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/*
* 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.
*/
#ifndef SkPicture_DEFINED
#define SkPicture_DEFINED
#include "include/core/SkRect.h"
#include "include/core/SkRefCnt.h"
#include "include/core/SkSamplingOptions.h"
#include "include/core/SkShader.h"
#include "include/core/SkTileMode.h"
#include "include/core/SkTypes.h"
class SkCanvas;
class SkData;
struct SkDeserialProcs;
class SkImage;
class SkMatrix;
struct SkSerialProcs;
class SkStream;
class SkWStream;
/** \class SkPicture
SkPicture records drawing commands made to SkCanvas. The command stream may be
played in whole or in part at a later time.
SkPicture is an abstract class. SkPicture may be generated by SkPictureRecorder
or SkDrawable, or from SkPicture previously saved to SkData or SkStream.
SkPicture may contain any SkCanvas drawing command, as well as one or more
SkCanvas matrix or SkCanvas clip. SkPicture has a cull SkRect, which is used as
a bounding box hint. To limit SkPicture bounds, use SkCanvas clip when
recording or drawing SkPicture.
*/
class SK_API SkPicture : public SkRefCnt {
public:
~SkPicture() override;
/** Recreates SkPicture that was serialized into a stream. Returns constructed SkPicture
if successful; otherwise, returns nullptr. Fails if data does not permit
constructing valid SkPicture.
procs->fPictureProc permits supplying a custom function to decode SkPicture.
If procs->fPictureProc is nullptr, default decoding is used. procs->fPictureCtx
may be used to provide user context to procs->fPictureProc; procs->fPictureProc
is called with a pointer to data, data byte length, and user context.
@param stream container for serial data
@param procs custom serial data decoders; may be nullptr
@return SkPicture constructed from stream data
*/
static sk_sp<SkPicture> MakeFromStream(SkStream* stream,
const SkDeserialProcs* procs = nullptr);
/** Recreates SkPicture that was serialized into data. Returns constructed SkPicture
if successful; otherwise, returns nullptr. Fails if data does not permit
constructing valid SkPicture.
procs->fPictureProc permits supplying a custom function to decode SkPicture.
If procs->fPictureProc is nullptr, default decoding is used. procs->fPictureCtx
may be used to provide user context to procs->fPictureProc; procs->fPictureProc
is called with a pointer to data, data byte length, and user context.
@param data container for serial data
@param procs custom serial data decoders; may be nullptr
@return SkPicture constructed from data
*/
static sk_sp<SkPicture> MakeFromData(const SkData* data,
const SkDeserialProcs* procs = nullptr);
/**
@param data pointer to serial data
@param size size of data
@param procs custom serial data decoders; may be nullptr
@return SkPicture constructed from data
*/
static sk_sp<SkPicture> MakeFromData(const void* data, size_t size,
const SkDeserialProcs* procs = nullptr);
/** \class SkPicture::AbortCallback
AbortCallback is an abstract class. An implementation of AbortCallback may
passed as a parameter to SkPicture::playback, to stop it before all drawing
commands have been processed.
If AbortCallback::abort returns true, SkPicture::playback is interrupted.
*/
class SK_API AbortCallback {
public:
/** Has no effect.
*/
virtual ~AbortCallback() = default;
/** Stops SkPicture playback when some condition is met. A subclass of
AbortCallback provides an override for abort() that can stop SkPicture::playback.
The part of SkPicture drawn when aborted is undefined. SkPicture instantiations are
free to stop drawing at different points during playback.
If the abort happens inside one or more calls to SkCanvas::save(), stack
of SkCanvas matrix and SkCanvas clip values is restored to its state before
SkPicture::playback was called.
@return true to stop playback
example: https://fiddle.skia.org/c/@Picture_AbortCallback_abort
*/
virtual bool abort() = 0;
protected:
AbortCallback() = default;
AbortCallback(const AbortCallback&) = delete;
AbortCallback& operator=(const AbortCallback&) = delete;
};
/** Replays the drawing commands on the specified canvas. In the case that the
commands are recorded, each command in the SkPicture is sent separately to canvas.
To add a single command to draw SkPicture to recording canvas, call
SkCanvas::drawPicture instead.
@param canvas receiver of drawing commands
@param callback allows interruption of playback
example: https://fiddle.skia.org/c/@Picture_playback
*/
virtual void playback(SkCanvas* canvas, AbortCallback* callback = nullptr) const = 0;
/** Returns cull SkRect for this picture, passed in when SkPicture was created.
Returned SkRect does not specify clipping SkRect for SkPicture; cull is hint
of SkPicture bounds.
SkPicture is free to discard recorded drawing commands that fall outside
cull.
@return bounds passed when SkPicture was created
example: https://fiddle.skia.org/c/@Picture_cullRect
*/
virtual SkRect cullRect() const = 0;
/** Returns a non-zero value unique among SkPicture in Skia process.
@return identifier for SkPicture
*/
uint32_t uniqueID() const { return fUniqueID; }
/** Returns storage containing SkData describing SkPicture, using optional custom
encoders.
procs->fPictureProc permits supplying a custom function to encode SkPicture.
