libgui: add layer_state_t::diff

Compares two layer_state_t structs and returns
a set of change flags describing all the states
that are different.

Also introduces change sets describing which
set of client states can affect the hierarchy,
content or the content size.

Bug: 238781169
Test: presubmit
Change-Id: I6e5fb255972aff2373be27e62005ee3a8de7ebf6

1 files changed, 89 insertions, 0 deletions

diff --git a/libs/gui/LayerState.cpp b/libs/gui/LayerState.cpp
index 924e65ec4a..95962afda1 100644
--- a/libs/gui/LayerState.cpp
+++ b/libs/gui/LayerState.cpp
@@ -24,10 +24,31 @@
 #include <binder/Parcel.h>
 #include <gui/IGraphicBufferProducer.h>
 #include <gui/LayerState.h>
+#include <gui/SurfaceControl.h>
 #include <private/gui/ParcelUtils.h>
 #include <system/window.h>
 #include <utils/Errors.h>
 
+#define CHECK_DIFF(DIFF_RESULT, CHANGE_FLAG, OTHER, FIELD)          \
+    {                                                               \
+        if ((OTHER.what & CHANGE_FLAG) && (FIELD != OTHER.FIELD)) { \
+            DIFF_RESULT |= CHANGE_FLAG;                             \
+        }                                                           \
+    }
+
+#define CHECK_DIFF2(DIFF_RESULT, CHANGE_FLAG, OTHER, FIELD1, FIELD2) \
+    {                                                                \
+        CHECK_DIFF(DIFF_RESULT, CHANGE_FLAG, OTHER, FIELD1)          \
+        CHECK_DIFF(DIFF_RESULT, CHANGE_FLAG, OTHER, FIELD2)          \
+    }
+
+#define CHECK_DIFF3(DIFF_RESULT, CHANGE_FLAG, OTHER, FIELD1, FIELD2, FIELD3) \
+    {                                                                        \
+        CHECK_DIFF(DIFF_RESULT, CHANGE_FLAG, OTHER, FIELD1)                  \
+        CHECK_DIFF(DIFF_RESULT, CHANGE_FLAG, OTHER, FIELD2)                  \
+        CHECK_DIFF(DIFF_RESULT, CHANGE_FLAG, OTHER, FIELD3)                  \
+    }
+
 namespace android {
 
 using gui::FocusRequest;
@@ -626,6 +647,74 @@ void layer_state_t::merge(const layer_state_t& other) {
     }
 }
 
+uint64_t layer_state_t::diff(const layer_state_t& other) const {
+    uint64_t diff = 0;
+    CHECK_DIFF2(diff, ePositionChanged, other, x, y);
+    if (other.what & eLayerChanged) {
+        diff |= eLayerChanged;
+        diff &= ~eRelativeLayerChanged;
+    }
+    CHECK_DIFF(diff, eAlphaChanged, other, color.a);
+    CHECK_DIFF(diff, eMatrixChanged, other, matrix);
+    if (other.what & eTransparentRegionChanged &&
+        (!transparentRegion.hasSameRects(other.transparentRegion))) {
+        diff |= eTransparentRegionChanged;
+    }
+    if (other.what & eFlagsChanged) {
+        uint64_t changedFlags = (flags & other.mask) ^ (other.flags & other.mask);
+        if (changedFlags) diff |= eFlagsChanged;
+    }
+    CHECK_DIFF(diff, eLayerStackChanged, other, layerStack);
+    CHECK_DIFF(diff, eCornerRadiusChanged, other, cornerRadius);
+    CHECK_DIFF(diff, eBackgroundBlurRadiusChanged, other, backgroundBlurRadius);
+    if (other.what & eBlurRegionsChanged) diff |= eBlurRegionsChanged;
+    if (other.what & eRelativeLayerChanged) {
+        diff |= eRelativeLayerChanged;
+        diff &= ~eLayerChanged;
+    }
+    if (other.what & eReparent &&
+        !SurfaceControl::isSameSurface(parentSurfaceControlForChild,
+                                       other.parentSurfaceControlForChild)) {
+        diff |= eReparent;
+    }
+    CHECK_DIFF(diff, eBufferTransformChanged, other, bufferTransform);
+    CHECK_DIFF(diff, eTransformToDisplayInverseChanged, other, transformToDisplayInverse);
+    CHECK_DIFF(diff, eCropChanged, other, crop);
+    if (other.what & eBufferChanged) diff |= eBufferChanged;
+    CHECK_DIFF(diff, eDataspaceChanged, other, dataspace);
+    CHECK_DIFF(diff, eHdrMetadataChanged, other, hdrMetadata);
+    if (other.what & eSurfaceDamageRegionChanged &&
+        (!surfaceDamageRegion.hasSameRects(other.surfaceDamageRegion))) {
+        diff |= eSurfaceDamageRegionChanged;
+    }
+    CHECK_DIFF(diff, eApiChanged, other, api);
+    if (other.what & eSidebandStreamChanged) diff |= eSidebandStreamChanged;
+    CHECK_DIFF(diff, eApiChanged, other, api);
+    CHECK_DIFF(diff, eColorTransformChanged, other, colorTransform);
+    if (other.what & eHasListenerCallbacksChanged) diff |= eHasListenerCallbacksChanged;
+    if (other.what & eInputInfoChanged) diff |= eInputInfoChanged;
+    CHECK_DIFF3(diff, eBackgroundColorChanged, other, color.rgb, bgColorAlpha, bgColorDataspace);
+    if (other.what & eMetadataChanged) diff |= eMetadataChanged;
+    CHECK_DIFF(diff, eShadowRadiusChanged, other, shadowRadius);
+    CHECK_DIFF3(diff, eRenderBorderChanged, other, borderEnabled, borderWidth, borderColor);
+    CHECK_DIFF(diff, eDefaultFrameRateCompatibilityChanged, other, defaultFrameRateCompatibility);
+    CHECK_DIFF(diff, eFrameRateSelectionPriority, other, frameRateSelectionPriority);
+    CHECK_DIFF3(diff, eFrameRateChanged, other, frameRate, frameRateCompatibility,
+                changeFrameRateStrategy);
+    CHECK_DIFF(diff, eFixedTransformHintChanged, other, fixedTransformHint);
+    CHECK_DIFF(diff, eAutoRefreshChanged, other, autoRefresh);
+    CHECK_DIFF(diff, eTrustedOverlayChanged, other, isTrustedOverlay);
+    CHECK_DIFF(diff, eStretchChanged, other, stretchEffect);
+    CHECK_DIFF(diff, eBufferCropChanged, other, bufferCrop);
+    CHECK_DIFF(diff, eDestinationFrameChanged, other, destinationFrame);
+    if (other.what & eProducerDisconnect) diff |= eProducerDisconnect;
+    CHECK_DIFF(diff, eDropInputModeChanged, other, dropInputMode);
+    CHECK_DIFF(diff, eColorChanged, other, color.rgb);
+    CHECK_DIFF(diff, eColorSpaceAgnosticChanged, other, colorSpaceAgnostic);
+    CHECK_DIFF(diff, eDimmingEnabledChanged, other, dimmingEnabled);
+    return diff;
+}
+
 bool layer_state_t::hasBufferChanges() const {
     return what & layer_state_t::eBufferChanged;
 }