tests/PictureTest.cpp - platform/external/skia - Gitiles

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #include "Test.h"
 #include "SkCanvas.h"
 #include "SkColorPriv.h"
 #include "SkData.h"
 #include "SkError.h"
 #include "SkPaint.h"
 #include "SkPicture.h"
 #include "SkRandom.h"
 #include "SkRRect.h"
 #include "SkShader.h"
 #include "SkStream.h"

 #include "SkPictureUtils.h"

 static void make_bm(SkBitmap* bm, int w, int h, SkColor color, bool immutable) {
     bm->setConfig(SkBitmap::kARGB_8888_Config, w, h);
     bm->allocPixels();
     bm->eraseColor(color);
     if (immutable) {
         bm->setImmutable();
     }
 }

 typedef void (*DrawBitmapProc)(SkCanvas*, const SkBitmap&, const SkPoint&);

 static void drawbitmap_proc(SkCanvas* canvas, const SkBitmap& bm,
                             const SkPoint& pos) {
     canvas->drawBitmap(bm, pos.fX, pos.fY, NULL);
 }

 static void drawbitmaprect_proc(SkCanvas* canvas, const SkBitmap& bm,
                                 const SkPoint& pos) {
     SkRect r = {
         0, 0, SkIntToScalar(bm.width()), SkIntToScalar(bm.height())
     };
     r.offset(pos.fX, pos.fY);
     canvas->drawBitmapRectToRect(bm, NULL, r, NULL);
 }

 static void drawshader_proc(SkCanvas* canvas, const SkBitmap& bm,
                             const SkPoint& pos) {
     SkRect r = {
         0, 0, SkIntToScalar(bm.width()), SkIntToScalar(bm.height())
     };
     r.offset(pos.fX, pos.fY);

     SkShader* s = SkShader::CreateBitmapShader(bm,
                                                SkShader::kClamp_TileMode,
                                                SkShader::kClamp_TileMode);
     SkPaint paint;
     paint.setShader(s)->unref();
     canvas->drawRect(r, paint);
     canvas->drawOval(r, paint);
     SkRRect rr;
     rr.setRectXY(r, 10, 10);
     canvas->drawRRect(rr, paint);
 }

 // Return a picture with the bitmaps drawn at the specified positions.
 static SkPicture* record_bitmaps(const SkBitmap bm[], const SkPoint pos[],
                                  int count, DrawBitmapProc proc) {
     SkPicture* pic = new SkPicture;
     SkCanvas* canvas = pic->beginRecording(1000, 1000);
     for (int i = 0; i < count; ++i) {
         proc(canvas, bm[i], pos[i]);
     }
     pic->endRecording();
     return pic;
 }

 static void rand_rect(SkRect* rect, SkMWCRandom& rand, SkScalar W, SkScalar H) {
     rect->fLeft   = rand.nextRangeScalar(-W, 2*W);
     rect->fTop    = rand.nextRangeScalar(-H, 2*H);
     rect->fRight  = rect->fLeft + rand.nextRangeScalar(0, W);
     rect->fBottom = rect->fTop + rand.nextRangeScalar(0, H);

     // we integralize rect to make our tests more predictable, since Gather is
     // a little sloppy.
     SkIRect ir;
     rect->round(&ir);
     rect->set(ir);
 }

 // Allocate result to be large enough to hold subset, and then draw the picture
 // into it, offsetting by subset's top/left corner.
 static void draw(SkPicture* pic, const SkRect& subset, SkBitmap* result) {
     SkIRect ir;
     subset.roundOut(&ir);
     int w = ir.width();
     int h = ir.height();
     make_bm(result, w, h, 0, false);

     SkCanvas canvas(*result);
     canvas.translate(-SkIntToScalar(ir.left()), -SkIntToScalar(ir.top()));
     canvas.drawPicture(*pic);
 }

 template <typename T> int find_index(const T* array, T elem, int count) {
     for (int i = 0; i < count; ++i) {
         if (array[i] == elem) {
             return i;
         }
     }
     return -1;
 }

 // Return true if 'ref' is found in array[]
 static bool find(SkPixelRef const * const * array, SkPixelRef const * ref, int count) {
     return find_index<const SkPixelRef*>(array, ref, count) >= 0;
 }

 // Look at each pixel in bm, and if its color appears in colors[], find the
 // corresponding value in refs[] and append that ref into array, skipping
 // duplicates of the same value.
 static void gather_from_colors(const SkBitmap& bm, SkPixelRef* const refs[],
                                int count, SkTDArray<SkPixelRef*>* array) {
     // Since we only want to return unique values in array, when we scan we just
     // set a bit for each index'd color found. In practice we only have a few
     // distinct colors, so we just use an int's bits as our array. Hence the
     // assert that count <= number-of-bits-in-our-int.
     SkASSERT((unsigned)count <= 32);
     uint32_t bitarray = 0;

     SkAutoLockPixels alp(bm);

     for (int y = 0; y < bm.height(); ++y) {
         for (int x = 0; x < bm.width(); ++x) {
             SkPMColor pmc = *bm.getAddr32(x, y);
             // the only good case where the color is not found would be if
             // the color is transparent, meaning no bitmap was drawn in that
             // pixel.
             if (pmc) {
                 uint32_t index = SkGetPackedR32(pmc);
                 SkASSERT(SkGetPackedG32(pmc) == index);
                 SkASSERT(SkGetPackedB32(pmc) == index);
                 SkASSERT(static_cast<int>(index) < count);
                 bitarray |= 1 << index;
             }
         }
     }

     for (int i = 0; i < count; ++i) {
         if (bitarray & (1 << i)) {
             *array->append() = refs[i];
         }
     }
 }

 static void test_gatherpixelrefs(skiatest::Reporter* reporter) {
     const int IW = 8;
     const int IH = IW;
     const SkScalar W = SkIntToScalar(IW);
     const SkScalar H = W;

     static const int N = 4;
     SkBitmap bm[N];
     SkPixelRef* refs[N];

     const SkPoint pos[] = {
         { 0, 0 }, { W, 0 }, { 0, H }, { W, H }
     };

