SkPicture.h revision 44d83c1e81b0555efa94f78e2a53b862208cdd06
1 2/* 3 * Copyright 2007 The Android Open Source Project 4 * 5 * Use of this source code is governed by a BSD-style license that can be 6 * found in the LICENSE file. 7 */ 8 9 10#ifndef SkPicture_DEFINED 11#define SkPicture_DEFINED 12 13#include "SkBitmap.h" 14#include "SkImageDecoder.h" 15#include "SkRefCnt.h" 16 17#if SK_SUPPORT_GPU 18class GrContext; 19#endif 20 21class SkBBHFactory; 22class SkBBoxHierarchy; 23class SkCanvas; 24class SkDrawPictureCallback; 25class SkData; 26class SkPicturePlayback; 27class SkPictureRecord; 28class SkStream; 29class SkWStream; 30 31struct SkPictInfo; 32 33/** \class SkPicture 34 35 The SkPicture class records the drawing commands made to a canvas, to 36 be played back at a later time. 37*/ 38class SK_API SkPicture : public SkRefCnt { 39public: 40 SK_DECLARE_INST_COUNT(SkPicture) 41 42 // AccelData provides a base class for device-specific acceleration 43 // data. It is added to the picture via a call to a device's optimize 44 // method. 45 class AccelData : public SkRefCnt { 46 public: 47 typedef uint8_t Domain; 48 typedef uint32_t Key; 49 50 AccelData(Key key) : fKey(key) { } 51 52 const Key& getKey() const { return fKey; } 53 54 // This entry point allows user's to get a unique domain prefix 55 // for their keys 56 static Domain GenerateDomain(); 57 private: 58 Key fKey; 59 60 typedef SkRefCnt INHERITED; 61 }; 62 63 SkPicture(); 64 /** Make a copy of the contents of src. If src records more drawing after 65 this call, those elements will not appear in this picture. 66 */ 67 SkPicture(const SkPicture& src); 68 69 /** PRIVATE / EXPERIMENTAL -- do not call */ 70 void EXPERIMENTAL_addAccelData(const AccelData* data) { 71 SkRefCnt_SafeAssign(fAccelData, data); 72 } 73 /** PRIVATE / EXPERIMENTAL -- do not call */ 74 const AccelData* EXPERIMENTAL_getAccelData(AccelData::Key key) const { 75 if (NULL != fAccelData && fAccelData->getKey() == key) { 76 return fAccelData; 77 } 78 return NULL; 79 } 80 81 /** 82 * Function signature defining a function that sets up an SkBitmap from encoded data. On 83 * success, the SkBitmap should have its Config, width, height, rowBytes and pixelref set. 84 * If the installed pixelref has decoded the data into pixels, then the src buffer need not be 85 * copied. If the pixelref defers the actual decode until its lockPixels() is called, then it 86 * must make a copy of the src buffer. 87 * @param src Encoded data. 88 * @param length Size of the encoded data, in bytes. 89 * @param dst SkBitmap to install the pixel ref on. 90 * @param bool Whether or not a pixel ref was successfully installed. 91 */ 92 typedef bool (*InstallPixelRefProc)(const void* src, size_t length, SkBitmap* dst); 93 94 /** 95 * Recreate a picture that was serialized into a stream. 96 * @param SkStream Serialized picture data. 97 * @param proc Function pointer for installing pixelrefs on SkBitmaps representing the 98 * encoded bitmap data from the stream. 99 * @return A new SkPicture representing the serialized data, or NULL if the stream is 100 * invalid. 101 */ 102 static SkPicture* CreateFromStream(SkStream*, 103 InstallPixelRefProc proc = &SkImageDecoder::DecodeMemory); 104 105 /** 106 * Recreate a picture that was serialized into a buffer. If the creation requires bitmap 107 * decoding, the decoder must be set on the SkReadBuffer parameter by calling 108 * SkReadBuffer::setBitmapDecoder() before calling SkPicture::CreateFromBuffer(). 109 * @param SkReadBuffer Serialized picture data. 110 * @return A new SkPicture representing the serialized data, or NULL if the buffer is 111 * invalid. 112 */ 113 static SkPicture* CreateFromBuffer(SkReadBuffer&); 114 115 virtual ~SkPicture(); 116 117 /** 118 * Swap the contents of the two pictures. Guaranteed to succeed. 119 */ 120 void swap(SkPicture& other); 121 122 /** 123 * Creates a thread-safe clone of the picture that is ready for playback. 124 */ 125 SkPicture* clone() const; 126 127 /** 128 * Creates multiple thread-safe clones of this picture that are ready for 129 * playback. The resulting clones are stored in the provided array of 130 * SkPictures. 