Add setBackdropRenderEffect for View and RenderNode.

support visual effects for backdrop contents of a View or RenderNode.

Test: added unit test & hwui_unit passes
Test: added BackdropBlurActivity in HwAccelerationTest, build & run it

Signed-off-by: Dongya Jiang <jiangdongya@coolpad.com>
Change-Id: If1ac1b8aee53667f175e8fa80ecfc7bdfa28173d
Merged-In: If1ac1b8aee53667f175e8fa80ecfc7bdfa28173d

11 files changed, 278 insertions, 6 deletions

diff --git a/libs/hwui/Android.bp b/libs/hwui/Android.bp
index db581471e2ca..b5e6f94af022 100644
--- a/libs/hwui/Android.bp
+++ b/libs/hwui/Android.bp
@@ -514,6 +514,7 @@ cc_defaults {
         "canvas/CanvasOpRasterizer.cpp",
         "effects/StretchEffect.cpp",
         "effects/GainmapRenderer.cpp",
+        "pipeline/skia/BackdropFilterDrawable.cpp",
         "pipeline/skia/HolePunch.cpp",
         "pipeline/skia/SkiaDisplayList.cpp",
         "pipeline/skia/SkiaRecordingCanvas.cpp",
diff --git a/libs/hwui/RenderNode.cpp b/libs/hwui/RenderNode.cpp
index 1c39db3a31bb..1dd22cf43c5c 100644
--- a/libs/hwui/RenderNode.cpp
+++ b/libs/hwui/RenderNode.cpp
@@ -260,6 +260,12 @@ void RenderNode::prepareTreeImpl(TreeObserver& observer, TreeInfo& info, bool fu
         pushStagingDisplayListChanges(observer, info);
     }
 
+    // always damageSelf when filtering backdrop content, or else the BackdropFilterDrawable will
+    // get a wrong snapshot of previous content.
+    if (mProperties.layerProperties().getBackdropImageFilter()) {
+        damageSelf(info);
+    }
+
     if (mDisplayList) {
         info.out.hasFunctors |= mDisplayList.hasFunctor();
         mHasHolePunches = mDisplayList.hasHolePunches();
diff --git a/libs/hwui/RenderProperties.cpp b/libs/hwui/RenderProperties.cpp
index 0589f136b666..c5371236b9cf 100644
--- a/libs/hwui/RenderProperties.cpp
+++ b/libs/hwui/RenderProperties.cpp
@@ -55,6 +55,12 @@ bool LayerProperties::setImageFilter(SkImageFilter* imageFilter) {
     return true;
 }
 
+bool LayerProperties::setBackdropImageFilter(SkImageFilter* imageFilter) {
+    if (mBackdropImageFilter.get() == imageFilter) return false;
+    mBackdropImageFilter = sk_ref_sp(imageFilter);
+    return true;
+}
+
 bool LayerProperties::setFromPaint(const SkPaint* paint) {
     bool changed = false;
     changed |= setAlpha(static_cast<uint8_t>(PaintUtils::getAlphaDirect(paint)));
@@ -70,6 +76,7 @@ LayerProperties& LayerProperties::operator=(const LayerProperties& other) {
     setXferMode(other.xferMode());
     setColorFilter(other.getColorFilter());
     setImageFilter(other.getImageFilter());
+    setBackdropImageFilter(other.getBackdropImageFilter());
     mStretchEffect = other.mStretchEffect;
     return *this;
 }
diff --git a/libs/hwui/RenderProperties.h b/libs/hwui/RenderProperties.h
index 064ba7aee107..e358b57f6fe1 100644
--- a/libs/hwui/RenderProperties.h
+++ b/libs/hwui/RenderProperties.h
@@ -97,8 +97,12 @@ public:
 
     bool setImageFilter(SkImageFilter* imageFilter);
 
+    bool setBackdropImageFilter(SkImageFilter* imageFilter);
+
     SkImageFilter* getImageFilter() const { return mImageFilter.get(); }
 
+    SkImageFilter* getBackdropImageFilter() const { return mBackdropImageFilter.get(); }
+
     const StretchEffect& getStretchEffect() const { return mStretchEffect; }
 
