Custom looper code for Android

Test: make

Bug: 178700363
Change-Id: I1d328275ab5e0c9b6b9171ef075f71274e50a3f5
diff --git a/libs/hwui/Android.bp b/libs/hwui/Android.bp
index f481228..0704750 100644
--- a/libs/hwui/Android.bp
+++ b/libs/hwui/Android.bp
@@ -444,6 +444,7 @@
         "renderthread/TimeLord.cpp",
         "hwui/AnimatedImageDrawable.cpp",
         "hwui/Bitmap.cpp",
+        "hwui/BlurDrawLooper.cpp",
         "hwui/Canvas.cpp",
         "hwui/ImageDecoder.cpp",
         "hwui/MinikinSkia.cpp",
diff --git a/libs/hwui/SkiaCanvas.cpp b/libs/hwui/SkiaCanvas.cpp
index 8fddf71..1fddac4 100644
--- a/libs/hwui/SkiaCanvas.cpp
+++ b/libs/hwui/SkiaCanvas.cpp
@@ -463,9 +463,7 @@
 }
 
 void SkiaCanvas::drawPoint(float x, float y, const Paint& paint) {
-    apply_looper(&paint, [&](const SkPaint& p) {
-        mCanvas->drawPoint(x, y, p);
-    });
+    apply_looper(&paint, [&](const SkPaint& p) { mCanvas->drawPoint(x, y, p); });
 }
 
 void SkiaCanvas::drawPoints(const float* points, int count, const Paint& paint) {
@@ -493,9 +491,7 @@
 
 void SkiaCanvas::drawRegion(const SkRegion& region, const Paint& paint) {
     if (CC_UNLIKELY(paint.nothingToDraw())) return;
-    apply_looper(&paint, [&](const SkPaint& p) {
-        mCanvas->drawRegion(region, p);
-    });
+    apply_looper(&paint, [&](const SkPaint& p) { mCanvas->drawRegion(region, p); });
 }
 
 void SkiaCanvas::drawRoundRect(float left, float top, float right, float bottom, float rx, float ry,
@@ -509,24 +505,18 @@
 
 void SkiaCanvas::drawDoubleRoundRect(const SkRRect& outer, const SkRRect& inner,
                                 const Paint& paint) {
-    apply_looper(&paint, [&](const SkPaint& p) {
-        mCanvas->drawDRRect(outer, inner, p);
-    });
+    apply_looper(&paint, [&](const SkPaint& p) { mCanvas->drawDRRect(outer, inner, p); });
 }
 
 void SkiaCanvas::drawCircle(float x, float y, float radius, const Paint& paint) {
     if (CC_UNLIKELY(radius <= 0 || paint.nothingToDraw())) return;
-    apply_looper(&paint, [&](const SkPaint& p) {
-        mCanvas->drawCircle(x, y, radius, p);
-    });
+    apply_looper(&paint, [&](const SkPaint& p) { mCanvas->drawCircle(x, y, radius, p); });
 }
 
 void SkiaCanvas::drawOval(float left, float top, float right, float bottom, const Paint& paint) {
     if (CC_UNLIKELY(paint.nothingToDraw())) return;
     SkRect oval = SkRect::MakeLTRB(left, top, right, bottom);
-    apply_looper(&paint, [&](const SkPaint& p) {
-        mCanvas->drawOval(oval, p);
-    });
+    apply_looper(&paint, [&](const SkPaint& p) { mCanvas->drawOval(oval, p); });
 }
 
 void SkiaCanvas::drawArc(float left, float top, float right, float bottom, float startAngle,
@@ -547,9 +537,7 @@
     if (CC_UNLIKELY(path.isEmpty() && (!path.isInverseFillType()))) {
         return;
     }
-    apply_looper(&paint, [&](const SkPaint& p) {
-        mCanvas->drawPath(path, p);
-    });
+    apply_looper(&paint, [&](const SkPaint& p) { mCanvas->drawPath(path, p); });
 }
 
 void SkiaCanvas::drawVertices(const SkVertices* vertices, SkBlendMode mode, const Paint& paint) {
diff --git a/libs/hwui/SkiaCanvas.h b/libs/hwui/SkiaCanvas.h
index 155f6df..eac3f22 100644
--- a/libs/hwui/SkiaCanvas.h
+++ b/libs/hwui/SkiaCanvas.h
@@ -208,29 +208,21 @@
      */
     PaintCoW&& filterPaint(PaintCoW&& paint) const;
 