131 */ 132 void clone(SkPicture* pictures, int count) const; 133 134 enum RecordingFlags { 135 /* This flag specifies that when clipPath() is called, the path will 136 be faithfully recorded, but the recording canvas' current clip will 137 only see the path's bounds. This speeds up the recording process 138 without compromising the fidelity of the playback. The only side- 139 effect for recording is that calling getTotalClip() or related 140 clip-query calls will reflect the path's bounds, not the actual 141 path. 142 */ 143 kUsePathBoundsForClip_RecordingFlag = 0x01 144 }; 145 146#ifndef SK_SUPPORT_DEPRECATED_RECORD_FLAGS 147 // TODO: once kOptimizeForClippedPlayback_RecordingFlag is hidden from 148 // all external consumers, SkPicture::createBBoxHierarchy can also be 149 // cleaned up. 150private: 151#endif 152 enum Deprecated_RecordingFlags { 153 /* This flag causes the picture to compute bounding boxes and build 154 up a spatial hierarchy (currently an R-Tree), plus a tree of Canvas' 155 usually stack-based clip/etc state. This requires an increase in 156 recording time (often ~2x; likely more for very complex pictures), 157 but allows us to perform much faster culling at playback time, and 158 completely avoid some unnecessary clips and other operations. This 159 is ideal for tiled rendering, or any other situation where you're 160 drawing a fraction of a large scene into a smaller viewport. 161 162 In most cases the record cost is offset by the playback improvement 163 after a frame or two of tiled rendering (and complex pictures that 164 induce the worst record times will generally get the largest 165 speedups at playback time). 166 167 Note: Currently this is not serializable, the bounding data will be 168 discarded if you serialize into a stream and then deserialize. 169 */ 170 kOptimizeForClippedPlayback_RecordingFlag = 0x02, 171 }; 172#ifndef SK_SUPPORT_DEPRECATED_RECORD_FLAGS 173public: 174#endif 175 176#ifndef SK_SUPPORT_LEGACY_PICTURE_CAN_RECORD 177private: 178#endif 179 180#ifdef SK_SUPPORT_LEGACY_DERIVED_PICTURE_CLASSES 181 182 /** Returns the canvas that records the drawing commands. 183 @param width the base width for the picture, as if the recording 184 canvas' bitmap had this width. 185 @param height the base width for the picture, as if the recording 186 canvas' bitmap had this height. 187 @param recordFlags optional flags that control recording. 188 @return the picture canvas. 189 */ 190 SkCanvas* beginRecording(int width, int height, uint32_t recordFlags = 0); 191#endif 192 193 /** Returns the recording canvas if one is active, or NULL if recording is 194 not active. This does not alter the refcnt on the canvas (if present). 195 */ 196 SkCanvas* getRecordingCanvas() const; 197 /** Signal that the caller is done recording. This invalidates the canvas 198 returned by beginRecording/getRecordingCanvas, and prepares the picture 199 for drawing. Note: this happens implicitly the first time the picture 200 is drawn. 201 */ 202 void endRecording(); 203 204#ifndef SK_SUPPORT_LEGACY_PICTURE_CAN_RECORD 205public: 206#endif 207 208 /** Replays the drawing commands on the specified canvas. This internally 209 calls endRecording() if that has not already been called. 210 @param canvas the canvas receiving the drawing commands. 211 */ 212 void draw(SkCanvas* canvas, SkDrawPictureCallback* = NULL); 213 214 /** Return the width of the picture's recording canvas. This 215 value reflects what was passed to setSize(), and does not necessarily 216 reflect the bounds of what has been recorded into the picture. 217 @return the width of the picture's recording canvas 218 */ 219 int width() const { return fWidth; } 220 221 /** Return the height of the picture's recording canvas. This 222 value reflects what was passed to setSize(), and does not necessarily 223 reflect the bounds of what has been recorded into the picture. 224 @return the height of the picture's recording canvas 225 */ 226 int height() const { return fHeight; } 227 228 /** Return a non-zero, unique value representing the picture. This call is 229 only valid when not recording. Between a beginRecording/endRecording 230 pair it will just return 0 (the invalid ID). Each beginRecording/ 231 endRecording pair will cause a different generation ID to be returned. 