     StretchEffect& mutableStretchEffect() { return mStretchEffect; }
@@ -129,6 +133,7 @@ private:
     SkBlendMode mMode;
     sk_sp<SkColorFilter> mColorFilter;
     sk_sp<SkImageFilter> mImageFilter;
+    sk_sp<SkImageFilter> mBackdropImageFilter;
     StretchEffect mStretchEffect;
 };
 
diff --git a/libs/hwui/jni/android_graphics_RenderNode.cpp b/libs/hwui/jni/android_graphics_RenderNode.cpp
index 8c7b9a4b5e94..2a218a25913d 100644
--- a/libs/hwui/jni/android_graphics_RenderNode.cpp
+++ b/libs/hwui/jni/android_graphics_RenderNode.cpp
@@ -243,6 +243,13 @@ static jboolean android_view_RenderNode_setRenderEffect(CRITICAL_JNI_PARAMS_COMM
     return SET_AND_DIRTY(mutateLayerProperties().setImageFilter, imageFilter, RenderNode::GENERIC);
 }
 
+static jboolean android_view_RenderNode_setBackdropRenderEffect(
+        CRITICAL_JNI_PARAMS_COMMA jlong renderNodePtr, jlong renderEffectPtr) {
+    SkImageFilter* imageFilter = reinterpret_cast<SkImageFilter*>(renderEffectPtr);
+    return SET_AND_DIRTY(mutateLayerProperties().setBackdropImageFilter, imageFilter,
+                         RenderNode::GENERIC);
+}
+
 static jboolean android_view_RenderNode_setHasOverlappingRendering(CRITICAL_JNI_PARAMS_COMMA jlong renderNodePtr,
         bool hasOverlappingRendering) {
     return SET_AND_DIRTY(setHasOverlappingRendering, hasOverlappingRendering,
@@ -792,6 +799,8 @@ static const JNINativeMethod gMethods[] = {
 
