/*
* Copyright 2007 The Android Open Source Project
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkAtomics.h"
#include "SkImageGenerator.h"
#include "SkMathPriv.h"
#include "SkPicture.h"
#include "SkPictureCommon.h"
#include "SkPictureData.h"
#include "SkPicturePlayback.h"
#include "SkPictureRecord.h"
#include "SkPictureRecorder.h"
#include "SkSerialProcs.h"
// When we read/write the SkPictInfo via a stream, we have a sentinel byte right after the info.
// Note: in the read/write buffer versions, we have a slightly different convention:
// We have a sentinel int32_t:
// 0 : failure
// 1 : PictureData
// <0 : -size of the custom data
enum {
kFailure_TrailingStreamByteAfterPictInfo = 0, // nothing follows
kPictureData_TrailingStreamByteAfterPictInfo = 1, // SkPictureData follows
kCustom_TrailingStreamByteAfterPictInfo = 2, // -size32 follows
};
/* SkPicture impl. This handles generic responsibilities like unique IDs and serialization. */
SkPicture::SkPicture() : fUniqueID(0) {}
uint32_t SkPicture::uniqueID() const {
static uint32_t gNextID = 1;
uint32_t id = sk_atomic_load(&fUniqueID, sk_memory_order_relaxed);
while (id == 0) {
uint32_t next = sk_atomic_fetch_add(&gNextID, 1u);
if (sk_atomic_compare_exchange(&fUniqueID, &id, next,
sk_memory_order_relaxed,
sk_memory_order_relaxed)) {
id = next;
} else {
// sk_atomic_compare_exchange replaced id with the current value of fUniqueID.
}
}
return id;
}
static const char kMagic[] = { 's', 'k', 'i', 'a', 'p', 'i', 'c', 't' };
SkPictInfo SkPicture::createHeader() const {
SkPictInfo info;
// Copy magic bytes at the beginning of the header
static_assert(sizeof(kMagic) == 8, "");
static_assert(sizeof(kMagic) == sizeof(info.fMagic), "");
memcpy(info.fMagic, kMagic, sizeof(kMagic));
// Set picture info after magic bytes in the header
info.setVersion(CURRENT_PICTURE_VERSION);
info.fCullRect = this->cullRect();
return info;
}
bool SkPicture::IsValidPictInfo(const SkPictInfo& info) {
if (0 != memcmp(info.fMagic, kMagic, sizeof(kMagic))) {
return false;
}
if (info.getVersion() < MIN_PICTURE_VERSION || info.getVersion() > CURRENT_PICTURE_VERSION) {
return false;
}
return true;
}
bool SkPicture::StreamIsSKP(SkStream* stream, SkPictInfo* pInfo) {
if (!stream) {
return false;
}
SkPictInfo info;
SkASSERT(sizeof(kMagic) == sizeof(info.fMagic));
if (!stream->read(&info.fMagic, sizeof(kMagic))) {
return false;
}
info.setVersion( stream->readU32());
info.fCullRect.fLeft = stream->readScalar();
info.fCullRect.fTop = stream->readScalar();
info.fCullRect.fRight = stream->readScalar();
info.fCullRect.fBottom = stream->readScalar();
if (info.getVersion() < SkReadBuffer::kRemoveHeaderFlags_Version) {
(void)stream->readU32(); // used to be flags
}
if (IsValidPictInfo(info)) {
if (pInfo) { *pInfo = info; }
return true;
}
return false;
}
bool SkPicture_StreamIsSKP(SkStream* stream, SkPictInfo* pInfo) {
return SkPicture::StreamIsSKP(stream, pInfo);
}
bool SkPicture::BufferIsSKP(SkReadBuffer* buffer, SkPictInfo* pInfo) {
SkPictInfo info;
SkASSERT(sizeof(kMagic) == sizeof(info.fMagic));
if (!buffer->readByteArray(&info.fMagic, sizeof(kMagic))) {
return false;
}
info.setVersion(buffer->readUInt());
buffer->readRect(&info.fCullRect);
if (info.getVersion() < SkReadBuffer::kRemoveHeaderFlags_Version) {
(void)buffer->readUInt(); // used to be flags
}
if (IsValidPictInfo(info)) {
if (pInfo) { *pInfo = info; }
return true;
}
return false;
}
sk_sp<SkPicture> SkPicture::Forwardport(const SkPictInfo& info,
const SkPictureData* data,
SkReadBuffer* buffer) {
if (!data) {
return nullptr;
}
if (!data->opData()) {
return nullptr;
}
SkPicturePlayback playback(data);
SkPictureRecorder r;
playback.draw(r.beginRecording(info.fCullRect), nullptr/*no callback*/, buffer);
return r.finishRecordingAsPicture();
}
sk_sp<SkPicture> SkPicture::MakeFromStream(SkStream* stream, const SkDeserialProcs* procs) {
return MakeFromStream(stream, procs, nullptr);
}
sk_sp<SkPicture> SkPicture::MakeFromData(const void* data, size_t size,
const SkDeserialProcs* procs) {
if (!data) {
return nullptr;
}
SkMemoryStream stream(data, size);
return MakeFromStream(&stream, procs, nullptr);
}
sk_sp<SkPicture> SkPicture::MakeFromData(const SkData* data, const SkDeserialProcs* procs) {
if (!data) {
return nullptr;
}
SkMemoryStream stream(data->data(), data->size());
return MakeFromStream(&stream, procs, nullptr);
}
sk_sp<SkPicture> SkPicture::MakeFromStream(SkStream* stream, const SkDeserialProcs* procsPtr,
SkTypefacePlayback* typefaces) {
SkPictInfo info;
if (!StreamIsSKP(stream, &info)) {
return nullptr;
}
SkDeserialProcs procs;