     // Our convention is that the color components contain the index of their
     // corresponding bitmap/pixelref
     for (int i = 0; i < N; ++i) {
         make_bm(&bm[i], IW, IH, SkColorSetARGB(0xFF, i, i, i), true);
         refs[i] = bm[i].pixelRef();
     }

     static const DrawBitmapProc procs[] = {
         drawbitmap_proc, drawbitmaprect_proc, drawshader_proc
     };

     SkMWCRandom rand;
     for (size_t k = 0; k < SK_ARRAY_COUNT(procs); ++k) {
         SkAutoTUnref<SkPicture> pic(record_bitmaps(bm, pos, N, procs[k]));

         // quick check for a small piece of each quadrant, which should just
         // contain 1 bitmap.
         for (size_t  i = 0; i < SK_ARRAY_COUNT(pos); ++i) {
             SkRect r;
             r.set(2, 2, W - 2, H - 2);
             r.offset(pos[i].fX, pos[i].fY);
             SkAutoDataUnref data(SkPictureUtils::GatherPixelRefs(pic, r));
             REPORTER_ASSERT(reporter, data);
             int count = data->size() / sizeof(SkPixelRef*);
             REPORTER_ASSERT(reporter, 1 == count);
             REPORTER_ASSERT(reporter, *(SkPixelRef**)data->data() == refs[i]);
         }

         // Test a bunch of random (mostly) rects, and compare the gather results
         // with a deduced list of refs by looking at the colors drawn.
         for (int j = 0; j < 100; ++j) {
             SkRect r;
             rand_rect(&r, rand, 2*W, 2*H);

             SkBitmap result;
             draw(pic, r, &result);
             SkTDArray<SkPixelRef*> array;

             SkData* data = SkPictureUtils::GatherPixelRefs(pic, r);
             size_t dataSize = data ? data->size() : 0;
             int gatherCount = dataSize / sizeof(SkPixelRef*);
             SkASSERT(gatherCount * sizeof(SkPixelRef*) == dataSize);
             SkPixelRef** gatherRefs = data ? (SkPixelRef**)(data->data()) : NULL;
             SkAutoDataUnref adu(data);

             gather_from_colors(result, refs, N, &array);

             /*
              *  GatherPixelRefs is conservative, so it can return more bitmaps
              *  that we actually can see (usually because of conservative bounds
              *  inflation for antialiasing). Thus our check here is only that
              *  Gather didn't miss any that we actually saw. Even that isn't
              *  a strict requirement on Gather, which is meant to be quick and
              *  only mostly-correct, but at the moment this test should work.
              */
             for (int i = 0; i < array.count(); ++i) {
                 bool found = find(gatherRefs, array[i], gatherCount);
                 REPORTER_ASSERT(reporter, found);
 #if 0
                 // enable this block of code to debug failures, as it will rerun
                 // the case that failed.
                 if (!found) {
                     SkData* data = SkPictureUtils::GatherPixelRefs(pic, r);
                     size_t dataSize = data ? data->size() : 0;
                 }
 #endif
             }
         }
     }
 }

 #ifdef SK_DEBUG
 // Ensure that deleting SkPicturePlayback does not assert. Asserts only fire in debug mode, so only
 // run in debug mode.
 static void test_deleting_empty_playback() {
     SkPicture picture;
     // Creates an SkPictureRecord
     picture.beginRecording(0, 0);
     // Turns that into an SkPicturePlayback
     picture.endRecording();
     // Deletes the old SkPicturePlayback, and creates a new SkPictureRecord
     picture.beginRecording(0, 0);
 }

 // Ensure that serializing an empty picture does not assert. Likewise only runs in debug mode.
 static void test_serializing_empty_picture() {
     SkPicture picture;
     picture.beginRecording(0, 0);
     picture.endRecording();
     SkDynamicMemoryWStream stream;
     picture.serialize(&stream);
 }
 #endif

 static void rand_op(SkCanvas* canvas, SkMWCRandom& rand) {
     SkPaint paint;
     SkRect rect = SkRect::MakeWH(50, 50);

     SkScalar unit = rand.nextUScalar1();
     if (unit <= 0.3) {
 //        SkDebugf("save\n");
         canvas->save();
     } else if (unit <= 0.6) {
 //        SkDebugf("restore\n");
         canvas->restore();
     } else if (unit <= 0.9) {
 //        SkDebugf("clip\n");
         canvas->clipRect(rect);
     } else {
 //        SkDebugf("draw\n");
         canvas->drawPaint(paint);
     }
 }

 static void test_peephole() {
     SkMWCRandom rand;

     for (int j = 0; j < 100; j++) {
         SkMWCRandom rand2(rand); // remember the seed

         SkPicture picture;
         SkCanvas* canvas = picture.beginRecording(100, 100);

         for (int i = 0; i < 1000; ++i) {
             rand_op(canvas, rand);
         }
         picture.endRecording();

         rand = rand2;
     }

     {
         SkPicture picture;
         SkCanvas* canvas = picture.beginRecording(100, 100);
         SkRect rect = SkRect::MakeWH(50, 50);

         for (int i = 0; i < 100; ++i) {
             canvas->save();
         }
         while (canvas->getSaveCount() > 1) {
             canvas->clipRect(rect);
             canvas->restore();
         }
         picture.endRecording();
     }
 }

