1/*
2 * Copyright 2013 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
8#ifndef SkMipMap_DEFINED
9#define SkMipMap_DEFINED
10
11#include "SkCachedData.h"
12#include "SkPixmap.h"
13#include "SkScalar.h"
14#include "SkSize.h"
15
16class SkBitmap;
17class SkDiscardableMemory;
18
19typedef SkDiscardableMemory* (*SkDiscardableFactoryProc)(size_t bytes);
20
21class SkMipMap : public SkCachedData {
22public:
23    static SkMipMap* Build(const SkPixmap& src, SkDiscardableFactoryProc);
24    static SkMipMap* Build(const SkBitmap& src, SkDiscardableFactoryProc);
25
26    // This function lets you determine how many levels a SkMipMap will have without
27    // creating that mipmap.
28    static int ComputeLevelCount(int baseWidth, int baseHeight);
29
30    struct Level {
31        SkPixmap    fPixmap;
32        SkSize      fScale; // < 1.0
33    };
34
35    bool extractLevel(const SkSize& scale, Level*) const;
36    int countLevels() const;
37    bool getLevel(int index, Level*) const;
38
39protected:
40    void onDataChange(void* oldData, void* newData) override {
41        fLevels = (Level*)newData; // could be nullptr
42    }
43
44private:
45    Level*  fLevels;
46    int     fCount;
47
48    // we take ownership of levels, and will free it with sk_free()
49    SkMipMap(void* malloc, size_t size) : INHERITED(malloc, size) {}
50    SkMipMap(size_t size, SkDiscardableMemory* dm) : INHERITED(size, dm) {}
51
52    static size_t AllocLevelsSize(int levelCount, size_t pixelSize);
53
54    typedef SkCachedData INHERITED;
55};
56
57#endif
58