latch transparent region hint only when we get a new frame
since the transparent region hint really depends on the
content of the window containing the SurfaceView
(it's calculated by the view hierarchy based on
overlapping views), it makes sense to latch it only when
the content of the window (the app) changes.
This should help fixing drawing artifacts when changing the
layout of a window containing a SurfaceView.
Bug: 8511430
Change-Id: Ic3aa668495293cb4d82a2cd7dcf3b6a337287678
diff --git a/include/ui/Region.h b/include/ui/Region.h
index ffcd429..ce91f3b 100644
--- a/include/ui/Region.h
+++ b/include/ui/Region.h
@@ -108,6 +108,10 @@
inline Region& operator += (const Point& pt);
+ // returns true if the regions share the same underlying storage
+ bool isTriviallyEqual(const Region& region) const;
+
+
/* various ways to access the rectangle list */
diff --git a/libs/ui/Region.cpp b/libs/ui/Region.cpp
index 488fba3..bf01488 100644
--- a/libs/ui/Region.cpp
+++ b/libs/ui/Region.cpp
@@ -239,6 +239,10 @@
mStorage.add(Rect(w,h));
}
+bool Region::isTriviallyEqual(const Region& region) const {
+ return begin() == region.begin();
+}
+
// ----------------------------------------------------------------------------
void Region::addRectUnchecked(int l, int t, int r, int b)
diff --git a/services/surfaceflinger/Layer.cpp b/services/surfaceflinger/Layer.cpp
index a4c613c..2302367 100644
--- a/services/surfaceflinger/Layer.cpp
+++ b/services/surfaceflinger/Layer.cpp
@@ -881,8 +881,7 @@
return true;
}
bool Layer::setTransparentRegionHint(const Region& transparent) {
- mCurrentState.sequence++;
- mCurrentState.transparentRegion = transparent;
+ mCurrentState.requestedTransparentRegion = transparent;
setTransactionFlags(eTransactionNeeded);
return true;
}
@@ -1008,7 +1007,6 @@
swap(bufWidth, bufHeight);
}
-
bool isFixedSize = item.mScalingMode != NATIVE_WINDOW_SCALING_MODE_FREEZE;
if (front.active != front.requested) {
@@ -1061,6 +1059,17 @@
return true;
}
}
+
+ // if the transparent region has changed (this test is
+ // conservative, but that's fine, worst case we're doing
+ // a bit of extra work), we latch the new one and we
+ // trigger a visible-region recompute.
+ if (!front.activeTransparentRegion.isTriviallyEqual(
+ front.requestedTransparentRegion)) {
+ front.activeTransparentRegion = front.requestedTransparentRegion;
+ recomputeVisibleRegions = true;
+ }
+
return false;
}
};
@@ -1168,7 +1177,7 @@
getTypeId(), this, getName().string());
result.append(buffer);
- s.transparentRegion.dump(result, "transparentRegion");
+ s.activeTransparentRegion.dump(result, "transparentRegion");
visibleRegion.dump(result, "visibleRegion");
sp<Client> client(mClientRef.promote());
diff --git a/services/surfaceflinger/Layer.h b/services/surfaceflinger/Layer.h
index 6bca941..2765db1 100644
--- a/services/surfaceflinger/Layer.h
+++ b/services/surfaceflinger/Layer.h
@@ -103,7 +103,11 @@
uint8_t reserved[2];
int32_t sequence; // changes when visible regions can change
Transform transform;
- Region transparentRegion;
+ // the transparentRegion hint is a bit special, it's latched only
+ // when we receive a buffer -- this is because it's "content"
+ // dependent.
+ Region activeTransparentRegion;
+ Region requestedTransparentRegion;
};
class LayerMesh {
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 3ed8b1b..5c7cf07 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -1360,14 +1360,14 @@
if (tr.transformed()) {
if (tr.preserveRects()) {
// transform the transparent region
- transparentRegion = tr.transform(s.transparentRegion);
+ transparentRegion = tr.transform(s.activeTransparentRegion);
} else {
// transformation too complex, can't do the
// transparent region optimization.
transparentRegion.clear();
}
} else {
- transparentRegion = s.transparentRegion;
+ transparentRegion = s.activeTransparentRegion;
}
}