 #ifndef SK_DEBUG
 // Only test this is in release mode. We deliberately crash in debug mode, since a valid caller
 // should never do this.
 static void test_bad_bitmap() {
     // This bitmap has a width and height but no pixels. As a result, attempting to record it will
     // fail.
     SkBitmap bm;
     bm.setConfig(SkBitmap::kARGB_8888_Config, 100, 100);
     SkPicture picture;
     SkCanvas* recordingCanvas = picture.beginRecording(100, 100);
     recordingCanvas->drawBitmap(bm, 0, 0);
     picture.endRecording();

     SkCanvas canvas;
     canvas.drawPicture(picture);
 }
 #endif

 #include "SkData.h"
 #include "SkImageRef_GlobalPool.h"
 // Class to test SkPixelRef::onRefEncodedData, since there are currently no implementations in skia.
 class SkDataImageRef : public SkImageRef_GlobalPool {

 public:
     SkDataImageRef(SkMemoryStream* stream)
         : SkImageRef_GlobalPool(stream, SkBitmap::kNo_Config) {
         SkASSERT(stream != NULL);
         fData = stream->copyToData();
         this->setImmutable();
     }

     ~SkDataImageRef() {
         fData->unref();
     }

     virtual SkData* onRefEncodedData() SK_OVERRIDE {
         fData->ref();
         return fData;
     }

 private:
     SkData* fData;
 };

 #include "SkImageEncoder.h"

 static SkData* encode_bitmap_to_data(size_t* offset, const SkBitmap& bm) {
     *offset = 0;
     return SkImageEncoder::EncodeData(bm, SkImageEncoder::kPNG_Type, 100);
 }

 static SkData* serialized_picture_from_bitmap(const SkBitmap& bitmap) {
     SkPicture picture;
     SkCanvas* canvas = picture.beginRecording(bitmap.width(), bitmap.height());
     canvas->drawBitmap(bitmap, 0, 0);
     SkDynamicMemoryWStream wStream;
     picture.serialize(&wStream, &encode_bitmap_to_data);
     return wStream.copyToData();
 }

 struct ErrorContext {
     int fErrors;
     skiatest::Reporter* fReporter;
 };

 static void assert_one_parse_error_cb(SkError error, void* context) {
     ErrorContext* errorContext = static_cast<ErrorContext*>(context);
     errorContext->fErrors++;
     // This test only expects one error, and that is a kParseError. If there are others,
     // there is some unknown problem.
     REPORTER_ASSERT_MESSAGE(errorContext->fReporter, 1 == errorContext->fErrors,
                             "This threw more errors than expected.");
     REPORTER_ASSERT_MESSAGE(errorContext->fReporter, kParseError_SkError == error,
                             SkGetLastErrorString());
 }

 static void test_bitmap_with_encoded_data(skiatest::Reporter* reporter) {
     // Create a bitmap that will be encoded.
     SkBitmap original;
     make_bm(&original, 100, 100, SK_ColorBLUE, true);
     SkDynamicMemoryWStream wStream;
     if (!SkImageEncoder::EncodeStream(&wStream, original, SkImageEncoder::kPNG_Type, 100)) {
         return;
     }
     SkAutoDataUnref data(wStream.copyToData());
     SkMemoryStream memStream;
     memStream.setData(data);

     // Use the encoded bitmap as the data for an image ref.
     SkBitmap bm;
     SkAutoTUnref<SkDataImageRef> imageRef(SkNEW_ARGS(SkDataImageRef, (&memStream)));
     imageRef->getInfo(&bm);
     bm.setPixelRef(imageRef);

     // Write both bitmaps to pictures, and ensure that the resulting data streams are the same.
     // Flattening original will follow the old path of performing an encode, while flattening bm
     // will use the already encoded data.
     SkAutoDataUnref picture1(serialized_picture_from_bitmap(original));
     SkAutoDataUnref picture2(serialized_picture_from_bitmap(bm));
     REPORTER_ASSERT(reporter, picture1->equals(picture2));
     // Now test that a parse error was generated when trying to create a new SkPicture without
     // providing a function to decode the bitmap.
     ErrorContext context;
     context.fErrors = 0;
     context.fReporter = reporter;
     SkSetErrorCallback(assert_one_parse_error_cb, &context);
     SkMemoryStream pictureStream(picture1);
     SkClearLastError();
     SkAutoUnref pictureFromStream(SkPicture::CreateFromStream(&pictureStream, NULL));
     REPORTER_ASSERT(reporter, pictureFromStream.get() != NULL);
     SkClearLastError();
     SkSetErrorCallback(NULL, NULL);
 }

 static void test_clone_empty(skiatest::Reporter* reporter) {
     // This is a regression test for crbug.com/172062
     // Before the fix, we used to crash accessing a null pointer when we
     // had a picture with no paints. This test passes by not crashing.
     {
         SkPicture picture;
         picture.beginRecording(1, 1);
         picture.endRecording();
         SkPicture* destPicture = picture.clone();
         REPORTER_ASSERT(reporter, NULL != destPicture);
         destPicture->unref();
     }
     {
         // Test without call to endRecording
         SkPicture picture;
         picture.beginRecording(1, 1);
         SkPicture* destPicture = picture.clone();
         REPORTER_ASSERT(reporter, NULL != destPicture);
         destPicture->unref();
     }
 }

 static void test_clip_bound_opt(skiatest::Reporter* reporter) {
     // Test for crbug.com/229011
     SkRect rect1 = SkRect::MakeXYWH(SkIntToScalar(4), SkIntToScalar(4),
                                     SkIntToScalar(2), SkIntToScalar(2));
     SkRect rect2 = SkRect::MakeXYWH(SkIntToScalar(7), SkIntToScalar(7),
                                     SkIntToScalar(1), SkIntToScalar(1));
     SkRect rect3 = SkRect::MakeXYWH(SkIntToScalar(6), SkIntToScalar(6),
                                     SkIntToScalar(1), SkIntToScalar(1));

