1 /* 2 * Copyright 2007 The Android Open Source Project 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #ifndef SkPicture_DEFINED 9 #define SkPicture_DEFINED 10 11 #include "SkRefCnt.h" 12 #include "SkRect.h" 13 #include "SkTypes.h" 14 15 class SkBigPicture; 16 class SkCanvas; 17 class SkData; 18 struct SkDeserialProcs; 19 class SkImage; 20 class SkPictureData; 21 class SkReadBuffer; 22 class SkRefCntSet; 23 struct SkSerialProcs; 24 class SkStream; 25 class SkTypefacePlayback; 26 class SkWStream; 27 class SkWriteBuffer; 28 struct SkPictInfo; 29 30 /** \class SkPicture 31 32 An SkPicture records drawing commands made to a canvas to be played back at a later time. 33 This base class handles serialization and a few other miscellany. 34 */ 35 class SK_API SkPicture : public SkRefCnt { 36 public: 37 /** 38 * Recreate a picture that was serialized into a stream or data. 39 */ 40 41 static sk_sp<SkPicture> MakeFromStream(SkStream*, const SkDeserialProcs* = nullptr); 42 static sk_sp<SkPicture> MakeFromData(const SkData* data, const SkDeserialProcs* = nullptr); 43 static sk_sp<SkPicture> MakeFromData(const void* data, size_t size, 44 const SkDeserialProcs* = nullptr); 45 46 /** 47 * Recreate a picture that was serialized into a buffer. If the creation requires bitmap 48 * decoding, the decoder must be set on the SkReadBuffer parameter by calling 49 * SkReadBuffer::setBitmapDecoder() before calling SkPicture::MakeFromBuffer(). 50 * @param SkReadBuffer Serialized picture data. 51 * @return A new SkPicture representing the serialized data, or NULL if the buffer is 52 * invalid. 53 */ 54 static sk_sp<SkPicture> MakeFromBuffer(SkReadBuffer&); 55 56 /** 57 * Subclasses of this can be passed to playback(). During the playback 58 * of the picture, this callback will periodically be invoked. If its 59 * abort() returns true, then picture playback will be interrupted. 60 * 61 * The resulting drawing is undefined, as there is no guarantee how often the 62 * callback will be invoked. If the abort happens inside some level of nested 63 * calls to save(), restore will automatically be called to return the state 64 * to the same level it was before the playback call was made. 65 */ 66 class SK_API AbortCallback { 67 public: 68 AbortCallback() {} 69 virtual ~AbortCallback() {} 70 virtual bool abort() = 0; 71 }; 72 73 /** Replays the drawing commands on the specified canvas. Note that 74 this has the effect of unfurling this picture into the destination 75 canvas. Using the SkCanvas::drawPicture entry point gives the destination 76 canvas the option of just taking a ref. 77 @param canvas the canvas receiving the drawing commands. 78 @param callback a callback that allows interruption of playback 79 */ 80 virtual void playback(SkCanvas*, AbortCallback* = nullptr) const = 0; 81 82 /** Return a cull rect for this picture. 83 Ops recorded into this picture that attempt to draw outside the cull might not be drawn. 84 */ 85 virtual SkRect cullRect() const = 0; 86 87 /** Returns a non-zero value unique among all pictures. */ 88 uint32_t uniqueID() const; 89 90 sk_sp<SkData> serialize(const SkSerialProcs* = nullptr) const; 91 void serialize(SkWStream*, const SkSerialProcs* = nullptr) const; 92 93 /** 94 * Return a placeholder SkPicture. 95 * This placeholder does not draw anything itself. It has a distinct uniqueID() 96 * (just like all SkPictures) and will always be visible to SkSerialProcs. 97 * @param cull the placeholder's dimensions 98 */ 99 static sk_sp<SkPicture> MakePlaceholder(SkRect cull); 100 101 /** 102 * Serialize to a buffer. 