SkBitmapKey.h revision a50151dcb5a0b8bfdef383e363e519c91d2d2c7a 
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
29private:
30    SkIRect fSubset;
31    uint32_t fID;
32};
33
34/**
35   This wraps a thing that could either be a bitmap or a image and
36   abstracts out some common tasks.
37 */
38class SkImageBitmap {
39public:
40    explicit SkImageBitmap(const SkBitmap& b) : fBitmap(b), fImage(nullptr) {}
41    explicit SkImageBitmap(SkImage* i) : fImage(i) { SkASSERT(fImage); }
42    SkIRect bounds() const { return fImage ? fImage->bounds() : fBitmap.bounds(); }
43    SkISize dimensions() const {
44        return fImage ? fImage->dimensions() : fBitmap.dimensions();
45    }
46    sk_sp<SkImage> makeImage() const {
47        return fImage ? sk_ref_sp(fImage) : SkImage::MakeFromBitmap(fBitmap);
48    }
49    SkBitmapKey getKey() const {
50        return fImage ? SkBitmapKey(fImage) : SkBitmapKey(fBitmap);
51    }
52    void draw(SkCanvas* canvas, SkPaint* paint) const {
53        if (fImage) {
54            canvas->drawImage(fImage, 0, 0, paint);
55        } else {
56            canvas->drawBitmap(fBitmap, 0, 0, paint);
57        }
58    }
59
60private:
61    SkBitmap fBitmap;
62    SkImage* fImage; // non-owning; when drawImage starts passing a sk_sp<>,
63                     // we can take a const ref to that sk_sp<>.
64};
65
66#endif  // SkBitmapKey_DEFINED
67