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      1 
      2 /*
      3  * Copyright 2010 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 SkPDFImage_DEFINED
     11 #define SkPDFImage_DEFINED
     12 
     13 #include "SkPicture.h"
     14 #include "SkPDFDevice.h"
     15 #include "SkPDFStream.h"
     16 #include "SkPDFTypes.h"
     17 #include "SkRefCnt.h"
     18 
     19 class SkBitmap;
     20 class SkPDFCatalog;
     21 struct SkIRect;
     22 
     23 /** \class SkPDFImage
     24 
     25     An image XObject.
     26 */
     27 
     28 // We could play the same trick here as is done in SkPDFGraphicState, storing
     29 // a copy of the Bitmap object (not the pixels), the pixel generation number,
     30 // and settings used from the paint to canonicalize image objects.
     31 class SkPDFImage : public SkPDFStream {
     32 public:
     33     /** Create a new Image XObject to represent the passed bitmap.
     34      *  @param bitmap   The image to encode.
     35      *  @param srcRect  The rectangle to cut out of bitmap.
     36      *  @param paint    Used to calculate alpha, masks, etc.
     37      *  @return  The image XObject or NUll if there is nothing to draw for
     38      *           the given parameters.
     39      */
     40     static SkPDFImage* CreateImage(const SkBitmap& bitmap,
     41                                    const SkIRect& srcRect,
     42                                    SkPicture::EncodeBitmap encoder);
     43 
     44     virtual ~SkPDFImage();
     45 
     46     /** Add a Soft Mask (alpha or shape channel) to the image.  Refs mask.
     47      *  @param mask A gray scale image representing the mask.
     48      *  @return The mask argument is returned.
     49      */
     50     SkPDFImage* addSMask(SkPDFImage* mask);
     51 
     52     bool isEmpty() {
     53         return fSrcRect.isEmpty();
     54     }
     55 
     56     // The SkPDFObject interface.
     57     virtual void getResources(const SkTSet<SkPDFObject*>& knownResourceObjects,
     58                               SkTSet<SkPDFObject*>* newResourceObjects);
     59 
     60 private:
     61     SkBitmap fBitmap;
     62     bool fIsAlpha;
     63     SkIRect fSrcRect;
     64     SkPicture::EncodeBitmap fEncoder;
     65     bool fStreamValid;
     66 
     67     SkTDArray<SkPDFObject*> fResources;
     68 
     69     /** Create a PDF image XObject. Entries for the image properties are
     70      *  automatically added to the stream dictionary.
     71      *  @param stream     The image stream. May be NULL. Otherwise, this
     72      *                    (instead of the input bitmap) will be used as the
     73      *                    PDF's content stream, possibly with lossless encoding.
     74      *  @param bitmap     The image. If a stream is not given, its color data
     75      *                    will be used as the image. If a stream is given, this
     76      *                    is used for configuration only.
     77      *  @param isAlpha    Whether or not this is the alpha of an image.
     78      *  @param srcRect    The clipping applied to bitmap before generating
     79      *                    imageData.
     80      *  @param encoder    A function used to encode the bitmap for compression.
     81      *                    May be NULL.
     82      */
     83     SkPDFImage(SkStream* stream, const SkBitmap& bitmap, bool isAlpha,
     84                const SkIRect& srcRect, SkPicture::EncodeBitmap encoder);
     85 
     86     /** Copy constructor, used to generate substitutes.
     87      *  @param image      The SkPDFImage to copy.
     88      */
     89     SkPDFImage(SkPDFImage& pdfImage);
     90 
     91     // Populate the stream dictionary.  This method returns false if
     92     // fSubstitute should be used.
     93     virtual bool populate(SkPDFCatalog* catalog);
     94 
     95     typedef SkPDFStream INHERITED;
     96 };
     97 
     98 #endif
     99