if (procsPtr) {
procs = *procsPtr;
}
switch (stream->readU8()) {
case kPictureData_TrailingStreamByteAfterPictInfo: {
std::unique_ptr<SkPictureData> data(
SkPictureData::CreateFromStream(stream, info, procs, typefaces));
return Forwardport(info, data.get(), nullptr);
}
case kCustom_TrailingStreamByteAfterPictInfo: {
int32_t ssize = stream->readS32();
if (ssize >= 0 || !procs.fPictureProc) {
return nullptr;
}
size_t size = sk_negate_to_size_t(ssize);
auto data = SkData::MakeUninitialized(size);
if (stream->read(data->writable_data(), size) != size) {
return nullptr;
}
return procs.fPictureProc(data->data(), size, procs.fPictureCtx);
}
default: // fall through to error return
break;
}
return nullptr;
}
sk_sp<SkPicture> SkPicture::MakeFromBuffer(SkReadBuffer& buffer) {
SkPictInfo info;
if (!BufferIsSKP(&buffer, &info)) {
return nullptr;
}
// size should be 0, 1, or negative
int32_t ssize = buffer.read32();
if (ssize < 0) {
const SkDeserialProcs& procs = buffer.fProcs;
if (!procs.fPictureProc) {
return nullptr;
}
size_t size = sk_negate_to_size_t(ssize);
return procs.fPictureProc(buffer.skip(size), size, procs.fPictureCtx);
}
if (ssize != 1) {
// 1 is the magic 'size' that means SkPictureData follows
return nullptr;
}
std::unique_ptr<SkPictureData> data(SkPictureData::CreateFromBuffer(buffer, info));
return Forwardport(info, data.get(), &buffer);
}
SkPictureData* SkPicture::backport() const {
SkPictInfo info = this->createHeader();
SkPictureRecord rec(SkISize::Make(info.fCullRect.width(), info.fCullRect.height()), 0/*flags*/);
rec.beginRecording();
this->playback(&rec);
rec.endRecording();
return new SkPictureData(rec, info);
}
void SkPicture::serialize(SkWStream* stream, const SkSerialProcs* procs) const {
this->serialize(stream, procs, nullptr);
}
sk_sp<SkData> SkPicture::serialize(const SkSerialProcs* procs) const {
SkDynamicMemoryWStream stream;
this->serialize(&stream, procs, nullptr);
return stream.detachAsData();
}
static sk_sp<SkData> custom_serialize(const SkPicture* picture, const SkSerialProcs& procs) {
if (procs.fPictureProc) {
auto data = procs.fPictureProc(const_cast<SkPicture*>(picture), procs.fPictureCtx);
if (data) {
size_t size = data->size();
if (!sk_64_isS32(size) || size <= 1) {
return SkData::MakeEmpty();
}
return data;
}
}
return nullptr;
}
static bool write_pad32(SkWStream* stream, const void* data, size_t size) {
if (!stream->write(data, size)) {
return false;
}
if (size & 3) {
uint32_t zero = 0;
return stream->write(&zero, 4 - (size & 3));
}
return true;
}
void SkPicture::serialize(SkWStream* stream, const SkSerialProcs* procsPtr,
SkRefCntSet* typefaceSet) const {
SkSerialProcs procs;
if (procsPtr) {
procs = *procsPtr;
}
SkPictInfo info = this->createHeader();
stream->write(&info, sizeof(info));
if (auto custom = custom_serialize(this, procs)) {
int32_t size = SkToS32(custom->size());
if (size == 0) {
stream->write8(kFailure_TrailingStreamByteAfterPictInfo);
return;
}
stream->write8(kCustom_TrailingStreamByteAfterPictInfo);
stream->write32(-size); // negative for custom format
write_pad32(stream, custom->data(), size);
return;
}
std::unique_ptr<SkPictureData> data(this->backport());
if (data) {
stream->write8(kPictureData_TrailingStreamByteAfterPictInfo);
data->serialize(stream, procs, typefaceSet);
} else {
stream->write8(kFailure_TrailingStreamByteAfterPictInfo);
}
}
void SkPicture::flatten(SkWriteBuffer& buffer) const {
SkPictInfo info = this->createHeader();
std::unique_ptr<SkPictureData> data(this->backport());
buffer.writeByteArray(&info.fMagic, sizeof(info.fMagic));
buffer.writeUInt(info.getVersion());
buffer.writeRect(info.fCullRect);
if (auto custom = custom_serialize(this, buffer.fProcs)) {
int32_t size = SkToS32(custom->size());
buffer.write32(-size); // negative for custom format
buffer.writePad32(custom->data(), size);
return;
}
if (data) {
buffer.write32(1); // special size meaning SkPictureData
data->flatten(buffer);
} else {
buffer.write32(0); // signal no content
}
}
sk_sp<SkPicture> SkPicture::MakePlaceholder(SkRect cull) {
struct Placeholder : public SkPicture {
explicit Placeholder(SkRect cull) : fCull(cull) {}
void playback(SkCanvas*, AbortCallback*) const override { }
// approximateOpCount() needs to be greater than kMaxPictureOpsToUnrollInsteadOfRef
// in SkCanvas.cpp to avoid that unrolling. SK_MaxS32 can't not be big enough!
int approximateOpCount() const override { return SK_MaxS32; }
size_t approximateBytesUsed() const override { return sizeof(*this); }
SkRect cullRect() const override { return fCull; }
SkRect fCull;
};
return sk_make_sp<Placeholder>(cull);
}