+    // proc(const SkPaint& modifiedPaint)
     template <typename Proc> void apply_looper(const Paint* paint, Proc proc) {
         SkPaint skp;
-        SkDrawLooper* looper = nullptr;
+        BlurDrawLooper* looper = nullptr;
         if (paint) {
             skp = *filterPaint(paint);
             looper = paint->getLooper();
         }
         if (looper) {
-            SkSTArenaAlloc<256> alloc;
-            SkDrawLooper::Context* ctx = looper->makeContext(&alloc);
-            if (ctx) {
-                SkDrawLooper::Context::Info info;
-                for (;;) {
-                    SkPaint p = skp;
-                    if (!ctx->next(&info, &p)) {
-                        break;
-                    }
-                    mCanvas->save();
-                    mCanvas->translate(info.fTranslate.fX, info.fTranslate.fY);
-                    proc(p);
-                    mCanvas->restore();
-                }
-            }
+            looper->apply(skp, [&](SkPoint offset, const SkPaint& modifiedPaint) {
+                mCanvas->save();
+                mCanvas->translate(offset.fX, offset.fY);
+                proc(modifiedPaint);
+                mCanvas->restore();
+            });
         } else {
             proc(skp);
         }
diff --git a/libs/hwui/hwui/BlurDrawLooper.cpp b/libs/hwui/hwui/BlurDrawLooper.cpp
new file mode 100644
index 0000000..27a038d
--- /dev/null
+++ b/libs/hwui/hwui/BlurDrawLooper.cpp
@@ -0,0 +1,45 @@
+/*
+ * Copyright (C) 2021 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 "BlurDrawLooper.h"
+#include <SkMaskFilter.h>
+
+namespace android {
+
+BlurDrawLooper::BlurDrawLooper(SkColor4f color, float blurSigma, SkPoint offset)
+        : mColor(color), mBlurSigma(blurSigma), mOffset(offset) {}
+
+BlurDrawLooper::~BlurDrawLooper() = default;
+
+SkPoint BlurDrawLooper::apply(SkPaint* paint) const {
+    paint->setColor(mColor);
+    if (mBlurSigma > 0) {
+        paint->setMaskFilter(SkMaskFilter::MakeBlur(kNormal_SkBlurStyle, mBlurSigma, true));
+    }
+    return mOffset;
+}
+
+sk_sp<BlurDrawLooper> BlurDrawLooper::Make(SkColor4f color, SkColorSpace* cs, float blurSigma,
+                                           SkPoint offset) {
+    if (cs) {
+        SkPaint tmp;
+        tmp.setColor(color, cs);  // converts color to sRGB
+        color = tmp.getColor4f();
+    }
+    return sk_sp<BlurDrawLooper>(new BlurDrawLooper(color, blurSigma, offset));
+}
+
+}  // namespace android
diff --git a/libs/hwui/hwui/BlurDrawLooper.h b/libs/hwui/hwui/BlurDrawLooper.h
new file mode 100644
index 0000000..7e6786f
--- /dev/null
+++ b/libs/hwui/hwui/BlurDrawLooper.h
@@ -0,0 +1,53 @@
+/*
+ * Copyright (C) 2021 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.
+ */
+
+#ifndef ANDROID_GRAPHICS_BLURDRAWLOOPER_H_
+#define ANDROID_GRAPHICS_BLURDRAWLOOPER_H_
+
+#include <SkPaint.h>
+#include <SkRefCnt.h>
+
+class SkColorSpace;
+
+namespace android {
+
+class BlurDrawLooper : public SkRefCnt {
+public:
+    static sk_sp<BlurDrawLooper> Make(SkColor4f, SkColorSpace*, float blurSigma, SkPoint offset);
+
+    ~BlurDrawLooper() override;
+
+    // proc(SkPoint offset, const SkPaint& modifiedPaint)
+    template <typename DrawProc>
+    void apply(const SkPaint& paint, DrawProc proc) const {
+        SkPaint p(paint);
+        proc(this->apply(&p), p);  // draw the shadow
+        proc({0, 0}, paint);       // draw the original (on top)
+    }
+
+private:
+    const SkColor4f mColor;
+    const float mBlurSigma;
+    const SkPoint mOffset;
+
+    SkPoint apply(SkPaint* paint) const;
+
+    BlurDrawLooper(SkColor4f, float, SkPoint);
+};
+
+}  // namespace android
+
+#endif  // ANDROID_GRAPHICS_BLURDRAWLOOPER_H_
diff --git a/libs/hwui/hwui/Paint.h b/libs/hwui/hwui/Paint.h
index 05bae5c..d9c9eee 100644
--- a/libs/hwui/hwui/Paint.h
+++ b/libs/hwui/hwui/Paint.h
@@ -17,11 +17,11 @@
 #ifndef ANDROID_GRAPHICS_PAINT_H_
 #define ANDROID_GRAPHICS_PAINT_H_
 
