src/core/SkWriteBuffer.cpp - skia - Git at Google

 /*
  * 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 "SkWriteBuffer.h"
 #include "SkBitmap.h"
 #include "SkData.h"
 #include "SkDeduper.h"
 #include "SkPixelRef.h"
 #include "SkPtrRecorder.h"
 #include "SkStream.h"
 #include "SkTypeface.h"

 ///////////////////////////////////////////////////////////////////////////////////////////////////

 SkBinaryWriteBuffer::SkBinaryWriteBuffer(uint32_t flags)
     : fFlags(flags)
     , fFactorySet(nullptr)
     , fTFSet(nullptr) {
 }

 SkBinaryWriteBuffer::SkBinaryWriteBuffer(void* storage, size_t storageSize, uint32_t flags)
     : fFlags(flags)
     , fFactorySet(nullptr)
     , fWriter(storage, storageSize)
     , fTFSet(nullptr) {
 }

 SkBinaryWriteBuffer::~SkBinaryWriteBuffer() {
     SkSafeUnref(fFactorySet);
     SkSafeUnref(fTFSet);
 }

 void SkBinaryWriteBuffer::writeByteArray(const void* data, size_t size) {
     fWriter.write32(SkToU32(size));
     fWriter.writePad(data, size);
 }

 void SkBinaryWriteBuffer::writeBool(bool value) {
     fWriter.writeBool(value);
 }

 void SkBinaryWriteBuffer::writeScalar(SkScalar value) {
     fWriter.writeScalar(value);
 }

 void SkBinaryWriteBuffer::writeScalarArray(const SkScalar* value, uint32_t count) {
     fWriter.write32(count);
     fWriter.write(value, count * sizeof(SkScalar));
 }

 void SkBinaryWriteBuffer::writeInt(int32_t value) {
     fWriter.write32(value);
 }

 void SkBinaryWriteBuffer::writeIntArray(const int32_t* value, uint32_t count) {
     fWriter.write32(count);
     fWriter.write(value, count * sizeof(int32_t));
 }

 void SkBinaryWriteBuffer::writeUInt(uint32_t value) {
     fWriter.write32(value);
 }

 void SkBinaryWriteBuffer::writeString(const char* value) {
     fWriter.writeString(value);
 }

 void SkBinaryWriteBuffer::writeColor(SkColor color) {
     fWriter.write32(color);
 }

 void SkBinaryWriteBuffer::writeColorArray(const SkColor* color, uint32_t count) {
     fWriter.write32(count);
     fWriter.write(color, count * sizeof(SkColor));
 }

 void SkBinaryWriteBuffer::writeColor4f(const SkColor4f& color) {
     fWriter.write(&color, sizeof(SkColor4f));
 }

 void SkBinaryWriteBuffer::writeColor4fArray(const SkColor4f* color, uint32_t count) {
     fWriter.write32(count);
     fWriter.write(color, count * sizeof(SkColor4f));
 }

 void SkBinaryWriteBuffer::writePoint(const SkPoint& point) {
     fWriter.writeScalar(point.fX);
     fWriter.writeScalar(point.fY);
 }

 void SkBinaryWriteBuffer::writePointArray(const SkPoint* point, uint32_t count) {
     fWriter.write32(count);
     fWriter.write(point, count * sizeof(SkPoint));
 }

 void SkBinaryWriteBuffer::writeMatrix(const SkMatrix& matrix) {
     fWriter.writeMatrix(matrix);
 }

 void SkBinaryWriteBuffer::writeIRect(const SkIRect& rect) {
     fWriter.write(&rect, sizeof(SkIRect));
 }

 void SkBinaryWriteBuffer::writeRect(const SkRect& rect) {
     fWriter.writeRect(rect);
 }

 void SkBinaryWriteBuffer::writeRegion(const SkRegion& region) {
     fWriter.writeRegion(region);
 }

 void SkBinaryWriteBuffer::writePath(const SkPath& path) {
     fWriter.writePath(path);
 }

 size_t SkBinaryWriteBuffer::writeStream(SkStream* stream, size_t length) {
     fWriter.write32(SkToU32(length));
     size_t bytesWritten = fWriter.readFromStream(stream, length);
     if (bytesWritten < length) {
         fWriter.reservePad(length - bytesWritten);
     }
     return bytesWritten;
 }