         {"nSetAlpha", "(JF)Z", (void*)android_view_RenderNode_setAlpha},
         {"nSetRenderEffect", "(JJ)Z", (void*)android_view_RenderNode_setRenderEffect},
+        {"nSetBackdropRenderEffect", "(JJ)Z",
+         (void*)android_view_RenderNode_setBackdropRenderEffect},
         {"nSetHasOverlappingRendering", "(JZ)Z",
          (void*)android_view_RenderNode_setHasOverlappingRendering},
         {"nSetUsageHint", "(JI)V", (void*)android_view_RenderNode_setUsageHint},
diff --git a/libs/hwui/pipeline/skia/BackdropFilterDrawable.cpp b/libs/hwui/pipeline/skia/BackdropFilterDrawable.cpp
new file mode 100644
index 000000000000..ffad69993fd8
--- /dev/null
+++ b/libs/hwui/pipeline/skia/BackdropFilterDrawable.cpp
@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2022 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.
+ */
+
+#include "BackdropFilterDrawable.h"
+
+#include <SkImage.h>
+#include <SkSurface.h>
+
+#include "RenderNode.h"
+#include "RenderNodeDrawable.h"
+
+namespace android {
+namespace uirenderer {
+namespace skiapipeline {
+
+BackdropFilterDrawable::~BackdropFilterDrawable() {}
+
+bool BackdropFilterDrawable::prepareToDraw(SkCanvas* canvas, const RenderProperties& properties,
+                                           int backdropImageWidth, int backdropImageHeight) {
+    // the drawing bounds for blurred content.
+    mDstBounds.setWH(properties.getWidth(), properties.getHeight());
+
+    float alphaMultiplier = 1.0f;
+    RenderNodeDrawable::setViewProperties(properties, canvas, &alphaMultiplier, true);
+
+    // get proper subset for previous content.
+    canvas->getTotalMatrix().mapRect(&mImageSubset, mDstBounds);
+    SkRect imageSubset(mImageSubset);
+    // ensure the subset is inside bounds of previous content.
+    if (!mImageSubset.intersect(SkRect::MakeWH(backdropImageWidth, backdropImageHeight))) {
+        return false;
+    }
+
+    // correct the drawing bounds if subset was changed.
+    if (mImageSubset != imageSubset) {
+        SkMatrix inverse;
+        if (canvas->getTotalMatrix().invert(&inverse)) {
+            inverse.mapRect(&mDstBounds, mImageSubset);
+        }
+    }
+
+    // follow the alpha from the target RenderNode.
+    mPaint.setAlpha(properties.layerProperties().alpha() * alphaMultiplier);
+    return true;
+}
+
+void BackdropFilterDrawable::onDraw(SkCanvas* canvas) {
+    const RenderProperties& properties = mTargetRenderNode->properties();
+    auto* backdropFilter = properties.layerProperties().getBackdropImageFilter();
+    auto* surface = canvas->getSurface();
+    if (!backdropFilter || !surface) {
+        return;
+    }
+
+    auto backdropImage = surface->makeImageSnapshot();
+    // sync necessary properties from target RenderNode.
+    if (!prepareToDraw(canvas, properties, backdropImage->width(), backdropImage->height())) {
+        return;
+    }
+
+    auto imageSubset = mImageSubset.roundOut();
+    backdropImage =
+            backdropImage->makeWithFilter(canvas->recordingContext(), backdropFilter, imageSubset,
+                                          imageSubset, &mOutSubset, &mOutOffset);
+    canvas->drawImageRect(backdropImage, SkRect::Make(mOutSubset), mDstBounds,
+                          SkSamplingOptions(SkFilterMode::kLinear), &mPaint,
+                          SkCanvas::kStrict_SrcRectConstraint);
+}
+
+}  // namespace skiapipeline
+}  // namespace uirenderer
+}  // namespace android
diff --git a/libs/hwui/pipeline/skia/BackdropFilterDrawable.h b/libs/hwui/pipeline/skia/BackdropFilterDrawable.h
new file mode 100644
index 000000000000..9e35837675ae
--- /dev/null
+++ b/libs/hwui/pipeline/skia/BackdropFilterDrawable.h
@@ -0,0 +1,67 @@
+/*
+ * Copyright (C) 2022 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.
+ */
+
+#pragma once
+
+#include <SkCanvas.h>
+#include <SkDrawable.h>
+#include <SkPaint.h>
+
+namespace android {
+namespace uirenderer {
+
+class RenderNode;
+class RenderProperties;
+
+namespace skiapipeline {
+
+/**
+ * This drawable captures it's backdrop content and render it with a
+ * image filter.
+ */
+class BackdropFilterDrawable : public SkDrawable {
+public:
+    BackdropFilterDrawable(RenderNode* renderNode, SkCanvas* canvas)
+            : mTargetRenderNode(renderNode), mBounds(canvas->getLocalClipBounds()) {}
+
+    ~BackdropFilterDrawable();
+
+private:
+    RenderNode* mTargetRenderNode;
+    SkPaint mPaint;
+
+    SkRect mDstBounds;
+    SkRect mImageSubset;
+    SkIRect mOutSubset;
+    SkIPoint mOutOffset;
+
+    /**
+     * Check all necessary properties before actual drawing.
+     * Return true if ready to draw.
+     */
+    bool prepareToDraw(SkCanvas* canvas, const RenderProperties& properties, int backdropImageWidth,
+                       int backdropImageHeight);
+
+protected:
+    void onDraw(SkCanvas* canvas) override;
+
+    virtual SkRect onGetBounds() override { return mBounds; }
+    const SkRect mBounds;
+};
+
+}  // namespace skiapipeline
+}  // namespace uirenderer
+}  // namespace android
diff --git a/libs/hwui/pipeline/skia/RenderNodeDrawable.cpp b/libs/hwui/pipeline/skia/RenderNodeDrawable.cpp
index da4f66d45a70..9d72c2315198 100644
--- a/libs/hwui/pipeline/skia/RenderNodeDrawable.cpp
+++ b/libs/hwui/pipeline/skia/RenderNodeDrawable.cpp
@@ -362,7 +362,7 @@ void RenderNodeDrawable::drawContent(SkCanvas* canvas) const {
 }
 
 void RenderNodeDrawable::setViewProperties(const RenderProperties& properties, SkCanvas* canvas,
-                                           float* alphaMultiplier) {
+                                           float* alphaMultiplier, bool ignoreLayer) {
     if (properties.getLeft() != 0 || properties.getTop() != 0) {
         canvas->translate(properties.getLeft(), properties.getTop());
     }
@@ -378,7 +378,8 @@ void RenderNodeDrawable::setViewProperties(const RenderProperties& properties, S
             canvas->concat(*properties.getTransformMatrix());
         }
     }
-    if (Properties::getStretchEffectBehavior() == StretchEffectBehavior::UniformScale) {
+    if (Properties::getStretchEffectBehavior() == StretchEffectBehavior::UniformScale &&
+        !ignoreLayer) {
         const StretchEffect& stretch = properties.layerProperties().getStretchEffect();
         if (!stretch.isEmpty()) {
             canvas->concat(
@@ -388,10 +389,10 @@ void RenderNodeDrawable::setViewProperties(const RenderProperties& properties, S
     const bool isLayer = properties.effectiveLayerType() != LayerType::None;
     int clipFlags = properties.getClippingFlags();
     if (properties.getAlpha() < 1) {
-        if (isLayer) {
+        if (isLayer && !ignoreLayer) {
             clipFlags &= ~CLIP_TO_BOUNDS;  // bounds clipping done by layer
         }
-        if (CC_LIKELY(isLayer || !properties.getHasOverlappingRendering())) {
+        if (CC_LIKELY(isLayer || !properties.getHasOverlappingRendering()) || ignoreLayer) {
             *alphaMultiplier = properties.getAlpha();
         } else {
             // savelayer needed to create an offscreen buffer
diff --git a/libs/hwui/pipeline/skia/RenderNodeDrawable.h b/libs/hwui/pipeline/skia/RenderNodeDrawable.h
index c7582e734009..818ac45bf346 100644
--- a/libs/hwui/pipeline/skia/RenderNodeDrawable.h
+++ b/libs/hwui/pipeline/skia/RenderNodeDrawable.h
@@ -120,7 +120,7 @@ private:
      * Applies the rendering properties of a view onto a SkCanvas.
      */
     static void setViewProperties(const RenderProperties& properties, SkCanvas* canvas,
-                                  float* alphaMultiplier);
+                                  float* alphaMultiplier, bool ignoreLayer = false);
 