232 */ 233 uint32_t uniqueID() const; 234 235 /** 236 * Function to encode an SkBitmap to an SkData. A function with this 237 * signature can be passed to serialize() and SkWriteBuffer. 238 * Returning NULL will tell the SkWriteBuffer to use 239 * SkBitmap::flatten() to store the bitmap. 240 * 241 * @param pixelRefOffset DEPRECATED -- caller assumes it will return 0. 242 * @return SkData If non-NULL, holds encoded data representing the passed 243 * in bitmap. The caller is responsible for calling unref(). 244 */ 245 typedef SkData* (*EncodeBitmap)(size_t* pixelRefOffset, const SkBitmap& bm); 246 247 /** 248 * Serialize to a stream. If non NULL, encoder will be used to encode 249 * any bitmaps in the picture. 250 * encoder will never be called with a NULL pixelRefOffset. 251 */ 252 void serialize(SkWStream*, EncodeBitmap encoder = NULL) const; 253 254 /** 255 * Serialize to a buffer. 256 */ 257 void flatten(SkWriteBuffer&) const; 258 259 /** 260 * Returns true if any bitmaps may be produced when this SkPicture 261 * is replayed. 262 * Returns false if called while still recording. 263 */ 264 bool willPlayBackBitmaps() const; 265 266#ifdef SK_BUILD_FOR_ANDROID 267 /** Signals that the caller is prematurely done replaying the drawing 268 commands. This can be called from a canvas virtual while the picture 269 is drawing. Has no effect if the picture is not drawing. 270 @deprecated preserving for legacy purposes 271 */ 272 void abortPlayback(); 273#endif 274 275 /** Return true if the SkStream/Buffer represents a serialized picture, and 276 fills out SkPictInfo. After this function returns, the data source is not 277 rewound so it will have to be manually reset before passing to 278 CreateFromStream or CreateFromBuffer. Note, CreateFromStream and 279 CreateFromBuffer perform this check internally so these entry points are 280 intended for stand alone tools. 281 If false is returned, SkPictInfo is unmodified. 282 */ 283 static bool InternalOnly_StreamIsSKP(SkStream*, SkPictInfo*); 284 static bool InternalOnly_BufferIsSKP(SkReadBuffer&, SkPictInfo*); 285 286 /** Enable/disable all the picture recording optimizations (i.e., 287 those in SkPictureRecord). It is mainly intended for testing the 288 existing optimizations (i.e., to actually have the pattern 289 appear in an .skp we have to disable the optimization). Call right 290 after 'beginRecording'. 291 */ 292 void internalOnly_EnableOpts(bool enableOpts); 293 294 /** Return true if the picture is suitable for rendering on the GPU. 295 */ 296 297#if SK_SUPPORT_GPU 298 bool suitableForGpuRasterization(GrContext*) const; 299#endif 300 301protected: 302 // V2 : adds SkPixelRef's generation ID. 303 // V3 : PictInfo tag at beginning, and EOF tag at the end 304 // V4 : move SkPictInfo to be the header 305 // V5 : don't read/write FunctionPtr on cross-process (we can detect that) 306 // V6 : added serialization of SkPath's bounds (and packed its flags tighter) 307 // V7 : changed drawBitmapRect(IRect) to drawBitmapRectToRect(Rect) 308 // V8 : Add an option for encoding bitmaps 309 // V9 : Allow the reader and writer of an SKP disagree on whether to support 310 // SK_SUPPORT_HINTING_SCALE_FACTOR 311 // V10: add drawRRect, drawOval, clipRRect 312 // V11: modify how readBitmap and writeBitmap store their info. 313 // V12: add conics to SkPath, use new SkPathRef flattening 314 // V13: add flag to drawBitmapRectToRect 315 // parameterize blurs by sigma rather than radius 316 // V14: Add flags word to PathRef serialization 317 // V15: Remove A1 bitmap config (and renumber remaining configs) 318 // V16: Move SkPath's isOval flag to SkPathRef 319 // V17: SkPixelRef now writes SkImageInfo 320 // V18: SkBitmap now records x,y for its pixelref origin, instead of offset. 