Merge "SurfaceFlinger: setGeometryAppliesWithResize crop latching fixes." into oc-dev
diff --git a/services/surfaceflinger/Layer.cpp b/services/surfaceflinger/Layer.cpp
index 06a0765..50d8998 100644
--- a/services/surfaceflinger/Layer.cpp
+++ b/services/surfaceflinger/Layer.cpp
@@ -103,7 +103,7 @@
         mLastFrameNumberReceived(0),
         mUpdateTexImageFailed(false),
         mAutoRefresh(false),
-        mFreezePositionUpdates(false)
+        mFreezeGeometryUpdates(false)
 {
 #ifdef USE_HWC2
     ALOGV("Creating Layer %s", name.string());
@@ -131,6 +131,8 @@
     mCurrentState.active.transform.set(0, 0);
     mCurrentState.crop.makeInvalid();
     mCurrentState.finalCrop.makeInvalid();
+    mCurrentState.requestedFinalCrop = mCurrentState.finalCrop;
+    mCurrentState.requestedCrop = mCurrentState.crop;
     mCurrentState.z = 0;
 #ifdef USE_HWC2
     mCurrentState.alpha = 1.0f;
@@ -1636,12 +1638,25 @@
         }
     }
 
-    // always set active to requested, unless we're asked not to
-    // this is used by Layer, which special cases resizes.
-    if (flags & eDontUpdateGeometryState)  {
-    } else {
+    // Here we apply various requested geometry states, depending on our
+    // latching configuration. See Layer.h for a detailed discussion of
+    // how geometry latching is controlled.
+    if (!(flags & eDontUpdateGeometryState)) {
         Layer::State& editCurrentState(getCurrentState());
-        if (mFreezePositionUpdates) {
+
+        // If mFreezeGeometryUpdates is true we are in the setGeometryAppliesWithResize
+        // mode, which causes attributes which normally latch regardless of scaling mode,
+        // to be delayed. We copy the requested state to the active state making sure
+        // to respect these rules (again see Layer.h for a detailed discussion).
+        //
+        // There is an awkward asymmetry in the handling of the crop states in the position
+        // states, as can be seen below. Largely this arises from position and transform
+        // being stored in the same data structure while having different latching rules.
+        // b/38182305
+        //
+        // Careful that "c" and editCurrentState may not begin as equivalent due to
+        // applyPendingStates in the presence of deferred transactions.
+        if (mFreezeGeometryUpdates) {
             float tx = c.active.transform.tx();
             float ty = c.active.transform.ty();
             c.active = c.requested;
@@ -1650,6 +1665,14 @@
         } else {
             editCurrentState.active = editCurrentState.requested;
             c.active = c.requested;
+            if (c.crop != c.requestedCrop ||
+                    c.finalCrop != c.requestedFinalCrop) {
+                c.sequence++;
+                c.crop = c.requestedCrop;
+                c.finalCrop = c.requestedFinalCrop;
+                editCurrentState.crop = c.crop;
+                editCurrentState.finalCrop = c.finalCrop;
+            }
         }
     }
 
@@ -1702,10 +1725,14 @@
     // we want to apply the position portion of the transform matrix immediately,
     // but still delay scaling when resizing a SCALING_MODE_FREEZE layer.
     mCurrentState.requested.transform.set(x, y);
-    if (immediate && !mFreezePositionUpdates) {
+    if (immediate && !mFreezeGeometryUpdates) {
+        // Here we directly update the active state
+        // unlike other setters, because we store it within
+        // the transform, but use different latching rules.
+        // b/38182305
         mCurrentState.active.transform.set(x, y);
     }
-    mFreezePositionUpdates = mFreezePositionUpdates || !immediate;
+    mFreezeGeometryUpdates = mFreezeGeometryUpdates || !immediate;
 
     mCurrentState.modified = true;
     setTransactionFlags(eTransactionNeeded);
@@ -1828,26 +1855,30 @@
 }
 
 bool Layer::setCrop(const Rect& crop, bool immediate) {
-    if (mCurrentState.crop == crop)
+    if (mCurrentState.requestedCrop == crop)
         return false;
     mCurrentState.sequence++;
     mCurrentState.requestedCrop = crop;
-    if (immediate) {
+    if (immediate && !mFreezeGeometryUpdates) {
         mCurrentState.crop = crop;
     }
+    mFreezeGeometryUpdates = mFreezeGeometryUpdates || !immediate;
+
     mCurrentState.modified = true;
     setTransactionFlags(eTransactionNeeded);
     return true;
 }
 
