Adding color cube to fuzzer

samplecode/SampleFilterFuzz.cpp

Index: samplecode/SampleFilterFuzz.cpp
diff --git a/samplecode/SampleFilterFuzz.cpp b/samplecode/SampleFilterFuzz.cpp
index e073f80b0c1c16651cd2eb47d2dc0ce6aadc6582..a01c38b05e3f09b6fd91f924da3267f6150d7fd8 100644
--- a/samplecode/SampleFilterFuzz.cpp
+++ b/samplecode/SampleFilterFuzz.cpp
@@ -9,6 +9,7 @@
 #include "SkBitmapSource.h"
 #include "SkBlurImageFilter.h"
 #include "SkCanvas.h"
+#include "SkColorCubeFilter.h"
 #include "SkColorFilter.h"
 #include "SkColorFilterImageFilter.h"
 #include "SkComposeImageFilter.h"
@@ -210,6 +211,48 @@ static const SkBitmap& make_bitmap() {
     return bitmap[R(2)];
 }
 
+static SkData* make_3Dlut(int* cubeDimension, bool invR, bool invG, bool invB) {
+    int size = 4;
+    switch (R(5)) {

[Stephen White, 2014/10/24 22:48:37]

Nit: couldn't this also be

int size = 4 << R(5) ?

[sugoi1, 2014/10/27 14:55:32]

Done.

+    case 4:
+        size *= 2; // 64
+    case 3:
+        size *= 2; // 32
+    case 2:
+        size *= 2; // 16
+    case 1:
+        size *= 2; // 8
+    default:
+        break;
+    }
+
+    SkData* data = SkData::NewUninitialized(sizeof(SkColor) * size * size * size);

[Stephen White, 2014/10/24 22:48:38]

Should we also be trying to give the fuzzer truncated buffers (ie., buffer <
size^3 in memory)? Or will the fuzzer hit that case automatically?

[sugoi1, 2014/10/27 14:55:32]

Yeah, the fuzzer should take care of that case automatically.

+    SkColor* pixels = (SkColor*)(data->writable_data());
+    SkAutoMalloc lutMemory(size);
+    SkAutoMalloc invLutMemory(size);
+    uint8_t* lut = (uint8_t*)lutMemory.get();
+    uint8_t* invLut = (uint8_t*)invLutMemory.get();
+    const int maxIndex = size - 1;
+    for (int i = 0; i < size; i++) {
+        lut[i] = (i * 255) / maxIndex;
+        invLut[i] = ((maxIndex - i) * 255) / maxIndex;
+    }
+    for (int r = 0; r < size; ++r) {
+        for (int g = 0; g < size; ++g) {
+            for (int b = 0; b < size; ++b) {
+                pixels[(size * ((size * b) + g)) + r] = SkColorSetARGB(0xFF,
+                        invR ? invLut[r] : lut[r],
+                        invG ? invLut[g] : lut[g],
+                        invB ? invLut[b] : lut[b]);
+            }
+        }
+    }
+    if (cubeDimension) {
+        *cubeDimension = size;
+    }
+    return data;
+}
+
 static void drawSomething(SkCanvas* canvas) {
     SkPaint paint;
 
@@ -238,7 +281,7 @@ static SkImageFilter* make_image_filter(bool canBeNull = true) {
     // Add a 1 in 3 chance to get a NULL input
     if (canBeNull && (R(3) == 1)) { return filter; }
 
-    enum { ALPHA_THRESHOLD, MERGE, COLOR, BLUR, MAGNIFIER,
+    enum { ALPHA_THRESHOLD, MERGE, COLOR, LUT3D, BLUR, MAGNIFIER,
            DOWN_SAMPLE, XFERMODE, OFFSET, MATRIX, MATRIX_CONVOLUTION, COMPOSE,
            DISTANT_LIGHT, POINT_LIGHT, SPOT_LIGHT, NOISE, DROP_SHADOW,
            MORPHOLOGY, BITMAP, DISPLACE, TILE, PICTURE, NUM_FILTERS };
@@ -258,6 +301,14 @@ static SkImageFilter* make_image_filter(bool canBeNull = true) {
         filter = cf.get() ? SkColorFilterImageFilter::Create(cf, make_image_filter()) : 0;
     }
         break;
+    case LUT3D:
+    {
+        int cubeDimension;
+        SkAutoDataUnref lut3D(make_3Dlut(&cubeDimension, (R(2) == 1), (R(2) == 1), (R(2) == 1)));
+        SkAutoTUnref<SkColorFilter> cf(SkColorCubeFilter::Create(lut3D, cubeDimension));
+        filter = cf.get() ? SkColorFilterImageFilter::Create(cf, make_image_filter()) : 0;
+    }
+        break;
     case BLUR:
         filter = SkBlurImageFilter::Create(make_scalar(true), make_scalar(true), make_image_filter());
         break;