     SkPath invPath;
     invPath.addOval(rect1);
     invPath.setFillType(SkPath::kInverseEvenOdd_FillType);
     SkPath path;
     path.addOval(rect2);
     SkPath path2;
     path2.addOval(rect3);
     SkIRect clipBounds;
     // Minimalist test set for 100% code coverage of
     // SkPictureRecord::updateClipConservativelyUsingBounds
     {
         SkPicture picture;
         SkCanvas* canvas = picture.beginRecording(10, 10,
             SkPicture::kUsePathBoundsForClip_RecordingFlag);
         canvas->clipPath(invPath, SkRegion::kIntersect_Op);
         bool nonEmpty = canvas->getClipDeviceBounds(&clipBounds);
         REPORTER_ASSERT(reporter, true == nonEmpty);
         REPORTER_ASSERT(reporter, 0 == clipBounds.fLeft);
         REPORTER_ASSERT(reporter, 0 == clipBounds.fTop);
         REPORTER_ASSERT(reporter, 10 == clipBounds.fBottom);
         REPORTER_ASSERT(reporter, 10 == clipBounds.fRight);
     }
     {
         SkPicture picture;
         SkCanvas* canvas = picture.beginRecording(10, 10,
             SkPicture::kUsePathBoundsForClip_RecordingFlag);
         canvas->clipPath(path, SkRegion::kIntersect_Op);
         canvas->clipPath(invPath, SkRegion::kIntersect_Op);
         bool nonEmpty = canvas->getClipDeviceBounds(&clipBounds);
         REPORTER_ASSERT(reporter, true == nonEmpty);
         REPORTER_ASSERT(reporter, 7 == clipBounds.fLeft);
         REPORTER_ASSERT(reporter, 7 == clipBounds.fTop);
         REPORTER_ASSERT(reporter, 8 == clipBounds.fBottom);
         REPORTER_ASSERT(reporter, 8 == clipBounds.fRight);
     }
     {
         SkPicture picture;
         SkCanvas* canvas = picture.beginRecording(10, 10,
             SkPicture::kUsePathBoundsForClip_RecordingFlag);
         canvas->clipPath(path, SkRegion::kIntersect_Op);
         canvas->clipPath(invPath, SkRegion::kUnion_Op);
         bool nonEmpty = canvas->getClipDeviceBounds(&clipBounds);
         REPORTER_ASSERT(reporter, true == nonEmpty);
         REPORTER_ASSERT(reporter, 0 == clipBounds.fLeft);
         REPORTER_ASSERT(reporter, 0 == clipBounds.fTop);
         REPORTER_ASSERT(reporter, 10 == clipBounds.fBottom);
         REPORTER_ASSERT(reporter, 10 == clipBounds.fRight);
     }
     {
         SkPicture picture;
         SkCanvas* canvas = picture.beginRecording(10, 10,
             SkPicture::kUsePathBoundsForClip_RecordingFlag);
         canvas->clipPath(path, SkRegion::kDifference_Op);
         bool nonEmpty = canvas->getClipDeviceBounds(&clipBounds);
         REPORTER_ASSERT(reporter, true == nonEmpty);
         REPORTER_ASSERT(reporter, 0 == clipBounds.fLeft);
         REPORTER_ASSERT(reporter, 0 == clipBounds.fTop);
         REPORTER_ASSERT(reporter, 10 == clipBounds.fBottom);
         REPORTER_ASSERT(reporter, 10 == clipBounds.fRight);
     }
     {
         SkPicture picture;
         SkCanvas* canvas = picture.beginRecording(10, 10,
             SkPicture::kUsePathBoundsForClip_RecordingFlag);
         canvas->clipPath(path, SkRegion::kReverseDifference_Op);
         bool nonEmpty = canvas->getClipDeviceBounds(&clipBounds);
         // True clip is actually empty in this case, but the best
         // determination we can make using only bounds as input is that the
         // clip is included in the bounds of 'path'.
         REPORTER_ASSERT(reporter, true == nonEmpty);
         REPORTER_ASSERT(reporter, 7 == clipBounds.fLeft);
         REPORTER_ASSERT(reporter, 7 == clipBounds.fTop);
         REPORTER_ASSERT(reporter, 8 == clipBounds.fBottom);
         REPORTER_ASSERT(reporter, 8 == clipBounds.fRight);
     }
     {
         SkPicture picture;
         SkCanvas* canvas = picture.beginRecording(10, 10,
             SkPicture::kUsePathBoundsForClip_RecordingFlag);
         canvas->clipPath(path, SkRegion::kIntersect_Op);
         canvas->clipPath(path2, SkRegion::kXOR_Op);
         bool nonEmpty = canvas->getClipDeviceBounds(&clipBounds);
         REPORTER_ASSERT(reporter, true == nonEmpty);
         REPORTER_ASSERT(reporter, 6 == clipBounds.fLeft);
         REPORTER_ASSERT(reporter, 6 == clipBounds.fTop);
         REPORTER_ASSERT(reporter, 8 == clipBounds.fBottom);
         REPORTER_ASSERT(reporter, 8 == clipBounds.fRight);
     }
 }

 static void TestPicture(skiatest::Reporter* reporter) {
 #ifdef SK_DEBUG
     test_deleting_empty_playback();
     test_serializing_empty_picture();
 #else
     test_bad_bitmap();
 #endif
     test_peephole();
     test_gatherpixelrefs(reporter);
     test_bitmap_with_encoded_data(reporter);
     test_clone_empty(reporter);
     test_clip_bound_opt(reporter);
 }

