = std::make_shared<
+                renderengine::mock::FakeExternalTexture>(1U /*width*/, 1U /*height*/,
+                                                         1ULL /* bufferId */,
+                                                         HAL_PIXEL_FORMAT_RGBA_8888,
+                                                         0ULL /*usage*/);
+        layer->setBuffer(externalTexture, bufferData, 10, 20, false, std::nullopt,
                          {/*vsyncId*/ 1, /*inputEventId*/ 0});
         acquireFence->signalForTest(12);
 
@@ -145,14 +149,17 @@
 
         sp<Fence> fence1(new Fence());
         auto acquireFence1 = fenceFactory.createFenceTimeForTest(fence1);
-        const auto buffer1 = new GraphicBuffer(1, 1, HAL_PIXEL_FORMAT_RGBA_8888, 1, 0);
         BufferData bufferData;
-        bufferData.buffer = buffer1;
         bufferData.acquireFence = fence1;
         bufferData.frameNumber = 1;
         bufferData.flags |= BufferData::BufferDataChange::fenceChanged;
         bufferData.flags |= BufferData::BufferDataChange::frameNumberChanged;
-        layer->setBuffer(bufferData, 10, 20, false, std::nullopt,
+        std::shared_ptr<renderengine::ExternalTexture> externalTexture1 = std::make_shared<
+                renderengine::mock::FakeExternalTexture>(1U /*width*/, 1U /*height*/,
+                                                         1ULL /* bufferId */,
+                                                         HAL_PIXEL_FORMAT_RGBA_8888,
+                                                         0ULL /*usage*/);
+        layer->setBuffer(externalTexture1, bufferData, 10, 20, false, std::nullopt,
                          {/*vsyncId*/ 1, /*inputEventId*/ 0});
         EXPECT_EQ(0u, layer->mDrawingState.bufferlessSurfaceFramesTX.size());
         ASSERT_NE(nullptr, layer->mDrawingState.bufferSurfaceFrameTX);
@@ -160,14 +167,17 @@
 
         sp<Fence> fence2(new Fence());
         auto acquireFence2 = fenceFactory.createFenceTimeForTest(fence2);
-        const auto buffer2 = new GraphicBuffer(1, 1, HAL_PIXEL_FORMAT_RGBA_8888, 1, 0);
         nsecs_t start = systemTime();
-        bufferData.buffer = buffer2;
         bufferData.acquireFence = fence2;
         bufferData.frameNumber = 1;
         bufferData.flags |= BufferData::BufferDataChange::fenceChanged;
         bufferData.flags |= BufferData::BufferDataChange::frameNumberChanged;
-        layer->setBuffer(bufferData, 10, 20, false, std::nullopt,
+        std::shared_ptr<renderengine::ExternalTexture> externalTexture2 = std::make_shared<
+                renderengine::mock::FakeExternalTexture>(1U /*width*/, 1U /*height*/,
+                                                         2ULL /* bufferId */,
+                                                         HAL_PIXEL_FORMAT_RGBA_8888,
+                                                         0ULL /*usage*/);
+        layer->setBuffer(externalTexture2, bufferData, 10, 20, false, std::nullopt,
                          {/*vsyncId*/ 1, /*inputEventId*/ 0});
         nsecs_t end = systemTime();
         acquireFence2->signalForTest(12);
@@ -203,14 +213,17 @@
 
         sp<Fence> fence(new Fence());
         auto acquireFence = fenceFactory.createFenceTimeForTest(fence);
-        const auto buffer = new GraphicBuffer(1, 1, HAL_PIXEL_FORMAT_RGBA_8888, 1, 0);
         BufferData bufferData;
-        bufferData.buffer = buffer;
         bufferData.acquireFence = fence;
         bufferData.frameNumber = 1;
         bufferData.flags |= BufferData::BufferDataChange::fenceChanged;
         bufferData.flags |= BufferData::BufferDataChange::frameNumberChanged;
-        layer->setBuffer(bufferData, 10, 20, false, std::nullopt,
+        std::shared_ptr<renderengine::ExternalTexture> externalTexture = std::make_shared<
+                renderengine::mock::FakeExternalTexture>(1U /*width*/, 1U /*height*/,
+                                                         1ULL /* bufferId */,
+                                                         HAL_PIXEL_FORMAT_RGBA_8888,
+                                                         0ULL /*usage*/);
+        layer->setBuffer(externalTexture, bufferData, 10, 20, false, std::nullopt,
                          {/*vsyncId*/ 1, /*inputEventId*/ 0});
         acquireFence->signalForTest(12);
 