     /**
      * Stores transform on the canvas at time of recording and is used for
@@ -149,6 +149,11 @@ private:
      * display list that is searched for any render nodes with getProjectBackwards==true
      */
     SkiaDisplayList* mProjectedDisplayList = nullptr;
+
+    /**
+     * Allow BackdropFilterDrawable to apply same render properties onto SkCanvas.
+     */
+    friend class BackdropFilterDrawable;
 };
 
 }  // namespace skiapipeline
diff --git a/libs/hwui/pipeline/skia/SkiaRecordingCanvas.cpp b/libs/hwui/pipeline/skia/SkiaRecordingCanvas.cpp
index 3ca7eeb37a89..58c14c1fabbd 100644
--- a/libs/hwui/pipeline/skia/SkiaRecordingCanvas.cpp
+++ b/libs/hwui/pipeline/skia/SkiaRecordingCanvas.cpp
@@ -37,6 +37,7 @@
 #include "NinePatchUtils.h"
 #include "RenderNode.h"
 #include "pipeline/skia/AnimatedDrawables.h"
+#include "pipeline/skia/BackdropFilterDrawable.h"
 #ifdef __ANDROID__ // Layoutlib does not support GL, Vulcan etc.
 #include "pipeline/skia/GLFunctorDrawable.h"
 #include "pipeline/skia/VkFunctorDrawable.h"
@@ -168,6 +169,14 @@ void SkiaRecordingCanvas::drawRenderNode(uirenderer::RenderNode* renderNode) {
         // Put Vulkan WebViews with non-rectangular clips in a HW layer
         renderNode->mutateStagingProperties().setClipMayBeComplex(mRecorder.isClipMayBeComplex());
     }
+
+    // draw backdrop filter drawable if needed.
+    if (renderNode->stagingProperties().layerProperties().getBackdropImageFilter()) {
+        auto* backdropFilterDrawable =
+                mDisplayList->allocateDrawable<BackdropFilterDrawable>(renderNode, asSkCanvas());
+        drawDrawable(backdropFilterDrawable);
+    }
+
     drawDrawable(&renderNodeDrawable);
 