 bool Layer::setFinalCrop(const Rect& crop, bool immediate) {
-    if (mCurrentState.finalCrop == crop)
+    if (mCurrentState.requestedFinalCrop == crop)
         return false;
     mCurrentState.sequence++;
     mCurrentState.requestedFinalCrop = crop;
-    if (immediate) {
+    if (immediate && !mFreezeGeometryUpdates) {
         mCurrentState.finalCrop = crop;
     }
+    mFreezeGeometryUpdates = mFreezeGeometryUpdates || !immediate;
+
     mCurrentState.modified = true;
     setTransactionFlags(eTransactionNeeded);
     return true;
@@ -2137,7 +2168,7 @@
     bool queuedBuffer = false;
     LayerRejecter r(mDrawingState, getCurrentState(), recomputeVisibleRegions,
                     getProducerStickyTransform() != 0, mName.string(),
-                    mOverrideScalingMode, mFreezePositionUpdates);
+                    mOverrideScalingMode, mFreezeGeometryUpdates);
     status_t updateResult = mSurfaceFlingerConsumer->updateTexImage(&r,
             mFlinger->mPrimaryDispSync, &mAutoRefresh, &queuedBuffer,
             mLastFrameNumberReceived);
diff --git a/services/surfaceflinger/Layer.h b/services/surfaceflinger/Layer.h
index 9f45435..513ddff 100644
--- a/services/surfaceflinger/Layer.h
+++ b/services/surfaceflinger/Layer.h
@@ -169,25 +169,64 @@
     // the this layer's size and format
     status_t setBuffers(uint32_t w, uint32_t h, PixelFormat format, uint32_t flags);
 
-    // modify current state
+    // ------------------------------------------------------------------------
+    // Geometry setting functions.
+    //
+    // The following group of functions are used to specify the layers
+    // bounds, and the mapping of the texture on to those bounds. According
+    // to various settings changes to them may apply immediately, or be delayed until
+    // a pending resize is completed by the producer submitting a buffer. For example
+    // if we were to change the buffer size, and update the matrix ahead of the
+    // new buffer arriving, then we would be stretching the buffer to a different
+    // aspect before and after the buffer arriving, which probably isn't what we wanted.
+    //
+    // The first set of geometry functions are controlled by the scaling mode, described
+    // in window.h. The scaling mode may be set by the client, as it submits buffers.
+    // This value may be overriden through SurfaceControl, with setOverrideScalingMode.
+    //
+    // Put simply, if our scaling mode is SCALING_MODE_FREEZE, then
+    // matrix updates will not be applied while a resize is pending
+    // and the size and transform will remain in their previous state
+    // until a new buffer is submitted. If the scaling mode is another value
+    // then the old-buffer will immediately be scaled to the pending size
+    // and the new matrix will be immediately applied following this scaling
+    // transformation.
 
-    // These members of state (position, crop, and finalCrop)
-    // may be updated immediately or have the update delayed
-    // until a pending surface resize completes (if applicable).
+    // Set the default buffer size for the assosciated Producer, in pixels. This is
+    // also the rendered size of the layer prior to any transformations. Parent
+    // or local matrix transformations will not affect the size of the buffer,
+    // but may affect it's on-screen size or clipping.
+    bool setSize(uint32_t w, uint32_t h);
+    // Set a 2x2 transformation matrix on the layer. This transform
+    // will be applied after parent transforms, but before any final
+    // producer specified transform.
+    bool setMatrix(const layer_state_t::matrix22_t& matrix);
+
+    // This second set of geometry attributes are controlled by
+    // setGeometryAppliesWithResize, and their default mode is to be
+    // immediate. If setGeometryAppliesWithResize is specified
+    // while a resize is pending, then update of these attributes will
+    // be delayed until the resize completes.
+    
+    // setPosition operates in parent buffer space (pre parent-transform) or display
+    // space for top-level layers.
     bool setPosition(float x, float y, bool immediate);
+    // Buffer space
     bool setCrop(const Rect& crop, bool immediate);
+    // Parent buffer space/display space
     bool setFinalCrop(const Rect& crop, bool immediate);
 
+    // TODO(b/38182121): Could we eliminate the various latching modes by
+    // using the layer hierarchy?
+    // -----------------------------------------------------------------------
     bool setLayer(int32_t z);
     bool setRelativeLayer(const sp<IBinder>& relativeToHandle, int32_t relativeZ);
 
