Set blockingRegion for DISPLAY_DECORATION layers
Devices that have support for DISPLAY_DECORATION layers may also have
support for a blockingRegion, which will allow the DPU to skip regions
that are known to be transparent, in order to save power.
Use the transparentRegionHint to compute the blockingRegion. It may not
be accurate for all layers, which is why it is only used for
DISPLAY_DECORATION layers.
Add tests.
Bug: 212736475
Test: libcompositionengine_test
Change-Id: I6c5d29614dc8d65d8481150ce717a440192083a0
diff --git a/services/surfaceflinger/CompositionEngine/src/Output.cpp b/services/surfaceflinger/CompositionEngine/src/Output.cpp
index 162d84e..65f9731 100644
--- a/services/surfaceflinger/CompositionEngine/src/Output.cpp
+++ b/services/surfaceflinger/CompositionEngine/src/Output.cpp
@@ -50,6 +50,8 @@
#include "TracedOrdinal.h"
+using aidl::android::hardware::graphics::composer3::Composition;
+
namespace android::compositionengine {
Output::~Output() = default;
@@ -529,11 +531,18 @@
/*
* transparentRegion: area of a surface that is hinted to be completely
- * transparent. This is only used to tell when the layer has no visible non-
- * transparent regions and can be removed from the layer list. It does not
- * affect the visibleRegion of this layer or any layers beneath it. The hint
- * may not be correct if apps don't respect the SurfaceView restrictions
- * (which, sadly, some don't).
+ * transparent.
+ * This is used to tell when the layer has no visible non-transparent
+ * regions and can be removed from the layer list. It does not affect the
+ * visibleRegion of this layer or any layers beneath it. The hint may not
+ * be correct if apps don't respect the SurfaceView restrictions (which,
+ * sadly, some don't).
+ *
+ * In addition, it is used on DISPLAY_DECORATION layers to specify the
+ * blockingRegion, allowing the DPU to skip it to save power. Once we have
+ * hardware that supports a blockingRegion on frames with AFBC, it may be
+ * useful to use this for other layers, too, so long as we can prevent
+ * regressions on b/7179570.
*/
Region transparentRegion;
@@ -674,6 +683,9 @@
outputLayerState.outputSpaceVisibleRegion = outputState.transform.transform(
visibleNonShadowRegion.intersect(outputState.layerStackSpace.getContent()));
outputLayerState.shadowRegion = shadowRegion;
+ outputLayerState.outputSpaceBlockingRegionHint =
+ layerFEState->compositionType == Composition::DISPLAY_DECORATION ? transparentRegion
+ : Region();
}
void Output::setReleasedLayers(const compositionengine::CompositionRefreshArgs&) {