SkFontMgr.h revision d6bab0238655dbab24dfe92bd0b16b464310a8c7 
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 SkFontMgr_DEFINED
9#define SkFontMgr_DEFINED
10
11#include "SkRefCnt.h"
12#include "SkFontStyle.h"
13
14class SkData;
15class SkStream;
16class SkString;
17class SkTypeface;
18
19class SK_API SkFontStyleSet : public SkRefCnt {
20public:
21    SK_DECLARE_INST_COUNT(SkFontStyleSet)
22
23    virtual int count() = 0;
24    virtual void getStyle(int index, SkFontStyle*, SkString* style) = 0;
25    virtual SkTypeface* createTypeface(int index) = 0;
26    virtual SkTypeface* matchStyle(const SkFontStyle& pattern) = 0;
27
28    static SkFontStyleSet* CreateEmpty();
29
30private:
31    typedef SkRefCnt INHERITED;
32};
33
34class SkTypeface;
35
36class SK_API SkFontMgr : public SkRefCnt {
37public:
38    SK_DECLARE_INST_COUNT(SkFontMgr)
39
40    int countFamilies();
41    void getFamilyName(int index, SkString* familyName);
42    SkFontStyleSet* createStyleSet(int index);
43
44    /**
45     *  The caller must call unref() on the returned object.
46     *  Never returns NULL; will return an empty set if the name is not found.
47     */
48    SkFontStyleSet* matchFamily(const char familyName[]);
49
50    /**
51     *  Find the closest matching typeface to the specified familyName and style
52     *  and return a ref to it. The caller must call unref() on the returned
53     *  object. Will never return NULL, as it will return the default font if
54     *  no matching font is found.
55     */
56    SkTypeface* matchFamilyStyle(const char familyName[], const SkFontStyle&);
57
58    SkTypeface* matchFaceStyle(const SkTypeface*, const SkFontStyle&);
59
60    /**
61     *  Create a typeface for the specified data and TTC index (pass 0 for none)
62     *  or NULL if the data is not recognized. The caller must call unref() on
63     *  the returned object if it is not null.
64     */
65    SkTypeface* createFromData(SkData*, int ttcIndex = 0);
66
67    /**
68     *  Create a typeface for the specified stream and TTC index
69     *  (pass 0 for none) or NULL if the stream is not recognized. The caller
70     *  must call unref() on the returned object if it is not null.
71     */
72    SkTypeface* createFromStream(SkStream*, int ttcIndex = 0);
73
74    /**
75     *  Create a typeface for the specified fileName and TTC index
76     *  (pass 0 for none) or NULL if the file is not found, or its contents are
77     *  not recognized. The caller must call unref() on the returned object
78     *  if it is not null.
79     */
80    SkTypeface* createFromFile(const char path[], int ttcIndex = 0);
81
82    SkTypeface* legacyCreateTypeface(const char familyName[],
83                                     unsigned typefaceStyleBits);
84
85    /**
86     *  Return a ref to the default fontmgr. The caller must call unref() on
87     *  the returned object.
88     */
89    static SkFontMgr* RefDefault();
90
91protected:
92    virtual int onCountFamilies() = 0;
93    virtual void onGetFamilyName(int index, SkString* familyName) = 0;
94    virtual SkFontStyleSet* onCreateStyleSet(int index) = 0;
95
96    /** May return NULL if the name is not found. */
97    virtual SkFontStyleSet* onMatchFamily(const char familyName[]) = 0;
98
99    virtual SkTypeface* onMatchFamilyStyle(const char familyName[],
100                                           const SkFontStyle&) = 0;
101    virtual SkTypeface* onMatchFaceStyle(const SkTypeface*,
102                                         const SkFontStyle&) = 0;
103
104    virtual SkTypeface* onCreateFromData(SkData*, int ttcIndex) = 0;
105    virtual SkTypeface* onCreateFromStream(SkStream*, int ttcIndex) = 0;
106    virtual SkTypeface* onCreateFromFile(const char path[], int ttcIndex) = 0;
107
108    virtual SkTypeface* onLegacyCreateTypeface(const char familyName[],
109                                               unsigned styleBits) = 0;
110private:
111    static SkFontMgr* Factory();    // implemented by porting layer
112    friend void set_up_default(SkFontMgr** singleton);
113
114    typedef SkRefCnt INHERITED;
115};
116
117#endif
118