Add layer flag to allow creating an effect layer without color fill

This change allows creating an effect layers without a color fill so
we can avoid an additional sf transactions when creating effect
layers.

Fixes: 157646690
Test: go/wm-smoke
Test: atest SurfaceFlinger_test
Change-Id: I3d8a4f4820d7b8fb05daab697c25cff8def612c1
diff --git a/libs/gui/include/gui/ISurfaceComposerClient.h b/libs/gui/include/gui/ISurfaceComposerClient.h
index 6366529..3afbabf 100644
--- a/libs/gui/include/gui/ISurfaceComposerClient.h
+++ b/libs/gui/include/gui/ISurfaceComposerClient.h
@@ -33,7 +33,7 @@
     DECLARE_META_INTERFACE(SurfaceComposerClient)
 
     // flags for createSurface()
-    enum { // (keep in sync with Surface.java)
+    enum { // (keep in sync with SurfaceControl.java)
         eHidden = 0x00000004,
         eDestroyBackbuffer = 0x00000020,
         eSecure = 0x00000080,
@@ -42,6 +42,7 @@
         eProtectedByApp = 0x00000800,
         eProtectedByDRM = 0x00001000,
         eCursorWindow = 0x00002000,
+        eNoColorFill = 0x00004000,
 
         eFXSurfaceBufferQueue = 0x00000000,
         eFXSurfaceEffect = 0x00020000,
diff --git a/services/surfaceflinger/Layer.cpp b/services/surfaceflinger/Layer.cpp
index 5b9dbf2..f3d0b10 100644
--- a/services/surfaceflinger/Layer.cpp
+++ b/services/surfaceflinger/Layer.cpp
@@ -119,6 +119,13 @@
     mCurrentState.treeHasFrameRateVote = false;
     mCurrentState.fixedTransformHint = ui::Transform::ROT_INVALID;
 
+    if (args.flags & ISurfaceComposerClient::eNoColorFill) {
+        // Set an invalid color so there is no color fill.
+        mCurrentState.color.r = -1.0_hf;
+        mCurrentState.color.g = -1.0_hf;
+        mCurrentState.color.b = -1.0_hf;
+    }
+
     // drawing state & current state are identical
     mDrawingState = mCurrentState;
 
diff --git a/services/surfaceflinger/tests/Android.bp b/services/surfaceflinger/tests/Android.bp
index 94ebe89..fe2af80 100644
--- a/services/surfaceflinger/tests/Android.bp
+++ b/services/surfaceflinger/tests/Android.bp
@@ -22,6 +22,7 @@
         "Credentials_test.cpp",
         "DereferenceSurfaceControl_test.cpp",
         "DisplayConfigs_test.cpp",
+        "EffectLayer_test.cpp",
         "InvalidHandles_test.cpp",
         "LayerCallback_test.cpp",
         "LayerRenderTypeTransaction_test.cpp",
diff --git a/services/surfaceflinger/tests/EffectLayer_test.cpp b/services/surfaceflinger/tests/EffectLayer_test.cpp
new file mode 100644
index 0000000..3dca391
--- /dev/null
+++ b/services/surfaceflinger/tests/EffectLayer_test.cpp
@@ -0,0 +1,117 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// TODO(b/129481165): remove the #pragma below and fix conversion issues
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wconversion"
+
+#include "LayerTransactionTest.h"
+
+namespace android {
+
+class EffectLayerTest : public LayerTransactionTest {
+protected:
+    virtual void SetUp() {
+        LayerTransactionTest::SetUp();
+        ASSERT_EQ(NO_ERROR, mClient->initCheck());
+
+        const auto display = SurfaceComposerClient::getInternalDisplayToken();
+        ASSERT_FALSE(display == nullptr);
+
+        mParentLayer = createColorLayer("Parent layer", Color::RED);
+        asTransaction([&](Transaction& t) {
+            t.setDisplayLayerStack(display, 0);
+            t.setLayer(mParentLayer, INT32_MAX - 2).show(mParentLayer);
+            t.setFlags(mParentLayer, layer_state_t::eLayerOpaque, layer_state_t::eLayerOpaque);
+        });
+    }
+
+    virtual void TearDown() {
+        LayerTransactionTest::TearDown();
+        mParentLayer = 0;
+    }
+
+    sp<SurfaceControl> mParentLayer;
+};
+
+TEST_F(EffectLayerTest, DefaultEffectLayerHasSolidBlackFill) {
+    sp<SurfaceControl> effectLayer =
+            mClient->createSurface(String8("Effect Layer"), 0 /* width */, 0 /* height */,
+                                   PIXEL_FORMAT_RGBA_8888, ISurfaceComposerClient::eFXSurfaceEffect,
+                                   mParentLayer.get());
+
+    EXPECT_NE(nullptr, effectLayer.get()) << "failed to create SurfaceControl";
+    asTransaction([&](Transaction& t) {
+        t.setCrop_legacy(effectLayer, Rect(0, 0, 400, 400));
+        t.show(effectLayer);
+    });
+
+    {
+        SCOPED_TRACE("Default effect Layer has solid black fill");
+        auto shot = screenshot();
+        shot->expectColor(Rect(0, 0, 400, 400), Color::BLACK);
+    }
+}
+
+TEST_F(EffectLayerTest, EffectLayerWithNoFill) {
+    sp<SurfaceControl> effectLayer =
+            mClient->createSurface(String8("Effect Layer"), 0 /* width */, 0 /* height */,
+                                   PIXEL_FORMAT_RGBA_8888,
+                                   ISurfaceComposerClient::eFXSurfaceEffect |
+                                           ISurfaceComposerClient::eNoColorFill,
+                                   mParentLayer.get());
+
+    EXPECT_NE(nullptr, effectLayer.get()) << "failed to create SurfaceControl";
+    asTransaction([&](Transaction& t) {
+        t.setCrop_legacy(effectLayer, Rect(0, 0, 400, 400));
+        t.show(effectLayer);
+    });
+
+    {
+        SCOPED_TRACE("Effect layer with nofill option is transparent");
+        auto shot = screenshot();
+        shot->expectColor(Rect(0, 0, 400, 400), Color::RED);
+    }
+}
+
+TEST_F(EffectLayerTest, EffectLayerCanSetColor) {
+    sp<SurfaceControl> effectLayer =
+            mClient->createSurface(String8("Effect Layer"), 0 /* width */, 0 /* height */,
+                                   PIXEL_FORMAT_RGBA_8888,
+                                   ISurfaceComposerClient::eFXSurfaceEffect |
+                                           ISurfaceComposerClient::eNoColorFill,
+                                   mParentLayer.get());
+
+    EXPECT_NE(nullptr, effectLayer.get()) << "failed to create SurfaceControl";
+    asTransaction([&](Transaction& t) {
+        t.setCrop_legacy(effectLayer, Rect(0, 0, 400, 400));
+        t.setColor(effectLayer,
+                   half3{Color::GREEN.r / 255.0f, Color::GREEN.g / 255.0f,
+                         Color::GREEN.b / 255.0f});
+        t.show(effectLayer);
+    });
+
+    {
+        SCOPED_TRACE("Effect Layer can set color");
+        auto shot = screenshot();
+        shot->expectColor(Rect(0, 0, 400, 400), Color::GREEN);
+    }
+}
+
+} // namespace android
+
+// TODO(b/129481165): remove the #pragma below and fix conversion issues
+#pragma clang diagnostic pop // ignored "-Wconversion"