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
19class SkBitmap;
20class SkPDFCatalog;
21struct 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.
31class SkPDFImage : public SkPDFStream {
32public:
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
60private:
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