If procs->fPictureProc is nullptr, default encoding is used. procs->fPictureCtx
may be used to provide user context to procs->fPictureProc; procs->fPictureProc
is called with a pointer to SkPicture and user context.
@param procs custom serial data encoders; may be nullptr
@return storage containing serialized SkPicture
example: https://fiddle.skia.org/c/@Picture_serialize
*/
sk_sp<SkData> serialize(const SkSerialProcs* procs = nullptr) const;
/** Writes picture to stream, using optional custom encoders.
procs->fPictureProc permits supplying a custom function to encode SkPicture.
If procs->fPictureProc is nullptr, default encoding is used. procs->fPictureCtx
may be used to provide user context to procs->fPictureProc; procs->fPictureProc
is called with a pointer to SkPicture and user context.
@param stream writable serial data stream
@param procs custom serial data encoders; may be nullptr
example: https://fiddle.skia.org/c/@Picture_serialize_2
*/
void serialize(SkWStream* stream, const SkSerialProcs* procs = nullptr) const;
/** Returns a placeholder SkPicture. Result does not draw, and contains only
cull SkRect, a hint of its bounds. Result is immutable; it cannot be changed
later. Result identifier is unique.
Returned placeholder can be intercepted during playback to insert other
commands into SkCanvas draw stream.
@param cull placeholder dimensions
@return placeholder with unique identifier
example: https://fiddle.skia.org/c/@Picture_MakePlaceholder
*/
static sk_sp<SkPicture> MakePlaceholder(SkRect cull);
/** Returns the approximate number of operations in SkPicture. Returned value
may be greater or less than the number of SkCanvas calls
recorded: some calls may be recorded as more than one operation, other
calls may be optimized away.
@param nested if true, include the op-counts of nested pictures as well, else
just return count the ops in the top-level picture.
@return approximate operation count
example: https://fiddle.skia.org/c/@Picture_approximateOpCount
*/
virtual int approximateOpCount(bool nested = false) const = 0;
/** Returns the approximate byte size of SkPicture. Does not include large objects
referenced by SkPicture.
@return approximate size
example: https://fiddle.skia.org/c/@Picture_approximateBytesUsed
*/
virtual size_t approximateBytesUsed() const = 0;
/** Return a new shader that will draw with this picture.
*
* @param tmx The tiling mode to use when sampling in the x-direction.
* @param tmy The tiling mode to use when sampling in the y-direction.
* @param mode How to filter the tiles
* @param localMatrix Optional matrix used when sampling
* @param tile The tile rectangle in picture coordinates: this represents the subset
* (or superset) of the picture used when building a tile. It is not
* affected by localMatrix and does not imply scaling (only translation
* and cropping). If null, the tile rect is considered equal to the picture
* bounds.
* @return Returns a new shader object. Note: this function never returns null.
*/
sk_sp<SkShader> makeShader(SkTileMode tmx, SkTileMode tmy, SkFilterMode mode,
const SkMatrix* localMatrix, const SkRect* tileRect) const;
sk_sp<SkShader> makeShader(SkTileMode tmx, SkTileMode tmy, SkFilterMode mode) const {
return this->makeShader(tmx, tmy, mode, nullptr, nullptr);
}
private:
// Allowed subclasses.
SkPicture();
friend class SkBigPicture;
friend class SkEmptyPicture;
friend class SkPicturePriv;
template <typename> friend class SkMiniPicture;
void serialize(SkWStream*, const SkSerialProcs*, class SkRefCntSet* typefaces,
bool textBlobsOnly=false) const;
static sk_sp<SkPicture> MakeFromStream(SkStream*, const SkDeserialProcs*,
class SkTypefacePlayback*);
friend class SkPictureData;
/** Return true if the SkStream/Buffer represents a serialized picture, and
fills out SkPictInfo. After this function returns, the data source is not
rewound so it will have to be manually reset before passing to
MakeFromStream or MakeFromBuffer. Note, MakeFromStream and
MakeFromBuffer perform this check internally so these entry points are
intended for stand alone tools.
If false is returned, SkPictInfo is unmodified.
*/
static bool StreamIsSKP(SkStream*, struct SkPictInfo*);
static bool BufferIsSKP(class SkReadBuffer*, struct SkPictInfo*);
friend bool SkPicture_StreamIsSKP(SkStream*, struct SkPictInfo*);
// Returns NULL if this is not an SkBigPicture.
virtual const class SkBigPicture* asSkBigPicture() const { return nullptr; }
friend struct SkPathCounter;
static bool IsValidPictInfo(const struct SkPictInfo& info);
static sk_sp<SkPicture> Forwardport(const struct SkPictInfo&,
const class SkPictureData*,
class SkReadBuffer* buffer);
struct SkPictInfo createHeader() const;
class SkPictureData* backport() const;
uint32_t fUniqueID;
mutable std::atomic<bool> fAddedToCache{false};
};
#endif