 #include "TestClassDef.h"
 DEFINE_TESTCLASS("Pictures", PictureTestClass, TestPicture)
	/*
	* Copyright 2012 Google Inc.
	*
	* Use of this source code is governed by a BSD-style license that can be
	* found in the LICENSE file.
	*/
	#include "Test.h"
	#include "SkCanvas.h"
	#include "SkColorPriv.h"
	#include "SkData.h"
	#include "SkError.h"
	#include "SkPaint.h"
	#include "SkPicture.h"
	#include "SkRandom.h"
	#include "SkRRect.h"
	#include "SkShader.h"
	#include "SkStream.h"

	#include "SkPictureUtils.h"

	static void make_bm(SkBitmap* bm, int w, int h, SkColor color, bool immutable) {
	bm->setConfig(SkBitmap::kARGB_8888_Config, w, h);
	bm->allocPixels();
	bm->eraseColor(color);
	if (immutable) {
	bm->setImmutable();
	}
	}

	typedef void (DrawBitmapProc)(SkCanvas, const SkBitmap&, const SkPoint&);

	static void drawbitmap_proc(SkCanvas* canvas, const SkBitmap& bm,
	const SkPoint& pos) {
	canvas->drawBitmap(bm, pos.fX, pos.fY, NULL);
	}

	static void drawbitmaprect_proc(SkCanvas* canvas, const SkBitmap& bm,
	const SkPoint& pos) {
	SkRect r = {
	0, 0, SkIntToScalar(bm.width()), SkIntToScalar(bm.height())
	};
	r.offset(pos.fX, pos.fY);
	canvas->drawBitmapRectToRect(bm, NULL, r, NULL);
	}

	static void drawshader_proc(SkCanvas* canvas, const SkBitmap& bm,
	const SkPoint& pos) {
	SkRect r = {
	0, 0, SkIntToScalar(bm.width()), SkIntToScalar(bm.height())
	};
	r.offset(pos.fX, pos.fY);

	SkShader* s = SkShader::CreateBitmapShader(bm,
	SkShader::kClamp_TileMode,
	SkShader::kClamp_TileMode);
	SkPaint paint;
	paint.setShader(s)->unref();
	canvas->drawRect(r, paint);
	canvas->drawOval(r, paint);
	SkRRect rr;
	rr.setRectXY(r, 10, 10);
	canvas->drawRRect(rr, paint);
	}

	// Return a picture with the bitmaps drawn at the specified positions.
	static SkPicture* record_bitmaps(const SkBitmap bm[], const SkPoint pos[],
	int count, DrawBitmapProc proc) {
	SkPicture* pic = new SkPicture;
	SkCanvas* canvas = pic->beginRecording(1000, 1000);
	for (int i = 0; i < count; ++i) {
	proc(canvas, bm[i], pos[i]);
	}
	pic->endRecording();
	return pic;
	}

	static void rand_rect(SkRect* rect, SkMWCRandom& rand, SkScalar W, SkScalar H) {
	rect->fLeft = rand.nextRangeScalar(-W, 2*W);
	rect->fTop = rand.nextRangeScalar(-H, 2*H);
	rect->fRight = rect->fLeft + rand.nextRangeScalar(0, W);
	rect->fBottom = rect->fTop + rand.nextRangeScalar(0, H);

	// we integralize rect to make our tests more predictable, since Gather is
	// a little sloppy.
	SkIRect ir;
	rect->round(&ir);
	rect->set(ir);
	}

	// Allocate result to be large enough to hold subset, and then draw the picture
	// into it, offsetting by subset's top/left corner.
	static void draw(SkPicture* pic, const SkRect& subset, SkBitmap* result) {
	SkIRect ir;
	subset.roundOut(&ir);
	int w = ir.width();
	int h = ir.height();
	make_bm(result, w, h, 0, false);

	SkCanvas canvas(*result);
	canvas.translate(-SkIntToScalar(ir.left()), -SkIntToScalar(ir.top()));
	canvas.drawPicture(*pic);
	}

	template <typename T> int find_index(const T* array, T elem, int count) {
	for (int i = 0; i < count; ++i) {
	if (array[i] == elem) {
	return i;
	}
	}
	return -1;
	}

	// Return true if 'ref' is found in array[]
	static bool find(SkPixelRef const * const * array, SkPixelRef const * ref, int count) {
	return find_index<const SkPixelRef*>(array, ref, count) >= 0;
	}

	// Look at each pixel in bm, and if its color appears in colors[], find the
	// corresponding value in refs[] and append that ref into array, skipping
	// duplicates of the same value.
	static void gather_from_colors(const SkBitmap& bm, SkPixelRef* const refs[],
	int count, SkTDArray<SkPixelRef> array) {
	// Since we only want to return unique values in array, when we scan we just
	// set a bit for each index'd color found. In practice we only have a few
	// distinct colors, so we just use an int's bits as our array. Hence the
	// assert that count <= number-of-bits-in-our-int.
	SkASSERT((unsigned)count <= 32);
	uint32_t bitarray = 0;

	SkAutoLockPixels alp(bm);

	for (int y = 0; y < bm.height(); ++y) {
	for (int x = 0; x < bm.width(); ++x) {
	SkPMColor pmc = *bm.getAddr32(x, y);
	// the only good case where the color is not found would be if
	// the color is transparent, meaning no bitmap was drawn in that
	// pixel.
	if (pmc) {
	uint32_t index = SkGetPackedR32(pmc);
	SkASSERT(SkGetPackedG32(pmc) == index);
	SkASSERT(SkGetPackedB32(pmc) == index);
	SkASSERT(static_cast<int>(index) < count);
	bitarray \|= 1 << index;
	}
	}
	}

	for (int i = 0; i < count; ++i) {
	if (bitarray & (1 << i)) {
	*array->append() = refs[i];
	}
	}
	}

	static void test_gatherpixelrefs(skiatest::Reporter* reporter) {
	const int IW = 8;
	const int IH = IW;
	const SkScalar W = SkIntToScalar(IW);
	const SkScalar H = W;

	static const int N = 4;
	SkBitmap bm[N];
	SkPixelRef* refs[N];

	const SkPoint pos[] = {
	{ 0, 0 }, { W, 0 }, { 0, H }, { W, H }
	};