 bool SkBinaryWriteBuffer::writeToStream(SkWStream* stream) {
     return fWriter.writeToStream(stream);
 }

 static void write_encoded_bitmap(SkBinaryWriteBuffer* buffer, SkData* data,
                                  const SkIPoint& origin) {
     buffer->writeDataAsByteArray(data);
     buffer->write32(origin.fX);
     buffer->write32(origin.fY);
 }

 void SkBinaryWriteBuffer::writeBitmap(const SkBitmap& bitmap) {
     // Record the width and height. This way if readBitmap fails a dummy bitmap can be drawn at the
     // right size.
     this->writeInt(bitmap.width());
     this->writeInt(bitmap.height());

     // Record information about the bitmap in one of two ways, in order of priority:
     // 1. If there is a function for encoding bitmaps, use it to write an encoded version of the
     //    bitmap. After writing a boolean value of false, signifying that a heap was not used, write
     //    the size of the encoded data. A non-zero size signifies that encoded data was written.
     // 2. Call SkBitmap::flatten. After writing a boolean value of false, signifying that a heap was
     //    not used, write a zero to signify that the data was not encoded.

     // Write a bool to indicate that we did not use an SkBitmapHeap. That feature is deprecated.
     this->writeBool(false);

     // see if the caller wants to manually encode
     SkPixmap result;
     if (fPixelSerializer && bitmap.peekPixels(&result)) {
         sk_sp<SkData> data(fPixelSerializer->encode(result));
         if (data) {
             // if we have to "encode" the bitmap, then we assume there is no
             // offset to share, since we are effectively creating a new pixelref
             write_encoded_bitmap(this, data.get(), SkIPoint::Make(0, 0));
             return;
         }
     }

     this->writeUInt(0); // signal raw pixels
     SkBitmap::WriteRawPixels(this, bitmap);
 }

 void SkBinaryWriteBuffer::writeImage(const SkImage* image) {
     if (fDeduper) {
         this->write32(fDeduper->findOrDefineImage(const_cast<SkImage*>(image)));
         return;
     }

     this->writeInt(image->width());
     this->writeInt(image->height());

     sk_sp<SkData> encoded(image->encode(this->getPixelSerializer()));
     if (encoded && encoded->size() > 0) {
         write_encoded_bitmap(this, encoded.get(), SkIPoint::Make(0, 0));
         return;
     }

     SkBitmap bm;
     if (image->asLegacyBitmap(&bm, SkImage::kRO_LegacyBitmapMode)) {
         this->writeUInt(1);  // signal raw pixels.
         SkBitmap::WriteRawPixels(this, bm);
         return;
     }

     this->writeUInt(0); // signal no pixels (in place of the size of the encoded data)
 }

 void SkBinaryWriteBuffer::writeTypeface(SkTypeface* obj) {
     if (fDeduper) {
         this->write32(fDeduper->findOrDefineTypeface(obj));
         return;
     }

     if (nullptr == obj || nullptr == fTFSet) {
         fWriter.write32(0);
     } else {
         fWriter.write32(fTFSet->add(obj));
     }
 }

 void SkBinaryWriteBuffer::writePaint(const SkPaint& paint) {
     paint.flatten(*this);
 }

 SkFactorySet* SkBinaryWriteBuffer::setFactoryRecorder(SkFactorySet* rec) {
     SkRefCnt_SafeAssign(fFactorySet, rec);
     return rec;
 }

