aboutsummaryrefslogtreecommitdiffhomepage
path: root/src/core/SkWriteBuffer.cpp
blob: faa7f00b08d35d9523d2381127b68b8937fd67d7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358

/*
 * 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 "SkBitmapHeap.h"
#include "SkData.h"
#include "SkPixelRef.h"
#include "SkPtrRecorder.h"
#include "SkStream.h"
#include "SkTypeface.h"

SkWriteBuffer::SkWriteBuffer(uint32_t flags)
    : fFlags(flags)
    , fFactorySet(NULL)
    , fNamedFactorySet(NULL)
    , fBitmapHeap(NULL)
    , fTFSet(NULL) {
}

SkWriteBuffer::SkWriteBuffer(void* storage, size_t storageSize, uint32_t flags)
    : fFlags(flags)
    , fFactorySet(NULL)
    , fNamedFactorySet(NULL)
    , fWriter(storage, storageSize)
    , fBitmapHeap(NULL)
    , fTFSet(NULL) {
}

SkWriteBuffer::~SkWriteBuffer() {
    SkSafeUnref(fFactorySet);
    SkSafeUnref(fNamedFactorySet);
    SkSafeUnref(fBitmapHeap);
    SkSafeUnref(fTFSet);
}

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

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

void SkWriteBuffer::writeFixed(SkFixed value) {
    fWriter.write32(value);
}

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

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

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

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

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

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

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

void SkWriteBuffer::writeEncodedString(const void* value, size_t byteLength,
                                              SkPaint::TextEncoding encoding) {
    fWriter.writeInt(encoding);
    fWriter.writeInt(SkToU32(byteLength));
    fWriter.write(value, byteLength);
}


void SkWriteBuffer::writeColor(const SkColor& color) {
    fWriter.write32(color);
}

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

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

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

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

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

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

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

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

size_t SkWriteBuffer::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 SkWriteBuffer::writeToStream(SkWStream* stream) {
    return fWriter.writeToStream(stream);
}

static void write_encoded_bitmap(SkWriteBuffer* buffer, SkData* data,
                                 const SkIPoint& origin) {
    buffer->writeUInt(SkToU32(data->size()));
    buffer->getWriter32()->writePad(data->data(), data->size());
    buffer->write32(origin.fX);
    buffer->write32(origin.fY);
}

void SkWriteBuffer::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 three ways, in order of priority:
    // 1. If there is an SkBitmapHeap, store it in the heap. The client can avoid serializing the
    //    bitmap entirely or serialize it later as desired. A boolean value of true will be written
    //    to the stream to signify that a heap was used.
    // 2. 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.
    // 3. 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.
    bool useBitmapHeap = fBitmapHeap != NULL;
    // Write a bool: true if the SkBitmapHeap is to be used, in which case the reader must use an
    // SkBitmapHeapReader to read the SkBitmap. False if the bitmap was serialized another way.
    this->writeBool(useBitmapHeap);
    if (useBitmapHeap) {
        SkASSERT(NULL == fPixelSerializer);
        int32_t slot = fBitmapHeap->insert(bitmap);
        fWriter.write32(slot);
        // crbug.com/155875
        // The generation ID is not required information. We write it to prevent collisions
        // in SkFlatDictionary.  It is possible to get a collision when a previously
        // unflattened (i.e. stale) instance of a similar flattenable is in the dictionary
        // and the instance currently being written is re-using the same slot from the
        // bitmap heap.
        fWriter.write32(bitmap.getGenerationID());
        return;
    }

    SkPixelRef* pixelRef = bitmap.pixelRef();
    if (pixelRef) {
        // see if the pixelref already has an encoded version
        SkAutoDataUnref existingData(pixelRef->refEncodedData());
        if (existingData.get() != NULL) {
            // Assumes that if the client did not set a serializer, they are
            // happy to get the encoded data.
            if (!fPixelSerializer || fPixelSerializer->useEncodedData(existingData->data(),
                                                                      existingData->size())) {
                write_encoded_bitmap(this, existingData, bitmap.pixelRefOrigin());
                return;
            }
        }

        // see if the caller wants to manually encode
        SkAutoPixmapUnlock result;
        if (fPixelSerializer && bitmap.requestLock(&result)) {
            const SkPixmap& pmap = result.pixmap();
            SkASSERT(NULL == fBitmapHeap);
            SkAutoDataUnref data(fPixelSerializer->encodePixels(pmap.info(),
                                                                pmap.addr(),
                                                                pmap.rowBytes()));
            if (data.get() != NULL) {
                // 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, SkIPoint::Make(0, 0));
                return;
            }
        }
    }