321 // V19: encode matrices and regions into the ops stream 322 // V20: added bool to SkPictureImageFilter's serialization (to allow SkPicture serialization) 323 // V21: add pushCull, popCull 324 // V22: SK_PICT_FACTORY_TAG's size is now the chunk size in bytes 325 // V23: SkPaint::FilterLevel became a real enum 326 // V24: SkTwoPointConicalGradient now has fFlipped flag for gradient flipping 327 328 // Note: If the picture version needs to be increased then please follow the 329 // steps to generate new SKPs in (only accessible to Googlers): http://goo.gl/qATVcw 330 331 // Only SKPs within the min/current picture version range (inclusive) can be read. 332 static const uint32_t MIN_PICTURE_VERSION = 19; 333 static const uint32_t CURRENT_PICTURE_VERSION = 24; 334 335 mutable uint32_t fUniqueID; 336 337 // fPlayback, fRecord, fWidth & fHeight are protected to allow derived classes to 338 // install their own SkPicturePlayback-derived players,SkPictureRecord-derived 339 // recorders and set the picture size 340 SkPicturePlayback* fPlayback; 341 SkPictureRecord* fRecord; 342 int fWidth, fHeight; 343 const AccelData* fAccelData; 344 345 void needsNewGenID() { fUniqueID = SK_InvalidGenID; } 346 347 // Create a new SkPicture from an existing SkPicturePlayback. Ref count of 348 // playback is unchanged. 349 SkPicture(SkPicturePlayback*, int width, int height); 350 351#ifdef SK_SUPPORT_LEGACY_DERIVED_PICTURE_CLASSES 352 // For testing. Derived classes may instantiate an alternate 353 // SkBBoxHierarchy implementation 354 virtual SkBBoxHierarchy* createBBoxHierarchy() const; 355#endif 356 357 SkCanvas* beginRecording(int width, int height, SkBBHFactory* factory, uint32_t recordFlags); 358 359private: 360 // An OperationList encapsulates a set of operation offsets into the picture byte 361 // stream along with the CTMs needed for those operation. 362 class OperationList : ::SkNoncopyable { 363 public: 364 virtual ~OperationList() {} 365 366 // If valid returns false then there is no optimization data 367 // present. All the draw operations need to be issued. 368 virtual bool valid() const { return false; } 369 370 // The following three entry points should only be accessed if 371 // 'valid' returns true. 372 virtual int numOps() const { SkASSERT(false); return 0; }; 373 // The offset in the picture of the operation to execute. 374 virtual uint32_t offset(int index) const { SkASSERT(false); return 0; }; 375 // The CTM that must be installed for the operation to behave correctly 376 virtual const SkMatrix& matrix(int index) const { SkASSERT(false); return SkMatrix::I(); } 377 378 static const OperationList& InvalidList(); 379 }; 380 381 /** PRIVATE / EXPERIMENTAL -- do not call 382 Return the operations required to render the content inside 'queryRect'. 383 */ 384 const OperationList& EXPERIMENTAL_getActiveOps(const SkIRect& queryRect); 385 386 /** PRIVATE / EXPERIMENTAL -- do not call 387 Return the ID of the operation currently being executed when playing 388 back. 0 indicates no call is active. 389 */ 390 size_t EXPERIMENTAL_curOpID() const; 391 392 void createHeader(SkPictInfo* info) const; 393 static bool IsValidPictInfo(const SkPictInfo& info); 394 395 friend class SkFlatPicture; 396 friend class SkPicturePlayback; 397 friend class SkPictureRecorder; 398 friend class SkGpuDevice; 399 friend class GrGatherDevice; 400 friend class SkDebugCanvas; 401 402 typedef SkRefCnt INHERITED; 403}; 404 405/** 406 * Subclasses of this can be passed to canvas.drawPicture. During the drawing 407 * of the picture, this callback will periodically be invoked. If its 408 * abortDrawing() returns true, then picture playback will be interrupted. 409 * 410 * The resulting drawing is undefined, as there is no guarantee how often the 411 * callback will be invoked. If the abort happens inside some level of nested 412 * calls to save(), restore will automatically be called to return the state 413 * to the same level it was before the drawPicture call was made. 414 */ 415class SK_API SkDrawPictureCallback { 416public: 417 SkDrawPictureCallback() {} 418 virtual ~SkDrawPictureCallback() {} 419 420 virtual bool abortDrawing() = 0; 421}; 422 423#ifdef SK_SUPPORT_LEGACY_DERIVED_PICTURE_CLASSES 424 425class SkPictureFactory : public SkRefCnt { 426public: 427 /** 428 * Allocate a new SkPicture. Return NULL on failure. 429 */ 430 virtual SkPicture* create(int width, int height) = 0; 431 432private: 433 typedef SkRefCnt INHERITED; 434}; 435 436#endif 437 438#ifdef SK_SUPPORT_LEGACY_PICTURE_HEADERS 439#include "SkPictureRecorder.h" 440#endif 441 442#endif 443