 SkRefCntSet* SkBinaryWriteBuffer::setTypefaceRecorder(SkRefCntSet* rec) {
     SkRefCnt_SafeAssign(fTFSet, rec);
     return rec;
 }

 void SkBinaryWriteBuffer::setPixelSerializer(sk_sp<SkPixelSerializer> serializer) {
     fPixelSerializer = std::move(serializer);
 }

 void SkBinaryWriteBuffer::writeFlattenable(const SkFlattenable* flattenable) {
     if (nullptr == flattenable) {
         this->write32(0);
         return;
     }

     if (fDeduper) {
         this->write32(fDeduper->findOrDefineFactory(const_cast<SkFlattenable*>(flattenable)));
     } else {
         /*
          *  We can write 1 of 2 versions of the flattenable:
          *  1.  index into fFactorySet : This assumes the writer will later
          *      resolve the function-ptrs into strings for its reader. SkPicture
          *      does exactly this, by writing a table of names (matching the indices)
          *      up front in its serialized form.
          *  2.  string name of the flattenable or index into fFlattenableDict:  We
          *      store the string to allow the reader to specify its own factories
          *      after write time.  In order to improve compression, if we have
          *      already written the string, we write its index instead.
          */
         if (fFactorySet) {
             SkFlattenable::Factory factory = flattenable->getFactory();
             SkASSERT(factory);
             this->write32(fFactorySet->add(factory));
         } else {
             const char* name = flattenable->getTypeName();
             SkASSERT(name);
             SkString key(name);
             if (uint32_t* indexPtr = fFlattenableDict.find(key)) {
                 // We will write the index as a 32-bit int.  We want the first byte
                 // that we send to be zero - this will act as a sentinel that we
                 // have an index (not a string).  This means that we will send the
                 // the index shifted left by 8.  The remaining 24-bits should be
                 // plenty to store the index.  Note that this strategy depends on
                 // being little endian.
                 SkASSERT(0 == *indexPtr >> 24);
                 this->write32(*indexPtr << 8);
             } else {
                 // Otherwise write the string.  Clients should not use the empty
                 // string as a name, or we will have a problem.
                 SkASSERT(strcmp("", name));
                 this->writeString(name);

                 // Add key to dictionary.
                 fFlattenableDict.set(key, fFlattenableDict.count() + 1);
             }
         }
     }

     // make room for the size of the flattened object
     (void)fWriter.reserve(sizeof(uint32_t));
     // record the current size, so we can subtract after the object writes.
     size_t offset = fWriter.bytesWritten();
     // now flatten the object
     flattenable->flatten(*this);
     size_t objSize = fWriter.bytesWritten() - offset;
     // record the obj's size
     fWriter.overwriteTAt(offset - sizeof(uint32_t), SkToU32(objSize));
 }
	/*
	* 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 "SkWriteBuffer.h"
	#include "SkBitmap.h"
	#include "SkData.h"
	#include "SkDeduper.h"
	#include "SkPixelRef.h"
	#include "SkPtrRecorder.h"
	#include "SkStream.h"
	#include "SkTypeface.h"

	///////////////////////////////////////////////////////////////////////////////////////////////////

	SkBinaryWriteBuffer::SkBinaryWriteBuffer(uint32_t flags)
	: fFlags(flags)
	, fFactorySet(nullptr)
	, fTFSet(nullptr) {
	}

	SkBinaryWriteBuffer::SkBinaryWriteBuffer(void* storage, size_t storageSize, uint32_t flags)
	: fFlags(flags)
	, fFactorySet(nullptr)
	, fWriter(storage, storageSize)
	, fTFSet(nullptr) {
	}

	SkBinaryWriteBuffer::~SkBinaryWriteBuffer() {
	SkSafeUnref(fFactorySet);
	SkSafeUnref(fTFSet);
	}

	void SkBinaryWriteBuffer::writeByteArray(const void* data, size_t size) {
	fWriter.write32(SkToU32(size));
	fWriter.writePad(data, size);
	}

	void SkBinaryWriteBuffer::writeBool(bool value) {
	fWriter.writeBool(value);
	}

	void SkBinaryWriteBuffer::writeScalar(SkScalar value) {
	fWriter.writeScalar(value);
	}

	void SkBinaryWriteBuffer::writeScalarArray(const SkScalar* value, uint32_t count) {
	fWriter.write32(count);
	fWriter.write(value, count * sizeof(SkScalar));
	}

	void SkBinaryWriteBuffer::writeInt(int32_t value) {
	fWriter.write32(value);
	}

	void SkBinaryWriteBuffer::writeIntArray(const int32_t* value, uint32_t count) {
	fWriter.write32(count);
	fWriter.write(value, count * sizeof(int32_t));
	}