+#include "BlurDrawLooper.h"
 #include "Typeface.h"
 
 #include <cutils/compiler.h>
 
-#include <SkDrawLooper.h>
 #include <SkFont.h>
 #include <SkPaint.h>
 #include <string>
@@ -59,8 +59,8 @@
     SkFont& getSkFont() { return mFont; }
     const SkFont& getSkFont() const { return mFont; }
 
-    SkDrawLooper* getLooper() const { return mLooper.get(); }
-    void setLooper(sk_sp<SkDrawLooper> looper) { mLooper = std::move(looper); }
+    BlurDrawLooper* getLooper() const { return mLooper.get(); }
+    void setLooper(sk_sp<BlurDrawLooper> looper) { mLooper = std::move(looper); }
 
     // These shadow the methods on SkPaint, but we need to so we can keep related
     // attributes in-sync.
@@ -155,7 +155,7 @@
 
 private:
     SkFont mFont;
-    sk_sp<SkDrawLooper> mLooper;
+    sk_sp<BlurDrawLooper> mLooper;
 
     float mLetterSpacing = 0;
     float mWordSpacing = 0;
diff --git a/libs/hwui/jni/Paint.cpp b/libs/hwui/jni/Paint.cpp
index 3c86b28..bcec0fa 100644
--- a/libs/hwui/jni/Paint.cpp
+++ b/libs/hwui/jni/Paint.cpp
@@ -25,7 +25,6 @@
 #include <nativehelper/ScopedUtfChars.h>
 #include <nativehelper/ScopedPrimitiveArray.h>
 
-#include "SkBlurDrawLooper.h"
 #include "SkColorFilter.h"
 #include "SkFont.h"
 #include "SkFontMetrics.h"
@@ -39,6 +38,7 @@
 #include "unicode/ushape.h"
 #include "utils/Blur.h"
 
+#include <hwui/BlurDrawLooper.h>
 #include <hwui/MinikinSkia.h>
 #include <hwui/MinikinUtils.h>
 #include <hwui/Paint.h>
@@ -964,13 +964,13 @@
         }
         else {
             SkScalar sigma = android::uirenderer::Blur::convertRadiusToSigma(radius);
-            paint->setLooper(SkBlurDrawLooper::Make(color, cs.get(), sigma, dx, dy));
+            paint->setLooper(BlurDrawLooper::Make(color, cs.get(), sigma, {dx, dy}));
         }
     }
 
     static jboolean hasShadowLayer(CRITICAL_JNI_PARAMS_COMMA jlong paintHandle) {
         Paint* paint = reinterpret_cast<Paint*>(paintHandle);
-        return paint->getLooper() && paint->getLooper()->asABlurShadow(nullptr);
+        return paint->getLooper() != nullptr;
     }
 
     static jboolean equalsForTextMeasurement(CRITICAL_JNI_PARAMS_COMMA jlong lPaint, jlong rPaint) {
diff --git a/libs/hwui/pipeline/skia/SkiaRecordingCanvas.cpp b/libs/hwui/pipeline/skia/SkiaRecordingCanvas.cpp
index ee7c4d8..b288402 100644
--- a/libs/hwui/pipeline/skia/SkiaRecordingCanvas.cpp
+++ b/libs/hwui/pipeline/skia/SkiaRecordingCanvas.cpp
@@ -194,28 +194,20 @@
     return filterPaint(std::move(paint));
 }
 
