SkBitmapKey.h revision 895f3f0544ce38d35999771754cbb1d876c14b5a 
1/*
2 * Copyright 2016 Google Inc.
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#ifndef SkBitmapKey_DEFINED
8#define SkBitmapKey_DEFINED
9
10#include "SkBitmap.h"
11#include "SkImage.h"
12#include "SkCanvas.h"
13
14class SkBitmapKey {
15public:
16    SkBitmapKey() : fSubset(SkIRect::MakeEmpty()), fID(0) {}
17    explicit SkBitmapKey(const SkBitmap& bm)
18        : fSubset(bm.getSubset()), fID(bm.getGenerationID()) {}
19    explicit SkBitmapKey(const SkImage* img)
20        : fSubset(img ? img->bounds() : SkIRect::MakeEmpty())
21        , fID(img ? img->uniqueID() : 0) {}
22    explicit SkBitmapKey(const sk_sp<SkImage> img)
23        : fSubset(img->bounds()), fID(img->uniqueID()) {}
24    bool operator==(const SkBitmapKey& rhs) const {
25        return fID == rhs.fID && fSubset == rhs.fSubset;
26    }
27    bool operator!=(const SkBitmapKey& rhs) const { return !(*this == rhs); }
28    uint32_t id() const { return fID; }
29
30private:
31    SkIRect fSubset;
32    uint32_t fID;
33};
34
35/**
36   This wraps a thing that could either be a bitmap or a image and
37   abstracts out some common tasks.
38 */
39class SkImageBitmap {
40public:
41    explicit SkImageBitmap(const SkBitmap& b) : fBitmap(b), fImage(nullptr) {}
42    explicit SkImageBitmap(SkImage* i) : fImage(i) { SkASSERT(fImage); }
43    SkIRect bounds() const { return fImage ? fImage->bounds() : fBitmap.bounds(); }
44    SkISize dimensions() const {
45        return fImage ? fImage->dimensions() : fBitmap.dimensions();
46    }
47    sk_sp<SkImage> makeImage() const {
48        return fImage ? sk_ref_sp(fImage) : SkImage::MakeFromBitmap(fBitmap);
49    }
50    SkBitmapKey getKey() const {
51        return fImage ? SkBitmapKey(fImage) : SkBitmapKey(fBitmap);
52    }
53    void draw(SkCanvas* canvas, SkPaint* paint) const {
54        if (fImage) {
55            canvas->drawImage(fImage, 0, 0, paint);
56        } else {
57            canvas->drawBitmap(fBitmap, 0, 0, paint);
58        }
59    }
60
61private:
62    SkBitmap fBitmap;
63    SkImage* fImage; // non-owning; when drawImage starts passing a sk_sp<>,
64                     // we can take a const ref to that sk_sp<>.
65};
66
67#endif  // SkBitmapKey_DEFINED
68