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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 "SkBitmap.h"

 #include "SkImageDecoder.h"

 #include "SkRefCnt.h"

 class SkBBoxHierarchy;

 class SkCanvas;

 class SkDrawPictureCallback;

 class SkData;

 class SkPicturePlayback;

 class SkPictureRecord;

 class SkStream;

 class SkWStream;

 struct SkPictInfo;

 /** \class SkPicture

     The SkPicture class records the drawing commands made to a canvas, to

     be played back at a later time.

 */

 class SK_API SkPicture : public SkRefCnt {

 public:

     SK_DECLARE_INST_COUNT(SkPicture)

     // AccelData provides a base class for device-specific acceleration

     // data. It is added to the picture via a call to a device's optimize

     // method.

     class AccelData : public SkRefCnt {

     public:

         typedef uint8_t Domain;

         typedef uint32_t Key;

         AccelData(Key key) : fKey(key) { }

         const Key& getKey() const { return fKey; }

         // This entry point allows user's to get a unique domain prefix

         // for their keys

         static Domain GenerateDomain();

     private:

         Key fKey;

         typedef SkRefCnt INHERITED;

     };

     /** The constructor prepares the picture to record.

         @param width the width of the virtual device the picture records.

         @param height the height of the virtual device the picture records.

     */

     SkPicture();

     /** Make a copy of the contents of src. If src records more drawing after

         this call, those elements will not appear in this picture.

     */

     SkPicture(const SkPicture& src);

     /**  PRIVATE / EXPERIMENTAL -- do not call */

     void EXPERIMENTAL_addAccelData(const AccelData* data) {

         SkRefCnt_SafeAssign(fAccelData, data);

     }

     /**  PRIVATE / EXPERIMENTAL -- do not call */

     const AccelData* EXPERIMENTAL_getAccelData(AccelData::Key key) const {

         if (NULL != fAccelData && fAccelData->getKey() == key) {

             return fAccelData;

         }

         return NULL;

     }

     /**

      *  Function signature defining a function that sets up an SkBitmap from encoded data. On

      *  success, the SkBitmap should have its Config, width, height, rowBytes and pixelref set.

      *  If the installed pixelref has decoded the data into pixels, then the src buffer need not be

      *  copied. If the pixelref defers the actual decode until its lockPixels() is called, then it

      *  must make a copy of the src buffer.

      *  @param src Encoded data.

      *  @param length Size of the encoded data, in bytes.

      *  @param dst SkBitmap to install the pixel ref on.

      *  @param bool Whether or not a pixel ref was successfully installed.

      */

     typedef bool (*InstallPixelRefProc)(const void* src, size_t length, SkBitmap* dst);

     /**

      *  Recreate a picture that was serialized into a stream.

      *  @param SkStream Serialized picture data.

      *  @param proc Function pointer for installing pixelrefs on SkBitmaps representing the

      *              encoded bitmap data from the stream.

      *  @return A new SkPicture representing the serialized data, or NULL if the stream is

      *          invalid.

      */

     static SkPicture* CreateFromStream(SkStream*,

                                        InstallPixelRefProc proc = &SkImageDecoder::DecodeMemory);

     /**

      *  Recreate a picture that was serialized into a buffer. If the creation requires bitmap

      *  decoding, the decoder must be set on the SkReadBuffer parameter by calling

      *  SkReadBuffer::setBitmapDecoder() before calling SkPicture::CreateFromBuffer().

      *  @param SkReadBuffer Serialized picture data.

      *  @return A new SkPicture representing the serialized data, or NULL if the buffer is

      *          invalid.

      */

     static SkPicture* CreateFromBuffer(SkReadBuffer&);

     virtual ~SkPicture();

     /**

      *  Swap the contents of the two pictures. Guaranteed to succeed.

      */

     void swap(SkPicture& other);

     /**

      *  Creates a thread-safe clone of the picture that is ready for playback.

      */

     SkPicture* clone() const;

     /**

      * Creates multiple thread-safe clones of this picture that are ready for

      * playback. The resulting clones are stored in the provided array of

      * SkPictures.

