1
2/*
3 * Copyright 2011 Google Inc.
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#ifndef SkPathHeap_DEFINED
9#define SkPathHeap_DEFINED
10
11#include "SkRefCnt.h"
12#include "SkChunkAlloc.h"
13#include "SkTDArray.h"
14
15class SkPath;
16class SkReadBuffer;
17class SkWriteBuffer;
18
19class SkPathHeap : public SkRefCnt {
20public:
21    SK_DECLARE_INST_COUNT(SkPathHeap)
22
23    SkPathHeap();
24    SkPathHeap(SkReadBuffer&);
25    virtual ~SkPathHeap();
26
27    /** Copy the path into the heap, and return the new total number of paths.
28        Thus, the returned value will be index+1, where index is the index of
29        this newly added (copied) path.
30     */
31    int append(const SkPath&);
32
33    /** Add the specified path to the heap using its gen ID to de-duplicate.
34        Returns the path's index in the heap + 1.
35     */
36    int insert(const SkPath&);
37
38    // called during picture-playback
39    int count() const { return fPaths.count(); }
40    const SkPath& operator[](int index) const {
41        return *fPaths[index];
42    }
43
44    void flatten(SkWriteBuffer&) const;
45
46private:
47    // we store the paths in the heap (placement new)
48    SkChunkAlloc        fHeap;
49    // we just store ptrs into fHeap here
50    SkTDArray<SkPath*>  fPaths;
51
52    class LookupEntry {
53    public:
54        LookupEntry(const SkPath& path);
55
56        int storageSlot() const { return fStorageSlot; }
57        void setStorageSlot(int storageSlot) { fStorageSlot = storageSlot; }
58
59        static bool Less(const LookupEntry& a, const LookupEntry& b) {
60            return a.fGenerationID < b.fGenerationID;
61        }
62
63    private:
64        uint32_t fGenerationID;     // the SkPath's generation ID
65        // the path's index in the heap + 1. It is 0 if the path is not yet in the heap.
66        int      fStorageSlot;
67    };
68
69    SkTDArray<LookupEntry> fLookupTable;
70
71    SkPathHeap::LookupEntry* addIfNotPresent(const SkPath& path);
72
73    typedef SkRefCnt INHERITED;
74};
75
76#endif
77