Adding 3D lut color filter

bench/ColorProfileBench.cpp

+/*
+ * Copyright 2014 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 "SkCanvas.h"
+#include "SkColorProfileFilter.h"
+
+class ColorProfileBench : public Benchmark {
+    SkISize fSize;
+    bool fInitialized;

[bsalomon, 2014/10/03 19:45:00]

Trivial, but this is the same as SkToBool(fCubeData)

[sugoi1, 2014/10/06 15:04:54]

Done.

+    int fCubeDimension;
+    SkData* fCubeData;
+
+public:
+    ColorProfileBench()
+     : fInitialized(false)
+     , fCubeDimension(0)
+     , fCubeData(NULL) {
+        fSize = SkISize::Make(1024, 768);

[Stephen White, 2014/10/03 19:40:49]

Maybe we should make this 2Kx1.5K, to be closer to what people will see in a
full-screen photo viewer.

[sugoi1, 2014/10/06 15:04:54]

Done. Changed it to 2880x1800 (Curent MacBook Pro resolution).

+    }
+
+    ~ColorProfileBench() {
+        SkSafeUnref(fCubeData);
+    }
+
+protected:
+    virtual const char* onGetName() SK_OVERRIDE {
+        return "colorprofile";
+    }
+
+    virtual void onPreDraw() SK_OVERRIDE {
+        if (!fInitialized) {
+            this->makeCubeData();
+            fInitialized = true;
+        }
+    }
+
+    virtual void onDraw(const int loops, SkCanvas* canvas) SK_OVERRIDE {
+        this->test(loops, canvas, 0, 0);
+    }
+
+private:
+    void makeCubeData() {
+        fCubeDimension = 32;
+        fCubeData = SkData::NewUninitialized(sizeof(SkColor) *
+            fCubeDimension * fCubeDimension * fCubeDimension);
+        SkColor* pixels = (SkColor*)(fCubeData->writable_data());
+        SkAutoMalloc lutMemory(fCubeDimension);
+        uint8_t* lut = (uint8_t*)lutMemory.get();
+        const int maxIndex = fCubeDimension - 1;
+        for (int i = 0; i < fCubeDimension; ++i) {
+            // Make an invert lut, but the content of
+            // the lut shouldn't affect performance.
+            lut[i] = ((maxIndex - i) * 255) / maxIndex;
+        }
+        for (int r = 0; r < fCubeDimension; ++r) {
+            for (int g = 0; g < fCubeDimension; ++g) {
+                for (int b = 0; b < fCubeDimension; ++b) {
+                    pixels[(fCubeDimension * ((fCubeDimension * b) + g)) + r] =
+                        SkColorSetARGB(0xFF, lut[r], lut[g], lut[b]);
+                }
+            }
+        }
+    }
+
+    void drawClippedRect(SkCanvas* canvas, int x, int y, const SkPaint& paint) {
+        canvas->save();
+        canvas->clipRect(SkRect::MakeXYWH(SkIntToScalar(x), SkIntToScalar(y),

[Stephen White, 2014/10/03 19:40:49]

Now that we have a bench, could you try it without this clipRect? If there's no
delta, we can remove it. (It was mostly necessary for SkImageFilters, when they
were too dumb to optimize their intermediate buffers.)

[sugoi1, 2014/10/06 15:04:54]

Done.

+                         SkIntToScalar(fSize.width()), SkIntToScalar(fSize.height())));
+        SkRect r = SkRect::MakeXYWH(SkIntToScalar(x), SkIntToScalar(y),
+                                    SkIntToScalar(fSize.width()),
+                                    SkIntToScalar(fSize.height()));
+        canvas->drawRect(r, paint);
+        canvas->restore();
+    }
+
+    void test(const int loops, SkCanvas* canvas, int x, int y) {
+        SkAutoTUnref<SkColorFilter> colorProfile(
+            SkColorProfileFilter::Create(fCubeData, fCubeDimension));
+        SkPaint paint;
+        paint.setColorFilter(colorProfile);

[Stephen White, 2014/10/03 19:40:49]

Presumably, the paint color will default to black (or white? I can't remember).
Either way, won't this only be accessing a single element of the cube? IWBN to
make sure that we exercise the whole cube (or at least, a good part of it).
Maybe we should fill it with a gradient (as in your GM) or random pixels.

[sugoi1, 2014/10/06 15:04:54]

Done.

+
+        for (int i = 0; i < loops; i++) {
+            this->drawClippedRect(canvas, x, y, paint);
+        }
+    }
+
+    typedef Benchmark INHERITED;
+};
+
+///////////////////////////////////////////////////////////////////////////////
+
+DEF_BENCH( return new ColorProfileBench(); )