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

static bool try_write_encoded(SkWriteBuffer* buffer, SkData* encoded) {
    SkPixelSerializer* ps = buffer->getPixelSerializer();
    // Assumes that if the client did not set a serializer, they are
    // happy to get the encoded data.
    if (!ps || ps->useEncodedData(encoded->data(), encoded->size())) {
        write_encoded_bitmap(buffer, encoded, SkIPoint::Make(0, 0));
        return true;
    }
    return false;
}

void SkWriteBuffer::writeImage(const SkImage* image) {
    this->writeInt(image->width());
    this->writeInt(image->height());

    SkAutoTUnref<SkData> encoded(image->refEncoded());
    if (encoded && try_write_encoded(this, encoded)) {
        return;
    }

    encoded.reset(image->encode(SkImageEncoder::kPNG_Type, 100));
    if (encoded && try_write_encoded(this, encoded)) {
        return;
    }
    
    this->writeUInt(0); // signal no pixels (in place of the size of the encoded data)
}

void SkWriteBuffer::writeTypeface(SkTypeface* obj) {
    if (NULL == obj || NULL == fTFSet) {
        fWriter.write32(0);
    } else {
        fWriter.write32(fTFSet->add(obj));
    }
}

SkFactorySet* SkWriteBuffer::setFactoryRecorder(SkFactorySet* rec) {
    SkRefCnt_SafeAssign(fFactorySet, rec);
    if (fNamedFactorySet != NULL) {
        fNamedFactorySet->unref();
        fNamedFactorySet = NULL;
    }
    return rec;
}

SkNamedFactorySet* SkWriteBuffer::setNamedFactoryRecorder(SkNamedFactorySet* rec) {
    SkRefCnt_SafeAssign(fNamedFactorySet, rec);
    if (fFactorySet != NULL) {
        fFactorySet->unref();
        fFactorySet = NULL;
    }
    return rec;
}

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

void SkWriteBuffer::setBitmapHeap(SkBitmapHeap* bitmapHeap) {
    SkRefCnt_SafeAssign(fBitmapHeap, bitmapHeap);
    if (bitmapHeap != NULL) {
        SkASSERT(NULL == fPixelSerializer);
        fPixelSerializer.reset(NULL);
    }
}

void SkWriteBuffer::setPixelSerializer(SkPixelSerializer* serializer) {
    fPixelSerializer.reset(serializer);
    if (serializer) {
        serializer->ref();
        SkASSERT(NULL == fBitmapHeap);
        SkSafeUnref(fBitmapHeap);
        fBitmapHeap = NULL;
    }
}

void SkWriteBuffer::writeFlattenable(const SkFlattenable* flattenable) {
    /*
     *  If we have a factoryset, then the first 32bits tell us...
     *       0: failure to write the flattenable
     *      >0: (1-based) index into the SkFactorySet or SkNamedFactorySet
     *  If we don't have a factoryset, then the first "ptr" is either the
     *  factory, or null for failure.
     *
     *  The distinction is important, since 0-index is 32bits (always), but a
     *  0-functionptr might be 32 or 64 bits.
     */
    if (NULL == flattenable) {
        if (this->isValidating()) {
            this->writeString("");
        } else if (fFactorySet != NULL || fNamedFactorySet != NULL) {
            this->write32(0);
        } else {
            this->writeFunctionPtr(NULL);
        }
        return;
    }

    SkFlattenable::Factory factory = flattenable->getFactory();
    SkASSERT(factory != NULL);

    /*
     *  We can write 1 of 3 versions of the flattenable:
     *  1.  function-ptr : this is the fastest for the reader, but assumes that
     *      the writer and reader are in the same process.
     *  2.  index into fFactorySet : This is 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.
     *  3.  index into fNamedFactorySet. fNamedFactorySet will also store the
     *      name. SkGPipe uses this technique so it can write the name to its
     *      stream before writing the flattenable.
     */
    if (this->isValidating()) {
        this->writeString(flattenable->getTypeName());
    } else if (fFactorySet) {
        this->write32(fFactorySet->add(factory));
    } else if (fNamedFactorySet) {
        int32_t index = fNamedFactorySet->find(factory);
        this->write32(index);
        if (0 == index) {
            return;
        }
    } else {
        this->writeFunctionPtr((void*)factory);
    }

    // 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));
}