add scaledimagecache

bench/ImageCacheBench.cpp

+/*
+ * Copyright 2013 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkBenchmark.h"
+#include "SkScaledImageCache.h"
+
+class ImageCacheBench : public SkBenchmark {
+    SkScaledImageCache  fCache;
+    SkBitmap            fBM;
+
+    enum {
+        N = SkBENCHLOOP(1000),
+        DIM = 1,
+        CACHE_COUNT = 500
+    };
+public:
+    ImageCacheBench(void* param) : INHERITED(param) , fCache(CACHE_COUNT * 100) {
+        fBM.setConfig(SkBitmap::kARGB_8888_Config, DIM, DIM);
+        fBM.allocPixels();
+    }
+
+    void populateCache() {
+        SkScalar scale = 1;
+        for (int i = 0; i < CACHE_COUNT; ++i) {
+            SkBitmap tmp;
+            tmp.setConfig(SkBitmap::kARGB_8888_Config, 1, 1);
+            tmp.allocPixels();
+            fCache.unlock(fCache.addAndLock(fBM, scale, scale, tmp));
+            scale += 1;
+        }
+    }
+
+protected:
+    virtual const char* onGetName() SK_OVERRIDE {
+        return "imagecache";
+    }
+
+    virtual void onDraw(SkCanvas*) SK_OVERRIDE {
+        if (fCache.getBytesUsed() == 0) {
+            this->populateCache();
+        }
+
+        SkBitmap tmp;
+        // search for a miss (-1 scale)
+        for (int i = 0; i < N; ++i) {
+            (void)fCache.findAndLock(fBM, -1, -1, &tmp);
+        }
+    }
+
+private:
+    typedef SkBenchmark INHERITED;
+};
+
+///////////////////////////////////////////////////////////////////////////////
+
+DEF_BENCH( return new ImageCacheBench(p); )