103 */ 104 void flatten(SkWriteBuffer&) const; 105 106 /** Return the approximate number of operations in this picture. This 107 * number may be greater or less than the number of SkCanvas calls 108 * recorded: some calls may be recorded as more than one operation, or some 109 * calls may be optimized away. 110 */ 111 virtual int approximateOpCount() const = 0; 112 113 /** Returns the approximate byte size of this picture, not including large ref'd objects. */ 114 virtual size_t approximateBytesUsed() const = 0; 115 116 // Returns NULL if this is not an SkBigPicture. 117 virtual const SkBigPicture* asSkBigPicture() const { return nullptr; } 118 119 private: 120 // Subclass whitelist. 121 SkPicture(); 122 friend class SkBigPicture; 123 friend class SkEmptyPicture; 124 template <typename> friend class SkMiniPicture; 125 126 void serialize(SkWStream*, const SkSerialProcs*, SkRefCntSet* typefaces) const; 127 static sk_sp<SkPicture> MakeFromStream(SkStream*, const SkDeserialProcs*, SkTypefacePlayback*); 128 friend class SkPictureData; 129 130 /** Return true if the SkStream/Buffer represents a serialized picture, and 131 fills out SkPictInfo. After this function returns, the data source is not 132 rewound so it will have to be manually reset before passing to 133 MakeFromStream or MakeFromBuffer. Note, MakeFromStream and 134 MakeFromBuffer perform this check internally so these entry points are 135 intended for stand alone tools. 136 If false is returned, SkPictInfo is unmodified. 137 */ 138 static bool StreamIsSKP(SkStream*, SkPictInfo*); 139 static bool BufferIsSKP(SkReadBuffer*, SkPictInfo*); 140 friend bool SkPicture_StreamIsSKP(SkStream*, SkPictInfo*); 141 142 friend struct SkPathCounter; 143 144 // V35: Store SkRect (rather then width & height) in header 145 // V36: Remove (obsolete) alphatype from SkColorTable 146 // V37: Added shadow only option to SkDropShadowImageFilter (last version to record CLEAR) 147 // V38: Added PictureResolution option to SkPictureImageFilter 148 // V39: Added FilterLevel option to SkPictureImageFilter 149 // V40: Remove UniqueID serialization from SkImageFilter. 150 // V41: Added serialization of SkBitmapSource's filterQuality parameter 151 // V42: Added a bool to SkPictureShader serialization to indicate did-we-serialize-a-picture? 152 // V43: Added DRAW_IMAGE and DRAW_IMAGE_RECT opt codes to serialized data 153 // V44: Move annotations from paint to drawAnnotation 154 // V45: Add invNormRotation to SkLightingShader. 155 // V46: Add drawTextRSXform 156 // V47: Add occluder rect to SkBlurMaskFilter 157 // V48: Read and write extended SkTextBlobs. 158 // V49: Gradients serialized as SkColor4f + SkColorSpace 159 // V50: SkXfermode -> SkBlendMode 160 // V51: more SkXfermode -> SkBlendMode 161 // V52: Remove SkTextBlob::fRunCount 162 // V53: SaveLayerRec clip mask 163 // V54: ComposeShader can use a Mode or a Lerp 164 // V55: Drop blendmode[] from MergeImageFilter 165 // V56: Add TileMode in SkBlurImageFilter. 166 // V57: Sweep tiling info. 167 // V58: No more 2pt conical flipping. 168 // V59: No more LocalSpace option on PictureImageFilter 169 // V60: Remove flags in picture header 170 // V61: Change SkDrawPictureRec to take two colors rather than two alphas 171 172 // Only SKPs within the min/current picture version range (inclusive) can be read. 173 static const uint32_t MIN_PICTURE_VERSION = 56; // august 2017 174 static const uint32_t CURRENT_PICTURE_VERSION = 61; 175 176 static bool IsValidPictInfo(const SkPictInfo& info); 177 static sk_sp<SkPicture> Forwardport(const SkPictInfo&, 178 const SkPictureData*, 179 SkReadBuffer* buffer); 180 181 SkPictInfo createHeader() const; 182 SkPictureData* backport() const; 183 184 mutable uint32_t fUniqueID; 185 }; 186 187 #endif 188