	// Our convention is that the color components contain the index of their
	// corresponding bitmap/pixelref
	for (int i = 0; i < N; ++i) {
	make_bm(&bm[i], IW, IH, SkColorSetARGB(0xFF, i, i, i), true);
	refs[i] = bm[i].pixelRef();
	}

	static const DrawBitmapProc procs[] = {
	drawbitmap_proc, drawbitmaprect_proc, drawshader_proc
	};

	SkMWCRandom rand;
	for (size_t k = 0; k < SK_ARRAY_COUNT(procs); ++k) {
	SkAutoTUnref<SkPicture> pic(record_bitmaps(bm, pos, N, procs[k]));

	// quick check for a small piece of each quadrant, which should just
	// contain 1 bitmap.
	for (size_t i = 0; i < SK_ARRAY_COUNT(pos); ++i) {
	SkRect r;
	r.set(2, 2, W - 2, H - 2);
	r.offset(pos[i].fX, pos[i].fY);
	SkAutoDataUnref data(SkPictureUtils::GatherPixelRefs(pic, r));
	REPORTER_ASSERT(reporter, data);
	int count = data->size() / sizeof(SkPixelRef*);
	REPORTER_ASSERT(reporter, 1 == count);
	REPORTER_ASSERT(reporter, (SkPixelRef*)data->data() == refs[i]);
	}

	// Test a bunch of random (mostly) rects, and compare the gather results
	// with a deduced list of refs by looking at the colors drawn.
	for (int j = 0; j < 100; ++j) {
	SkRect r;
	rand_rect(&r, rand, 2W, 2H);

	SkBitmap result;
	draw(pic, r, &result);
	SkTDArray<SkPixelRef*> array;

	SkData* data = SkPictureUtils::GatherPixelRefs(pic, r);
	size_t dataSize = data ? data->size() : 0;
	int gatherCount = dataSize / sizeof(SkPixelRef*);
	SkASSERT(gatherCount * sizeof(SkPixelRef*) == dataSize);
	SkPixelRef gatherRefs = data ? (SkPixelRef)(data->data()) : NULL;
	SkAutoDataUnref adu(data);

	gather_from_colors(result, refs, N, &array);

	/*
	* GatherPixelRefs is conservative, so it can return more bitmaps
	* that we actually can see (usually because of conservative bounds
	* inflation for antialiasing). Thus our check here is only that
	* Gather didn't miss any that we actually saw. Even that isn't
	* a strict requirement on Gather, which is meant to be quick and
	* only mostly-correct, but at the moment this test should work.
	*/
	for (int i = 0; i < array.count(); ++i) {
	bool found = find(gatherRefs, array[i], gatherCount);
	REPORTER_ASSERT(reporter, found);
	#if 0
	// enable this block of code to debug failures, as it will rerun
	// the case that failed.
	if (!found) {
	SkData* data = SkPictureUtils::GatherPixelRefs(pic, r);
	size_t dataSize = data ? data->size() : 0;
	}
	#endif
	}
	}
	}
	}

	#ifdef SK_DEBUG
	// Ensure that deleting SkPicturePlayback does not assert. Asserts only fire in debug mode, so only
	// run in debug mode.
	static void test_deleting_empty_playback() {
	SkPicture picture;
	// Creates an SkPictureRecord
	picture.beginRecording(0, 0);
	// Turns that into an SkPicturePlayback
	picture.endRecording();
	// Deletes the old SkPicturePlayback, and creates a new SkPictureRecord
	picture.beginRecording(0, 0);
	}

	// Ensure that serializing an empty picture does not assert. Likewise only runs in debug mode.
	static void test_serializing_empty_picture() {
	SkPicture picture;
	picture.beginRecording(0, 0);
	picture.endRecording();
	SkDynamicMemoryWStream stream;
	picture.serialize(&stream);
	}
	#endif

	static void rand_op(SkCanvas* canvas, SkMWCRandom& rand) {
	SkPaint paint;
	SkRect rect = SkRect::MakeWH(50, 50);

	SkScalar unit = rand.nextUScalar1();
	if (unit <= 0.3) {
	// SkDebugf("save\n");
	canvas->save();
	} else if (unit <= 0.6) {
	// SkDebugf("restore\n");
	canvas->restore();
	} else if (unit <= 0.9) {
	// SkDebugf("clip\n");
	canvas->clipRect(rect);
	} else {
	// SkDebugf("draw\n");
	canvas->drawPaint(paint);
	}
	}

	static void test_peephole() {
	SkMWCRandom rand;

	for (int j = 0; j < 100; j++) {
	SkMWCRandom rand2(rand); // remember the seed

	SkPicture picture;
	SkCanvas* canvas = picture.beginRecording(100, 100);

	for (int i = 0; i < 1000; ++i) {
	rand_op(canvas, rand);
	}
	picture.endRecording();

	rand = rand2;
	}

	{
	SkPicture picture;
	SkCanvas* canvas = picture.beginRecording(100, 100);
	SkRect rect = SkRect::MakeWH(50, 50);

	for (int i = 0; i < 100; ++i) {
	canvas->save();
	}
	while (canvas->getSaveCount() > 1) {
	canvas->clipRect(rect);
	canvas->restore();
	}
	picture.endRecording();
	}
	}