	void SkBinaryWriteBuffer::writeUInt(uint32_t value) {
	fWriter.write32(value);
	}

	void SkBinaryWriteBuffer::writeString(const char* value) {
	fWriter.writeString(value);
	}

	void SkBinaryWriteBuffer::writeColor(SkColor color) {
	fWriter.write32(color);
	}

	void SkBinaryWriteBuffer::writeColorArray(const SkColor* color, uint32_t count) {
	fWriter.write32(count);
	fWriter.write(color, count * sizeof(SkColor));
	}

	void SkBinaryWriteBuffer::writeColor4f(const SkColor4f& color) {
	fWriter.write(&color, sizeof(SkColor4f));
	}

	void SkBinaryWriteBuffer::writeColor4fArray(const SkColor4f* color, uint32_t count) {
	fWriter.write32(count);
	fWriter.write(color, count * sizeof(SkColor4f));
	}

	void SkBinaryWriteBuffer::writePoint(const SkPoint& point) {
	fWriter.writeScalar(point.fX);
	fWriter.writeScalar(point.fY);
	}

	void SkBinaryWriteBuffer::writePointArray(const SkPoint* point, uint32_t count) {
	fWriter.write32(count);
	fWriter.write(point, count * sizeof(SkPoint));
	}

	void SkBinaryWriteBuffer::writeMatrix(const SkMatrix& matrix) {
	fWriter.writeMatrix(matrix);
	}

	void SkBinaryWriteBuffer::writeIRect(const SkIRect& rect) {
	fWriter.write(&rect, sizeof(SkIRect));
	}

	void SkBinaryWriteBuffer::writeRect(const SkRect& rect) {
	fWriter.writeRect(rect);
	}

	void SkBinaryWriteBuffer::writeRegion(const SkRegion& region) {
	fWriter.writeRegion(region);
	}

	void SkBinaryWriteBuffer::writePath(const SkPath& path) {
	fWriter.writePath(path);
	}

	size_t SkBinaryWriteBuffer::writeStream(SkStream* stream, size_t length) {
	fWriter.write32(SkToU32(length));
	size_t bytesWritten = fWriter.readFromStream(stream, length);
	if (bytesWritten < length) {
	fWriter.reservePad(length - bytesWritten);
	}
	return bytesWritten;
	}

	bool SkBinaryWriteBuffer::writeToStream(SkWStream* stream) {
	return fWriter.writeToStream(stream);
	}

	static void write_encoded_bitmap(SkBinaryWriteBuffer* buffer, SkData* data,
	const SkIPoint& origin) {
	buffer->writeDataAsByteArray(data);
	buffer->write32(origin.fX);
	buffer->write32(origin.fY);
	}

	void SkBinaryWriteBuffer::writeBitmap(const SkBitmap& bitmap) {
	// Record the width and height. This way if readBitmap fails a dummy bitmap can be drawn at the
	// right size.
	this->writeInt(bitmap.width());
	this->writeInt(bitmap.height());

	// Record information about the bitmap in one of two ways, in order of priority:
	// 1. If there is a function for encoding bitmaps, use it to write an encoded version of the
	// bitmap. After writing a boolean value of false, signifying that a heap was not used, write
	// the size of the encoded data. A non-zero size signifies that encoded data was written.
	// 2. Call SkBitmap::flatten. After writing a boolean value of false, signifying that a heap was
	// not used, write a zero to signify that the data was not encoded.

	// Write a bool to indicate that we did not use an SkBitmapHeap. That feature is deprecated.
	this->writeBool(false);

	// see if the caller wants to manually encode
	SkPixmap result;
	if (fPixelSerializer && bitmap.peekPixels(&result)) {
	sk_sp<SkData> data(fPixelSerializer->encode(result));
	if (data) {
	// if we have to "encode" the bitmap, then we assume there is no
	// offset to share, since we are effectively creating a new pixelref
	write_encoded_bitmap(this, data.get(), SkIPoint::Make(0, 0));
	return;
	}
	}

	this->writeUInt(0); // signal raw pixels
	SkBitmap::WriteRawPixels(this, bitmap);
	}

	void SkBinaryWriteBuffer::writeImage(const SkImage* image) {
	if (fDeduper) {
	this->write32(fDeduper->findOrDefineImage(const_cast<SkImage*>(image)));
	return;
	}

	this->writeInt(image->width());
	this->writeInt(image->height());

	sk_sp<SkData> encoded(image->encode(this->getPixelSerializer()));
	if (encoded && encoded->size() > 0) {
	write_encoded_bitmap(this, encoded.get(), SkIPoint::Make(0, 0));
	return;
	}