@@ -234,14 +247,17 @@
         sp<BufferStateLayer> layer = createBufferStateLayer();
         sp<Fence> fence(new Fence());
         auto acquireFence = fenceFactory.createFenceTimeForTest(fence);
-        const auto buffer = new GraphicBuffer(1, 1, HAL_PIXEL_FORMAT_RGBA_8888, 1, 0);
         BufferData bufferData;
-        bufferData.buffer = buffer;
         bufferData.acquireFence = fence;
         bufferData.frameNumber = 1;
         bufferData.flags |= BufferData::BufferDataChange::fenceChanged;
         bufferData.flags |= BufferData::BufferDataChange::frameNumberChanged;
-        layer->setBuffer(bufferData, 10, 20, false, std::nullopt,
+        std::shared_ptr<renderengine::ExternalTexture> externalTexture = std::make_shared<
+                renderengine::mock::FakeExternalTexture>(1U /*width*/, 1U /*height*/,
+                                                         1ULL /* bufferId */,
+                                                         HAL_PIXEL_FORMAT_RGBA_8888,
+                                                         0ULL /*usage*/);
+        layer->setBuffer(externalTexture, bufferData, 10, 20, false, std::nullopt,
                          {/*vsyncId*/ 1, /*inputEventId*/ 0});
         EXPECT_EQ(0u, layer->mDrawingState.bufferlessSurfaceFramesTX.size());
         ASSERT_NE(nullptr, layer->mDrawingState.bufferSurfaceFrameTX);
@@ -269,14 +285,17 @@
 
         sp<Fence> fence(new Fence());
         auto acquireFence = fenceFactory.createFenceTimeForTest(fence);
-        const auto buffer = new GraphicBuffer(1, 1, HAL_PIXEL_FORMAT_RGBA_8888, 1, 0);
         BufferData bufferData;
-        bufferData.buffer = buffer;
         bufferData.acquireFence = fence;
         bufferData.frameNumber = 1;
         bufferData.flags |= BufferData::BufferDataChange::fenceChanged;
         bufferData.flags |= BufferData::BufferDataChange::frameNumberChanged;
-        layer->setBuffer(bufferData, 10, 20, false, std::nullopt,
+        std::shared_ptr<renderengine::ExternalTexture> externalTexture = std::make_shared<
+                renderengine::mock::FakeExternalTexture>(1U /*width*/, 1U /*height*/,
+                                                         1ULL /* bufferId */,
+                                                         HAL_PIXEL_FORMAT_RGBA_8888,
+                                                         0ULL /*usage*/);
+        layer->setBuffer(externalTexture, bufferData, 10, 20, false, std::nullopt,
                          {/*vsyncId*/ 3, /*inputEventId*/ 0});
         EXPECT_EQ(2u, layer->mDrawingState.bufferlessSurfaceFramesTX.size());
         ASSERT_NE(nullptr, layer->mDrawingState.bufferSurfaceFrameTX);
@@ -310,27 +329,33 @@
 