      */

     void clone(SkPicture* pictures, int count) const;

     enum RecordingFlags {

         /*  This flag specifies that when clipPath() is called, the path will

             be faithfully recorded, but the recording canvas' current clip will

             only see the path's bounds. This speeds up the recording process

             without compromising the fidelity of the playback. The only side-

             effect for recording is that calling getTotalClip() or related

             clip-query calls will reflect the path's bounds, not the actual

             path.

          */

         kUsePathBoundsForClip_RecordingFlag = 0x01,

         /*  This flag causes the picture to compute bounding boxes and build

             up a spatial hierarchy (currently an R-Tree), plus a tree of Canvas'

             usually stack-based clip/etc state. This requires an increase in

             recording time (often ~2x; likely more for very complex pictures),

             but allows us to perform much faster culling at playback time, and

             completely avoid some unnecessary clips and other operations. This

             is ideal for tiled rendering, or any other situation where you're

             drawing a fraction of a large scene into a smaller viewport.

             In most cases the record cost is offset by the playback improvement

             after a frame or two of tiled rendering (and complex pictures that

             induce the worst record times will generally get the largest

             speedups at playback time).

             Note: Currently this is not serializable, the bounding data will be

             discarded if you serialize into a stream and then deserialize.

         */

         kOptimizeForClippedPlayback_RecordingFlag = 0x02,

     };

     /** Returns the canvas that records the drawing commands.

         @param width the base width for the picture, as if the recording

                      canvas' bitmap had this width.

         @param height the base width for the picture, as if the recording

                      canvas' bitmap had this height.

         @param recordFlags optional flags that control recording.

         @return the picture canvas.

     */

     SkCanvas* beginRecording(int width, int height, uint32_t recordFlags = 0);

     /** Returns the recording canvas if one is active, or NULL if recording is

         not active. This does not alter the refcnt on the canvas (if present).

     */

     SkCanvas* getRecordingCanvas() const;

     /** Signal that the caller is done recording. This invalidates the canvas

         returned by beginRecording/getRecordingCanvas, and prepares the picture

         for drawing. Note: this happens implicitly the first time the picture

         is drawn.

     */

     void endRecording();

     /** Replays the drawing commands on the specified canvas. This internally

         calls endRecording() if that has not already been called.

         @param canvas the canvas receiving the drawing commands.

     */

     void draw(SkCanvas* canvas, SkDrawPictureCallback* = NULL);

     /** Return the width of the picture's recording canvas. This

         value reflects what was passed to setSize(), and does not necessarily

         reflect the bounds of what has been recorded into the picture.

         @return the width of the picture's recording canvas

     */

     int width() const { return fWidth; }

     /** Return the height of the picture's recording canvas. This

         value reflects what was passed to setSize(), and does not necessarily

         reflect the bounds of what has been recorded into the picture.

         @return the height of the picture's recording canvas

     */

     int height() const { return fHeight; }

     /**

      *  Function to encode an SkBitmap to an SkData. A function with this

      *  signature can be passed to serialize() and SkWriteBuffer.

      *  Returning NULL will tell the SkWriteBuffer to use

      *  SkBitmap::flatten() to store the bitmap.

      *

      *  @param pixelRefOffset DEPRECATED -- caller assumes it will return 0.

      *  @return SkData If non-NULL, holds encoded data representing the passed

      *      in bitmap. The caller is responsible for calling unref().

      */

     typedef SkData* (*EncodeBitmap)(size_t* pixelRefOffset, const SkBitmap& bm);

     /**

      *  Serialize to a stream. If non NULL, encoder will be used to encode

      *  any bitmaps in the picture.

      *  encoder will never be called with a NULL pixelRefOffset.

      */

     void serialize(SkWStream*, EncodeBitmap encoder = NULL) const;

     /**

      *  Serialize to a buffer.

      */

     void flatten(SkWriteBuffer&) const;

     /**

      * Returns true if any bitmaps may be produced when this SkPicture

      * is replayed.

      * Returns false if called while still recording.

      */

     bool willPlayBackBitmaps() const;

 #ifdef SK_BUILD_FOR_ANDROID

     /** Signals that the caller is prematurely done replaying the drawing

         commands. This can be called from a canvas virtual while the picture

         is drawing. Has no effect if the picture is not drawing.