-static SkDrawLooper* get_looper(const Paint* paint) {
+static BlurDrawLooper* get_looper(const Paint* paint) {
     return paint ? paint->getLooper() : nullptr;
 }
 
 template <typename Proc>
-void applyLooper(SkDrawLooper* looper, const SkPaint* paint, Proc proc) {
+void applyLooper(BlurDrawLooper* looper, const SkPaint* paint, Proc proc) {
     if (looper) {
-        SkSTArenaAlloc<256> alloc;
-        SkDrawLooper::Context* ctx = looper->makeContext(&alloc);
-        if (ctx) {
-            SkDrawLooper::Context::Info info;
-            for (;;) {
-                SkPaint p;
-                if (paint) {
-                    p = *paint;
-                }
-                if (!ctx->next(&info, &p)) {
-                    break;
-                }
-                proc(info.fTranslate.fX, info.fTranslate.fY, &p);
-            }
+        SkPaint p;
+        if (paint) {
+            p = *paint;
         }
+        looper->apply(p, [&](SkPoint offset, const SkPaint& modifiedPaint) {
+            proc(offset.fX, offset.fY, &modifiedPaint);
+        });
     } else {
         proc(0, 0, paint);
     }
diff --git a/libs/hwui/tests/unit/SkiaBehaviorTests.cpp b/libs/hwui/tests/unit/SkiaBehaviorTests.cpp
index 7951537..a1ba70a 100644
--- a/libs/hwui/tests/unit/SkiaBehaviorTests.cpp
+++ b/libs/hwui/tests/unit/SkiaBehaviorTests.cpp
@@ -16,7 +16,6 @@
 
 #include "tests/common/TestUtils.h"
 
-#include <SkBlurDrawLooper.h>
 #include <SkColorMatrixFilter.h>
 #include <SkColorSpace.h>
 #include <SkImagePriv.h>
@@ -85,15 +84,3 @@
     ASSERT_EQ(sRGB1.get(), sRGB2.get());
 }
 
-TEST(SkiaBehavior, blurDrawLooper) {
-    sk_sp<SkDrawLooper> looper = SkBlurDrawLooper::Make(SK_ColorRED, 5.0f, 3.0f, 4.0f);
-
-    SkDrawLooper::BlurShadowRec blur;
-    bool success = looper->asABlurShadow(&blur);
-    ASSERT_TRUE(success);
-
-    ASSERT_EQ(SK_ColorRED, blur.fColor);
-    ASSERT_EQ(5.0f, blur.fSigma);
-    ASSERT_EQ(3.0f, blur.fOffset.fX);
-    ASSERT_EQ(4.0f, blur.fOffset.fY);
-}
diff --git a/libs/hwui/tests/unit/SkiaCanvasTests.cpp b/libs/hwui/tests/unit/SkiaCanvasTests.cpp
index f77ca2a..dae3c94 100644
--- a/libs/hwui/tests/unit/SkiaCanvasTests.cpp
+++ b/libs/hwui/tests/unit/SkiaCanvasTests.cpp
@@ -17,7 +17,6 @@
 #include "tests/common/TestUtils.h"
 
 #include <hwui/Paint.h>
-#include <SkBlurDrawLooper.h>
 #include <SkCanvasStateUtils.h>
 #include <SkPicture.h>
 #include <SkPictureRecorder.h>
@@ -37,7 +36,7 @@
     // it is transparent to ensure that we still draw the rect since it has a looper
     paint.setColor(SK_ColorTRANSPARENT);
     // this is how view's shadow layers are implemented
-    paint.setLooper(SkBlurDrawLooper::Make(0xF0000000, 6.0f, 0, 10));
+    paint.setLooper(BlurDrawLooper::Make({0, 0, 0, 240.0f / 255}, nullptr, 6.0f, {0, 10}));
     canvas.drawRect(3, 3, 7, 7, paint);
 
     ASSERT_EQ(TestUtils::getColor(surface, 0, 0), SK_ColorWHITE);
diff --git a/libs/hwui/utils/PaintUtils.h b/libs/hwui/utils/PaintUtils.h
index e2fdf2f..09c6a4f 100644
--- a/libs/hwui/utils/PaintUtils.h
+++ b/libs/hwui/utils/PaintUtils.h
@@ -20,7 +20,6 @@
 #include <utils/Blur.h>
 
 #include <SkColorFilter.h>
-#include <SkDrawLooper.h>
 #include <SkPaint.h>
 #include <SkShader.h>