	SkBitmap bm;
	if (image->asLegacyBitmap(&bm, SkImage::kRO_LegacyBitmapMode)) {
	this->writeUInt(1); // signal raw pixels.
	SkBitmap::WriteRawPixels(this, bm);
	return;
	}

	this->writeUInt(0); // signal no pixels (in place of the size of the encoded data)
	}

	void SkBinaryWriteBuffer::writeTypeface(SkTypeface* obj) {
	if (fDeduper) {
	this->write32(fDeduper->findOrDefineTypeface(obj));
	return;
	}

	if (nullptr == obj \|\| nullptr == fTFSet) {
	fWriter.write32(0);
	} else {
	fWriter.write32(fTFSet->add(obj));
	}
	}

	void SkBinaryWriteBuffer::writePaint(const SkPaint& paint) {
	paint.flatten(*this);
	}

	SkFactorySet* SkBinaryWriteBuffer::setFactoryRecorder(SkFactorySet* rec) {
	SkRefCnt_SafeAssign(fFactorySet, rec);
	return rec;
	}

	SkRefCntSet* SkBinaryWriteBuffer::setTypefaceRecorder(SkRefCntSet* rec) {
	SkRefCnt_SafeAssign(fTFSet, rec);
	return rec;
	}

	void SkBinaryWriteBuffer::setPixelSerializer(sk_sp<SkPixelSerializer> serializer) {
	fPixelSerializer = std::move(serializer);
	}

	void SkBinaryWriteBuffer::writeFlattenable(const SkFlattenable* flattenable) {
	if (nullptr == flattenable) {
	this->write32(0);
	return;
	}

	if (fDeduper) {
	this->write32(fDeduper->findOrDefineFactory(const_cast<SkFlattenable*>(flattenable)));
	} else {
	/*
	* We can write 1 of 2 versions of the flattenable:
	* 1. index into fFactorySet : This assumes the writer will later
	* resolve the function-ptrs into strings for its reader. SkPicture
	* does exactly this, by writing a table of names (matching the indices)
	* up front in its serialized form.
	* 2. string name of the flattenable or index into fFlattenableDict: We
	* store the string to allow the reader to specify its own factories
	* after write time. In order to improve compression, if we have
	* already written the string, we write its index instead.
	*/
	if (fFactorySet) {
	SkFlattenable::Factory factory = flattenable->getFactory();
	SkASSERT(factory);
	this->write32(fFactorySet->add(factory));
	} else {
	const char* name = flattenable->getTypeName();
	SkASSERT(name);
	SkString key(name);
	if (uint32_t* indexPtr = fFlattenableDict.find(key)) {
	// We will write the index as a 32-bit int. We want the first byte
	// that we send to be zero - this will act as a sentinel that we
	// have an index (not a string). This means that we will send the
	// the index shifted left by 8. The remaining 24-bits should be
	// plenty to store the index. Note that this strategy depends on
	// being little endian.
	SkASSERT(0 == *indexPtr >> 24);
	this->write32(*indexPtr << 8);
	} else {
	// Otherwise write the string. Clients should not use the empty
	// string as a name, or we will have a problem.
	SkASSERT(strcmp("", name));
	this->writeString(name);

	// Add key to dictionary.
	fFlattenableDict.set(key, fFlattenableDict.count() + 1);
	}
	}
	}

	// make room for the size of the flattened object
	(void)fWriter.reserve(sizeof(uint32_t));
	// record the current size, so we can subtract after the object writes.
	size_t offset = fWriter.bytesWritten();
	// now flatten the object
	flattenable->flatten(*this);
	size_t objSize = fWriter.bytesWritten() - offset;
	// record the obj's size
	fWriter.overwriteTAt(offset - sizeof(uint32_t), SkToU32(objSize));
	}