         sp<Fence> fence1(new Fence());
         auto acquireFence1 = fenceFactory.createFenceTimeForTest(fence1);
-        const auto buffer1 = new GraphicBuffer(1, 1, HAL_PIXEL_FORMAT_RGBA_8888, 1, 0);
         BufferData bufferData;
-        bufferData.buffer = buffer1;
         bufferData.acquireFence = fence1;
         bufferData.frameNumber = 1;
         bufferData.flags |= BufferData::BufferDataChange::fenceChanged;
         bufferData.flags |= BufferData::BufferDataChange::frameNumberChanged;
-        layer->setBuffer(bufferData, 10, 20, false, std::nullopt,
+        std::shared_ptr<renderengine::ExternalTexture> externalTexture1 = std::make_shared<
+                renderengine::mock::FakeExternalTexture>(1U /*width*/, 1U /*height*/,
+                                                         1ULL /* bufferId */,
+                                                         HAL_PIXEL_FORMAT_RGBA_8888,
+                                                         0ULL /*usage*/);
+        layer->setBuffer(externalTexture1, bufferData, 10, 20, false, std::nullopt,
                          {/*vsyncId*/ 1, /*inputEventId*/ 0});
         ASSERT_NE(nullptr, layer->mDrawingState.bufferSurfaceFrameTX);
         const auto droppedSurfaceFrame = layer->mDrawingState.bufferSurfaceFrameTX;
 
         sp<Fence> fence2(new Fence());
         auto acquireFence2 = fenceFactory.createFenceTimeForTest(fence2);
-        const auto buffer2 = new GraphicBuffer(1, 1, HAL_PIXEL_FORMAT_RGBA_8888, 1, 0);
-        bufferData.buffer = buffer2;
         bufferData.acquireFence = fence2;
         bufferData.frameNumber = 1;
         bufferData.flags |= BufferData::BufferDataChange::fenceChanged;
         bufferData.flags |= BufferData::BufferDataChange::frameNumberChanged;
-        layer->setBuffer(bufferData, 10, 20, false, std::nullopt,
+        std::shared_ptr<renderengine::ExternalTexture> externalTexture2 = std::make_shared<
+                renderengine::mock::FakeExternalTexture>(1U /*width*/, 1U /*height*/,
+                                                         1ULL /* bufferId */,
+                                                         HAL_PIXEL_FORMAT_RGBA_8888,
+                                                         0ULL /*usage*/);
+        layer->setBuffer(externalTexture2, bufferData, 10, 20, false, std::nullopt,
                          {/*vsyncId*/ 1, /*inputEventId*/ 0});
         acquireFence2->signalForTest(12);
 
@@ -356,14 +381,17 @@
 
         sp<Fence> fence1(new Fence());
         auto acquireFence1 = fenceFactory.createFenceTimeForTest(fence1);
-        const auto buffer1 = new GraphicBuffer(1, 1, HAL_PIXEL_FORMAT_RGBA_8888, 1, 0);
         BufferData bufferData;
-        bufferData.buffer = buffer1;
         bufferData.acquireFence = fence1;
         bufferData.frameNumber = 1;
         bufferData.flags |= BufferData::BufferDataChange::fenceChanged;
         bufferData.flags |= BufferData::BufferDataChange::frameNumberChanged;
-        layer->setBuffer(bufferData, 10, 20, false, std::nullopt,
+        std::shared_ptr<renderengine::ExternalTexture> externalTexture1 = std::make_shared<
+                renderengine::mock::FakeExternalTexture>(1U /*width*/, 1U /*height*/,
+                                                         1ULL /* bufferId */,
+                                                         HAL_PIXEL_FORMAT_RGBA_8888,
+                                                         0ULL /*usage*/);
+        layer->setBuffer(externalTexture1, bufferData, 10, 20, false, std::nullopt,
                          {/*vsyncId*/ 1, /*inputEventId*/ 0});
         EXPECT_EQ(0u, layer->mDrawingState.bufferlessSurfaceFramesTX.size());
         ASSERT_NE(nullptr, layer->mDrawingState.bufferSurfaceFrameTX);
@@ -371,14 +399,17 @@
 