	#ifndef SK_DEBUG
	// Only test this is in release mode. We deliberately crash in debug mode, since a valid caller
	// should never do this.
	static void test_bad_bitmap() {
	// This bitmap has a width and height but no pixels. As a result, attempting to record it will
	// fail.
	SkBitmap bm;
	bm.setConfig(SkBitmap::kARGB_8888_Config, 100, 100);
	SkPicture picture;
	SkCanvas* recordingCanvas = picture.beginRecording(100, 100);
	recordingCanvas->drawBitmap(bm, 0, 0);
	picture.endRecording();

	SkCanvas canvas;
	canvas.drawPicture(picture);
	}
	#endif

	#include "SkData.h"
	#include "SkImageRef_GlobalPool.h"
	// Class to test SkPixelRef::onRefEncodedData, since there are currently no implementations in skia.
	class SkDataImageRef : public SkImageRef_GlobalPool {

	public:
	SkDataImageRef(SkMemoryStream* stream)
	: SkImageRef_GlobalPool(stream, SkBitmap::kNo_Config) {
	SkASSERT(stream != NULL);
	fData = stream->copyToData();
	this->setImmutable();
	}

	~SkDataImageRef() {
	fData->unref();
	}

	virtual SkData* onRefEncodedData() SK_OVERRIDE {
	fData->ref();
	return fData;
	}

	private:
	SkData* fData;
	};

	#include "SkImageEncoder.h"

	static SkData* encode_bitmap_to_data(size_t* offset, const SkBitmap& bm) {
	*offset = 0;
	return SkImageEncoder::EncodeData(bm, SkImageEncoder::kPNG_Type, 100);
	}

	static SkData* serialized_picture_from_bitmap(const SkBitmap& bitmap) {
	SkPicture picture;
	SkCanvas* canvas = picture.beginRecording(bitmap.width(), bitmap.height());
	canvas->drawBitmap(bitmap, 0, 0);
	SkDynamicMemoryWStream wStream;
	picture.serialize(&wStream, &encode_bitmap_to_data);
	return wStream.copyToData();
	}

	struct ErrorContext {
	int fErrors;
	skiatest::Reporter* fReporter;
	};

	static void assert_one_parse_error_cb(SkError error, void* context) {
	ErrorContext* errorContext = static_cast<ErrorContext*>(context);
	errorContext->fErrors++;
	// This test only expects one error, and that is a kParseError. If there are others,
	// there is some unknown problem.
	REPORTER_ASSERT_MESSAGE(errorContext->fReporter, 1 == errorContext->fErrors,
	"This threw more errors than expected.");
	REPORTER_ASSERT_MESSAGE(errorContext->fReporter, kParseError_SkError == error,
	SkGetLastErrorString());
	}

	static void test_bitmap_with_encoded_data(skiatest::Reporter* reporter) {
	// Create a bitmap that will be encoded.
	SkBitmap original;
	make_bm(&original, 100, 100, SK_ColorBLUE, true);
	SkDynamicMemoryWStream wStream;
	if (!SkImageEncoder::EncodeStream(&wStream, original, SkImageEncoder::kPNG_Type, 100)) {
	return;
	}
	SkAutoDataUnref data(wStream.copyToData());
	SkMemoryStream memStream;
	memStream.setData(data);

	// Use the encoded bitmap as the data for an image ref.
	SkBitmap bm;
	SkAutoTUnref<SkDataImageRef> imageRef(SkNEW_ARGS(SkDataImageRef, (&memStream)));
	imageRef->getInfo(&bm);
	bm.setPixelRef(imageRef);

	// Write both bitmaps to pictures, and ensure that the resulting data streams are the same.
	// Flattening original will follow the old path of performing an encode, while flattening bm
	// will use the already encoded data.
	SkAutoDataUnref picture1(serialized_picture_from_bitmap(original));
	SkAutoDataUnref picture2(serialized_picture_from_bitmap(bm));
	REPORTER_ASSERT(reporter, picture1->equals(picture2));
	// Now test that a parse error was generated when trying to create a new SkPicture without
	// providing a function to decode the bitmap.
	ErrorContext context;
	context.fErrors = 0;
	context.fReporter = reporter;
	SkSetErrorCallback(assert_one_parse_error_cb, &context);
	SkMemoryStream pictureStream(picture1);
	SkClearLastError();
	SkAutoUnref pictureFromStream(SkPicture::CreateFromStream(&pictureStream, NULL));
	REPORTER_ASSERT(reporter, pictureFromStream.get() != NULL);
	SkClearLastError();
	SkSetErrorCallback(NULL, NULL);
	}

	static void test_clone_empty(skiatest::Reporter* reporter) {
	// This is a regression test for crbug.com/172062
	// Before the fix, we used to crash accessing a null pointer when we
	// had a picture with no paints. This test passes by not crashing.
	{
	SkPicture picture;
	picture.beginRecording(1, 1);
	picture.endRecording();
	SkPicture* destPicture = picture.clone();
	REPORTER_ASSERT(reporter, NULL != destPicture);
	destPicture->unref();
	}
	{
	// Test without call to endRecording
	SkPicture picture;
	picture.beginRecording(1, 1);
	SkPicture* destPicture = picture.clone();
	REPORTER_ASSERT(reporter, NULL != destPicture);
	destPicture->unref();
	}
	}

	static void test_clip_bound_opt(skiatest::Reporter* reporter) {
	// Test for crbug.com/229011
	SkRect rect1 = SkRect::MakeXYWH(SkIntToScalar(4), SkIntToScalar(4),
	SkIntToScalar(2), SkIntToScalar(2));
	SkRect rect2 = SkRect::MakeXYWH(SkIntToScalar(7), SkIntToScalar(7),
	SkIntToScalar(1), SkIntToScalar(1));
	SkRect rect3 = SkRect::MakeXYWH(SkIntToScalar(6), SkIntToScalar(6),
	SkIntToScalar(1), SkIntToScalar(1));

