Add ShadowShaderAnimation benchmark DO NOT MERGE

Bug: 34809371
Test: manual

New benchmark uses several levels of overdraw from just shadows to benchmark
shadow shader performance.

Tessellation workload is minimal, due to simple rect caster shape.

Change-Id: I572476bd54e04566851f39027ada7254597b37f8

libs/hwui/tests/common/scenes/ShadowShaderAnimation.cpp

@@ -0,0 +1,68 @@
+/*
+ * Copyright (C) 2017 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 "TestSceneBase.h"
+
+class ShadowShaderAnimation;
+
+static TestScene::Registrar _ShadowShader(TestScene::Info{
+    "shadowshader",
+    "A set of overlapping shadowed areas with simple tessellation useful for"
+    " benchmarking shadow shader performance.",
+    TestScene::simpleCreateScene<ShadowShaderAnimation>
+});
+
+class ShadowShaderAnimation : public TestScene {
+public:
+    std::vector< sp<RenderNode> > cards;
+    void createContent(int width, int height, TestCanvas& canvas) override {
+        canvas.drawColor(0xFFFFFFFF, SkXfermode::kSrcOver_Mode);
+        canvas.insertReorderBarrier(true);
+
+        int outset = 50;
+        for (int i = 0; i < 10; i++) {
+            sp<RenderNode> card = createCard(outset, outset,
+                    width - (outset * 2), height - (outset * 2));
+            canvas.drawRenderNode(card.get());
+            cards.push_back(card);
+        }
+
+        canvas.insertReorderBarrier(false);
+    }
+    void doFrame(int frameNr) override {
+        int curFrame = frameNr % 10;
+        for (size_t ci = 0; ci < cards.size(); ci++) {
+            cards[ci]->mutateStagingProperties().setTranslationX(curFrame);
+            cards[ci]->mutateStagingProperties().setTranslationY(curFrame);
+            cards[ci]->setPropertyFieldsDirty(RenderNode::X | RenderNode::Y);
+        }
+    }
+private:
+    sp<RenderNode> createCard(int x, int y, int width, int height) {
+        return TestUtils::createNode(x, y, x + width, y + height,
+                [width, height](RenderProperties& props, TestCanvas& canvas) {
+            props.setElevation(1000);
+
+            // Set 0 radius, no clipping, so shadow is easy to compute. Slightly transparent outline
+            // to signal contents aren't opaque (not necessary though, as elevation is so high, no
+            // inner content to cut out)
+            props.mutableOutline().setRoundRect(0, 0, width, height, 0, 0.99f);
+            props.mutableOutline().setShouldClip(false);
+
+            // don't draw anything to card's canvas - we just want the shadow
+        });
+    }
+};