         sp<Fence> fence2(new Fence());
         auto acquireFence2 = fenceFactory.createFenceTimeForTest(fence2);
-        const auto buffer2 = new GraphicBuffer(1, 1, HAL_PIXEL_FORMAT_RGBA_8888, 1, 0);
         auto dropStartTime1 = systemTime();
-        bufferData.buffer = buffer2;
         bufferData.acquireFence = fence2;
         bufferData.frameNumber = 1;
         bufferData.flags |= BufferData::BufferDataChange::fenceChanged;
         bufferData.flags |= BufferData::BufferDataChange::frameNumberChanged;
-        layer->setBuffer(bufferData, 10, 20, false, std::nullopt,
+        std::shared_ptr<renderengine::ExternalTexture> externalTexture2 = std::make_shared<
+                renderengine::mock::FakeExternalTexture>(1U /*width*/, 1U /*height*/,
+                                                         1ULL /* bufferId */,
+                                                         HAL_PIXEL_FORMAT_RGBA_8888,
+                                                         0ULL /*usage*/);
+        layer->setBuffer(externalTexture2, bufferData, 10, 20, false, std::nullopt,
                          {/*vsyncId*/ FrameTimelineInfo::INVALID_VSYNC_ID, /*inputEventId*/ 0});
         auto dropEndTime1 = systemTime();
         EXPECT_EQ(0u, layer->mDrawingState.bufferlessSurfaceFramesTX.size());
@@ -387,14 +418,17 @@
 
         sp<Fence> fence3(new Fence());
         auto acquireFence3 = fenceFactory.createFenceTimeForTest(fence3);
-        const auto buffer3 = new GraphicBuffer(1, 1, HAL_PIXEL_FORMAT_RGBA_8888, 1, 0);
         auto dropStartTime2 = systemTime();
-        bufferData.buffer = buffer3;
         bufferData.acquireFence = fence3;
         bufferData.frameNumber = 1;
         bufferData.flags |= BufferData::BufferDataChange::fenceChanged;
         bufferData.flags |= BufferData::BufferDataChange::frameNumberChanged;
-        layer->setBuffer(bufferData, 10, 20, false, std::nullopt,
+        std::shared_ptr<renderengine::ExternalTexture> externalTexture3 = std::make_shared<
+                renderengine::mock::FakeExternalTexture>(1U /*width*/, 1U /*height*/,
+                                                         1ULL /* bufferId */,
+                                                         HAL_PIXEL_FORMAT_RGBA_8888,
+                                                         0ULL /*usage*/);
+        layer->setBuffer(externalTexture3, bufferData, 10, 20, false, std::nullopt,
                          {/*vsyncId*/ 2, /*inputEventId*/ 0});
         auto dropEndTime2 = systemTime();
         acquireFence3->signalForTest(12);
@@ -432,14 +466,17 @@
         std::vector<std::shared_ptr<frametimeline::SurfaceFrame>> bufferlessSurfaceFrames;
         for (int i = 0; i < 10; i += 2) {
             sp<Fence> fence(new Fence());
-            const auto buffer = new GraphicBuffer(1, 1, HAL_PIXEL_FORMAT_RGBA_8888, 1, 0);
             BufferData bufferData;
-            bufferData.buffer = buffer;
             bufferData.acquireFence = fence;
             bufferData.frameNumber = 1;
             bufferData.flags |= BufferData::BufferDataChange::fenceChanged;
             bufferData.flags |= BufferData::BufferDataChange::frameNumberChanged;
-            layer->setBuffer(bufferData, 10, 20, false, std::nullopt,
+            std::shared_ptr<renderengine::ExternalTexture> externalTexture = std::make_shared<
+                    renderengine::mock::FakeExternalTexture>(1U /*width*/, 1U /*height*/,
+                                                             1ULL /* bufferId */,
+                                                             HAL_PIXEL_FORMAT_RGBA_8888,
+                                                             0ULL /*usage*/);
+            layer->setBuffer(externalTexture, bufferData, 10, 20, false, std::nullopt,
                              {/*vsyncId*/ 1, /*inputEventId*/ 0});
             layer->setFrameTimelineVsyncForBufferlessTransaction({/*vsyncId*/ 2,
                                                                   /*inputEventId*/ 0},