     // use staging property, since recording on UI thread
diff --git a/libs/hwui/tests/unit/RenderNodeDrawableTests.cpp b/libs/hwui/tests/unit/RenderNodeDrawableTests.cpp
index 596bd37e4cf5..f67042b21f8f 100644
--- a/libs/hwui/tests/unit/RenderNodeDrawableTests.cpp
+++ b/libs/hwui/tests/unit/RenderNodeDrawableTests.cpp
@@ -20,14 +20,17 @@
 #include <SkBlendMode.h>
 #include <SkClipStack.h>
 #include <SkSurface_Base.h>
+#include <include/effects/SkImageFilters.h>
 #include <string.h>
+
 #include "AnimationContext.h"
 #include "DamageAccumulator.h"
 #include "FatalTestCanvas.h"
 #include "IContextFactory.h"
-#include "hwui/Paint.h"
 #include "RecordingCanvas.h"
 #include "SkiaCanvas.h"
+#include "hwui/Paint.h"
+#include "pipeline/skia/BackdropFilterDrawable.h"
 #include "pipeline/skia/SkiaDisplayList.h"
 #include "pipeline/skia/SkiaOpenGLPipeline.h"
 #include "pipeline/skia/SkiaPipeline.h"
@@ -1210,3 +1213,77 @@ RENDERTHREAD_SKIA_PIPELINE_TEST(SkiaRecordingCanvas, drawVectorDrawable) {
     canvas.drawDrawable(&drawable);
     EXPECT_EQ(2, canvas.mDrawCounter);
 }
+
+// Verify drawing logics for BackdropFilterDrawable
+RENDERTHREAD_TEST(BackdropFilterDrawable, drawing) {
+    static const int CANVAS_WIDTH = 100;
+    static const int CANVAS_HEIGHT = 200;
+    class SimpleTestCanvas : public TestCanvasBase {
+    public:
+        SkRect mDstBounds;
+        SimpleTestCanvas() : TestCanvasBase(CANVAS_WIDTH, CANVAS_HEIGHT) {}
+        void onDrawRect(const SkRect& rect, const SkPaint& paint) override {
+            // did nothing.
+        }
+
+        // called when BackdropFilterDrawable is drawn.
+        void onDrawImageRect2(const SkImage*, const SkRect& src, const SkRect& dst,
+                              const SkSamplingOptions&, const SkPaint*,
+                              SrcRectConstraint) override {
+            mDrawCounter++;
+            mDstBounds = dst;
+        }
+    };
+    class SimpleLayer : public SkSurface_Base {
+    public:
+        SimpleLayer()
+                : SkSurface_Base(SkImageInfo::MakeN32Premul(CANVAS_WIDTH, CANVAS_HEIGHT), nullptr) {
+        }
+        virtual sk_sp<SkImage> onNewImageSnapshot(const SkIRect* bounds) override {
+            SkBitmap bitmap;
+            bitmap.allocN32Pixels(CANVAS_WIDTH, CANVAS_HEIGHT);
+            bitmap.setImmutable();
+            return SkImage::MakeFromBitmap(bitmap);
+        }
+        SkCanvas* onNewCanvas() override { return new SimpleTestCanvas(); }
+        sk_sp<SkSurface> onNewSurface(const SkImageInfo&) override { return nullptr; }
+        bool onCopyOnWrite(ContentChangeMode) override { return true; }
+        void onWritePixels(const SkPixmap&, int x, int y) {}
+    };
+
+    auto node = TestUtils::createSkiaNode(0, 0, CANVAS_WIDTH, CANVAS_HEIGHT,
+                                          [](RenderProperties& props, SkiaRecordingCanvas& canvas) {
+                                              canvas.drawRect(0, 0, CANVAS_WIDTH, CANVAS_HEIGHT,
+                                                              Paint());
+                                          });
+
+    sk_sp<SkSurface> surface(new SimpleLayer());
+    auto* canvas = reinterpret_cast<SimpleTestCanvas*>(surface->getCanvas());
+    RenderNodeDrawable drawable(node.get(), canvas, true);
+    BackdropFilterDrawable backdropDrawable(node.get(), canvas);
+    canvas->drawDrawable(&drawable);
+    canvas->drawDrawable(&backdropDrawable);
+    // no backdrop filter, skip drawing.
+    EXPECT_EQ(0, canvas->mDrawCounter);
+
+    sk_sp<SkImageFilter> filter(SkImageFilters::Blur(3, 3, nullptr));
+    node->animatorProperties().mutateLayerProperties().setBackdropImageFilter(filter.get());
+    canvas->drawDrawable(&drawable);
+    canvas->drawDrawable(&backdropDrawable);
+    // backdrop filter is set, ok to draw.
+    EXPECT_EQ(1, canvas->mDrawCounter);
+    EXPECT_EQ(SkRect::MakeLTRB(0, 0, CANVAS_WIDTH, CANVAS_HEIGHT), canvas->mDstBounds);
+
+    canvas->translate(30, 30);
+    canvas->drawDrawable(&drawable);
+    canvas->drawDrawable(&backdropDrawable);
+    // the drawable is still visible, ok to draw.
+    EXPECT_EQ(2, canvas->mDrawCounter);
+    EXPECT_EQ(SkRect::MakeLTRB(0, 0, CANVAS_WIDTH - 30, CANVAS_HEIGHT - 30), canvas->mDstBounds);
+
+    canvas->translate(CANVAS_WIDTH, CANVAS_HEIGHT);
+    canvas->drawDrawable(&drawable);
+    canvas->drawDrawable(&backdropDrawable);
+    // the drawable is invisible, skip drawing.
+    EXPECT_EQ(2, canvas->mDrawCounter);
+}