-    bool setSize(uint32_t w, uint32_t h);
 #ifdef USE_HWC2
     bool setAlpha(float alpha);
 #else
     bool setAlpha(uint8_t alpha);
 #endif
-    bool setMatrix(const layer_state_t::matrix22_t& matrix);
     bool setTransparentRegionHint(const Region& transparent);
     bool setFlags(uint8_t flags, uint8_t mask);
     bool setLayerStack(uint32_t layerStack);
@@ -754,7 +793,7 @@
     bool mUpdateTexImageFailed; // This is only accessed on the main thread.
 
     bool mAutoRefresh;
-    bool mFreezePositionUpdates;
+    bool mFreezeGeometryUpdates;
 
     // Child list about to be committed/used for editing.
     LayerVector mCurrentChildren;
diff --git a/services/surfaceflinger/LayerRejecter.cpp b/services/surfaceflinger/LayerRejecter.cpp
index 0b302eb..b2424d0 100644
--- a/services/surfaceflinger/LayerRejecter.cpp
+++ b/services/surfaceflinger/LayerRejecter.cpp
@@ -37,7 +37,7 @@
     mStickyTransformSet(stickySet),
     mName(name),
     mOverrideScalingMode(overrideScalingMode),
-    mFreezePositionUpdates(freezePositionUpdates) {}
+    mFreezeGeometryUpdates(freezePositionUpdates) {}
 
 bool LayerRejecter::reject(const sp<GraphicBuffer>& buf, const BufferItem& item) {
     if (buf == NULL) {
@@ -115,17 +115,7 @@
         mRecomputeVisibleRegions = true;
     }
 
-    if (mFront.crop != mFront.requestedCrop) {
-        mFront.crop = mFront.requestedCrop;
-        mCurrent.crop = mFront.requestedCrop;
-        mRecomputeVisibleRegions = true;
-    }
-    if (mFront.finalCrop != mFront.requestedFinalCrop) {
-        mFront.finalCrop = mFront.requestedFinalCrop;
-        mCurrent.finalCrop = mFront.requestedFinalCrop;
-        mRecomputeVisibleRegions = true;
-    }
-    mFreezePositionUpdates = false;
+    mFreezeGeometryUpdates = false;
 
     return false;
 }
diff --git a/services/surfaceflinger/LayerRejecter.h b/services/surfaceflinger/LayerRejecter.h
index c2a9483..828cd8b 100644
--- a/services/surfaceflinger/LayerRejecter.h
+++ b/services/surfaceflinger/LayerRejecter.h
@@ -40,8 +40,8 @@
         bool mStickyTransformSet;
         const char *mName;
         int32_t mOverrideScalingMode;
-        bool &mFreezePositionUpdates;
+        bool &mFreezeGeometryUpdates;
     };
 }  // namespace android
 
-#endif  // ANDROID_LAYER_REJECTER_H
\ No newline at end of file
+#endif  // ANDROID_LAYER_REJECTER_H
diff --git a/services/surfaceflinger/tests/Transaction_test.cpp b/services/surfaceflinger/tests/Transaction_test.cpp
index 1b17e55..eaf082d 100644
--- a/services/surfaceflinger/tests/Transaction_test.cpp
+++ b/services/surfaceflinger/tests/Transaction_test.cpp
@@ -605,6 +605,27 @@
     EXPECT_CROPPED_STATE("after the resize finishes");
 }
 
+TEST_F(CropLatchingTest, FinalCropLatchingRegressionForb37531386) {
+    EXPECT_INITIAL_STATE("before anything");
+    // In this scenario, we attempt to set the final crop a second time while the resize
+    // is still pending, and ensure we are successful.
+    SurfaceComposerClient::openGlobalTransaction();
+    mFGSurfaceControl->setSize(128, 128);
+    mFGSurfaceControl->setGeometryAppliesWithResize();
+    mFGSurfaceControl->setFinalCrop(Rect(64, 64, 127, 127));
+    SurfaceComposerClient::closeGlobalTransaction(true);
+
+    SurfaceComposerClient::openGlobalTransaction();
+    mFGSurfaceControl->setFinalCrop(Rect(0, 0, -1, -1));
+    SurfaceComposerClient::closeGlobalTransaction(true);
+
+    EXPECT_INITIAL_STATE("after setting crops with geometryAppliesWithResize");
+
+    completeFGResize();
+
+    EXPECT_INITIAL_STATE("after the resize finishes");
+}
+
 TEST_F(LayerUpdateTest, DeferredTransactionTest) {
     sp<ScreenCapture> sc;
     {