Add new bench to compare drawSprite() and drawBitmap().

bench/ImageFilterSpriteVsBitmap.cpp

+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "Benchmark.h"
+#include "SkOffsetImageFilter.h"
+#include "SkGradientShader.h"
+#include "SkCanvas.h"
+
+static const int kWidth = 2048, kHeight = 2048;
+
+class ImageFilterSpriteVsBitmapBench : public Benchmark {
+public:
+    ImageFilterSpriteVsBitmapBench(bool useSprite) : fUseSprite(useSprite), fInitialized(false) {}
+
+protected:
+    const char* onGetName() override {
+        if (fUseSprite) {
+            return "image_filter_drawsprite";
+        } else {
+            return "image_filter_drawbitmap";
+        }
+    }
+
+    SkIPoint onGetSize() override {
+        return SkIPoint::Make(kWidth, kHeight);
+    }
+
+    void init() {
+        fBitmap.allocN32Pixels(kWidth, kHeight);
+        fBitmap.eraseColor(SK_ColorTRANSPARENT);
+
+        SkCanvas canvas(fBitmap);
+        SkPaint paint;
+        SkPoint pts[] = { {0, 0}, {SkIntToScalar(kWidth), SkIntToScalar(kHeight)} };
+        SkColor colors[] = {
+            SK_ColorBLACK, SK_ColorGREEN, SK_ColorCYAN,
+            SK_ColorRED, 0, SK_ColorBLUE, SK_ColorWHITE
+        };
+        SkAutoTUnref<SkShader> shader(SkGradientShader::CreateLinear(
+                    pts, colors, nullptr, SK_ARRAY_COUNT(colors), SkShader::kClamp_TileMode
+        ));
+        paint.setShader(shader);
+        canvas.drawPaint(paint);
+    }
+
+    void onDraw(int loops, SkCanvas* canvas) override {
+        if (!fInitialized) {
+            init();
+            fInitialized = true;
+        }
+        SkAutoTUnref<SkImageFilter> filter(SkOffsetImageFilter::Create(SK_Scalar1, SK_Scalar1));
+        SkPaint paint;
+        paint.setImageFilter(filter);
+        canvas->clipRect(SkRect::Make(fBitmap.bounds()));
+        for (int j = 0; j < loops; j++) {
+            if (fUseSprite) {
+                canvas->drawSprite(fBitmap, 0, 0, &paint);
+            } else {
+                canvas->drawBitmap(fBitmap, 0, 0, &paint);
+            }
+        }
+    }
+
+private:
+    typedef Benchmark INHERITED;
+    SkBitmap fBitmap;
+    bool fUseSprite;
+    bool fInitialized;
+};
+
+DEF_BENCH(return new ImageFilterSpriteVsBitmapBench(true);)
+DEF_BENCH(return new ImageFilterSpriteVsBitmapBench(false);)