         @deprecated preserving for legacy purposes

     */

     void abortPlayback();

 #endif

     /** 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

         CreateFromStream or CreateFromBuffer. Note, CreateFromStream and

         CreateFromBuffer perform this check internally so these entry points are

         intended for stand alone tools.

         If false is returned, SkPictInfo is unmodified.

     */

     static bool InternalOnly_StreamIsSKP(SkStream*, SkPictInfo*);

     static bool InternalOnly_BufferIsSKP(SkReadBuffer&, SkPictInfo*);

     /** Enable/disable all the picture recording optimizations (i.e.,

         those in SkPictureRecord). It is mainly intended for testing the

         existing optimizations (i.e., to actually have the pattern

         appear in an .skp we have to disable the optimization). Call right

         after 'beginRecording'.

     */

     void internalOnly_EnableOpts(bool enableOpts);

 protected:

     // V2 : adds SkPixelRef's generation ID.

     // V3 : PictInfo tag at beginning, and EOF tag at the end

     // V4 : move SkPictInfo to be the header

     // V5 : don't read/write FunctionPtr on cross-process (we can detect that)

     // V6 : added serialization of SkPath's bounds (and packed its flags tighter)

     // V7 : changed drawBitmapRect(IRect) to drawBitmapRectToRect(Rect)

     // V8 : Add an option for encoding bitmaps

     // V9 : Allow the reader and writer of an SKP disagree on whether to support

     //      SK_SUPPORT_HINTING_SCALE_FACTOR

     // V10: add drawRRect, drawOval, clipRRect

     // V11: modify how readBitmap and writeBitmap store their info.

     // V12: add conics to SkPath, use new SkPathRef flattening

     // V13: add flag to drawBitmapRectToRect

     //      parameterize blurs by sigma rather than radius

     // V14: Add flags word to PathRef serialization

     // V15: Remove A1 bitmpa config (and renumber remaining configs)

     // V16: Move SkPath's isOval flag to SkPathRef

     // V17: SkPixelRef now writes SkImageInfo

     // V18: SkBitmap now records x,y for its pixelref origin, instead of offset.

     // V19: encode matrices and regions into the ops stream

     // V20: added bool to SkPictureImageFilter's serialization (to allow SkPicture serialization)

     // V21: add pushCull, popCull

     // V22: SK_PICT_FACTORY_TAG's size is now the chunk size in bytes

     // Note: If the picture version needs to be increased then please follow the

     // steps to generate new SKPs in (only accessible to Googlers): http://goo.gl/qATVcw

     // Only SKPs within the min/current picture version range (inclusive) can be read.

     static const uint32_t MIN_PICTURE_VERSION = 19;

     static const uint32_t CURRENT_PICTURE_VERSION = 22;

     // fPlayback, fRecord, fWidth & fHeight are protected to allow derived classes to

     // install their own SkPicturePlayback-derived players,SkPictureRecord-derived

     // recorders and set the picture size

     SkPicturePlayback*    fPlayback;

     SkPictureRecord*      fRecord;

     int                   fWidth, fHeight;

     const AccelData*      fAccelData;

     // Create a new SkPicture from an existing SkPicturePlayback. Ref count of

     // playback is unchanged.

     SkPicture(SkPicturePlayback*, int width, int height);

     // For testing. Derived classes may instantiate an alternate

     // SkBBoxHierarchy implementation

     virtual SkBBoxHierarchy* createBBoxHierarchy() const;

 private:

     void createHeader(SkPictInfo* info) const;

     static bool IsValidPictInfo(const SkPictInfo& info);

     friend class SkFlatPicture;

     friend class SkPicturePlayback;

     typedef SkRefCnt INHERITED;

 };

 /**

  *  Subclasses of this can be passed to canvas.drawPicture. During the drawing

  *  of the picture, this callback will periodically be invoked. If its

  *  abortDrawing() returns true, then picture playback will be interrupted.

  *

  *  The resulting drawing is undefined, as there is no guarantee how often the

  *  callback will be invoked. If the abort happens inside some level of nested

  *  calls to save(), restore will automatically be called to return the state

  *  to the same level it was before the drawPicture call was made.

  */

 class SK_API SkDrawPictureCallback {

 public:

     SkDrawPictureCallback() {}

     virtual ~SkDrawPictureCallback() {}

     virtual bool abortDrawing() = 0;

 };

 #endif