	SkPath invPath;
	invPath.addOval(rect1);
	invPath.setFillType(SkPath::kInverseEvenOdd_FillType);
	SkPath path;
	path.addOval(rect2);
	SkPath path2;
	path2.addOval(rect3);
	SkIRect clipBounds;
	// Minimalist test set for 100% code coverage of
	// SkPictureRecord::updateClipConservativelyUsingBounds
	{
	SkPicture picture;
	SkCanvas* canvas = picture.beginRecording(10, 10,
	SkPicture::kUsePathBoundsForClip_RecordingFlag);
	canvas->clipPath(invPath, SkRegion::kIntersect_Op);
	bool nonEmpty = canvas->getClipDeviceBounds(&clipBounds);
	REPORTER_ASSERT(reporter, true == nonEmpty);
	REPORTER_ASSERT(reporter, 0 == clipBounds.fLeft);
	REPORTER_ASSERT(reporter, 0 == clipBounds.fTop);
	REPORTER_ASSERT(reporter, 10 == clipBounds.fBottom);
	REPORTER_ASSERT(reporter, 10 == clipBounds.fRight);
	}
	{
	SkPicture picture;
	SkCanvas* canvas = picture.beginRecording(10, 10,
	SkPicture::kUsePathBoundsForClip_RecordingFlag);
	canvas->clipPath(path, SkRegion::kIntersect_Op);
	canvas->clipPath(invPath, SkRegion::kIntersect_Op);
	bool nonEmpty = canvas->getClipDeviceBounds(&clipBounds);
	REPORTER_ASSERT(reporter, true == nonEmpty);
	REPORTER_ASSERT(reporter, 7 == clipBounds.fLeft);
	REPORTER_ASSERT(reporter, 7 == clipBounds.fTop);
	REPORTER_ASSERT(reporter, 8 == clipBounds.fBottom);
	REPORTER_ASSERT(reporter, 8 == clipBounds.fRight);
	}
	{
	SkPicture picture;
	SkCanvas* canvas = picture.beginRecording(10, 10,
	SkPicture::kUsePathBoundsForClip_RecordingFlag);
	canvas->clipPath(path, SkRegion::kIntersect_Op);
	canvas->clipPath(invPath, SkRegion::kUnion_Op);
	bool nonEmpty = canvas->getClipDeviceBounds(&clipBounds);
	REPORTER_ASSERT(reporter, true == nonEmpty);
	REPORTER_ASSERT(reporter, 0 == clipBounds.fLeft);
	REPORTER_ASSERT(reporter, 0 == clipBounds.fTop);
	REPORTER_ASSERT(reporter, 10 == clipBounds.fBottom);
	REPORTER_ASSERT(reporter, 10 == clipBounds.fRight);
	}
	{
	SkPicture picture;
	SkCanvas* canvas = picture.beginRecording(10, 10,
	SkPicture::kUsePathBoundsForClip_RecordingFlag);
	canvas->clipPath(path, SkRegion::kDifference_Op);
	bool nonEmpty = canvas->getClipDeviceBounds(&clipBounds);
	REPORTER_ASSERT(reporter, true == nonEmpty);
	REPORTER_ASSERT(reporter, 0 == clipBounds.fLeft);
	REPORTER_ASSERT(reporter, 0 == clipBounds.fTop);
	REPORTER_ASSERT(reporter, 10 == clipBounds.fBottom);
	REPORTER_ASSERT(reporter, 10 == clipBounds.fRight);
	}
	{
	SkPicture picture;
	SkCanvas* canvas = picture.beginRecording(10, 10,
	SkPicture::kUsePathBoundsForClip_RecordingFlag);
	canvas->clipPath(path, SkRegion::kReverseDifference_Op);
	bool nonEmpty = canvas->getClipDeviceBounds(&clipBounds);
	// True clip is actually empty in this case, but the best
	// determination we can make using only bounds as input is that the
	// clip is included in the bounds of 'path'.
	REPORTER_ASSERT(reporter, true == nonEmpty);
	REPORTER_ASSERT(reporter, 7 == clipBounds.fLeft);
	REPORTER_ASSERT(reporter, 7 == clipBounds.fTop);
	REPORTER_ASSERT(reporter, 8 == clipBounds.fBottom);
	REPORTER_ASSERT(reporter, 8 == clipBounds.fRight);
	}
	{
	SkPicture picture;
	SkCanvas* canvas = picture.beginRecording(10, 10,
	SkPicture::kUsePathBoundsForClip_RecordingFlag);
	canvas->clipPath(path, SkRegion::kIntersect_Op);
	canvas->clipPath(path2, SkRegion::kXOR_Op);
	bool nonEmpty = canvas->getClipDeviceBounds(&clipBounds);
	REPORTER_ASSERT(reporter, true == nonEmpty);
	REPORTER_ASSERT(reporter, 6 == clipBounds.fLeft);
	REPORTER_ASSERT(reporter, 6 == clipBounds.fTop);
	REPORTER_ASSERT(reporter, 8 == clipBounds.fBottom);
	REPORTER_ASSERT(reporter, 8 == clipBounds.fRight);
	}
	}

	static void TestPicture(skiatest::Reporter* reporter) {
	#ifdef SK_DEBUG
	test_deleting_empty_playback();
	test_serializing_empty_picture();
	#else
	test_bad_bitmap();
	#endif
	test_peephole();
	test_gatherpixelrefs(reporter);
	test_bitmap_with_encoded_data(reporter);
	test_clone_empty(reporter);
	test_clip_bound_opt(reporter);
	}

	#include "TestClassDef.h"
	DEFINE_TESTCLASS("Pictures", PictureTestClass, TestPicture)