• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright 2006 The Android Open Source Project
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 SkGraphics_DEFINED
9 #define SkGraphics_DEFINED
10 
11 #include "include/core/SkRefCnt.h"
12 
13 #include <memory>
14 
15 class SkData;
16 class SkImageGenerator;
17 class SkOpenTypeSVGDecoder;
18 class SkTraceMemoryDump;
19 
20 class SK_API SkGraphics {
21 public:
22     /**
23      *  Call this at process initialization time if your environment does not
24      *  permit static global initializers that execute code.
25      *  Init() is thread-safe and idempotent.
26      */
27     static void Init();
28 
29     /**
30      *  Return the max number of bytes that should be used by the font cache.
31      *  If the cache needs to allocate more, it will purge previous entries.
32      *  This max can be changed by calling SetFontCacheLimit().
33      */
34     static size_t GetFontCacheLimit();
35 
36     /**
37      *  Specify the max number of bytes that should be used by the font cache.
38      *  If the cache needs to allocate more, it will purge previous entries.
39      *
40      *  This function returns the previous setting, as if GetFontCacheLimit()
41      *  had be called before the new limit was set.
42      */
43     static size_t SetFontCacheLimit(size_t bytes);
44 
45     /**
46      *  Return the number of bytes currently used by the font cache.
47      */
48     static size_t GetFontCacheUsed();
49 
50     /**
51      *  Return the number of entries in the font cache.
52      *  A cache "entry" is associated with each typeface + pointSize + matrix.
53      */
54     static int GetFontCacheCountUsed();
55 
56     /**
57      *  Return the current limit to the number of entries in the font cache.
58      *  A cache "entry" is associated with each typeface + pointSize + matrix.
59      */
60     static int GetFontCacheCountLimit();
61 
62     /**
63      *  Set the limit to the number of entries in the font cache, and return
64      *  the previous value. If this new value is lower than the previous,
65      *  it will automatically try to purge entries to meet the new limit.
66      */
67     static int SetFontCacheCountLimit(int count);
68 
69     /**
70      *  For debugging purposes, this will attempt to purge the font cache. It
71      *  does not change the limit, but will cause subsequent font measures and
72      *  draws to be recreated, since they will no longer be in the cache.
73      */
74     static void PurgeFontCache();
75 
76     /**
77      *  This function returns the memory used for temporary images and other resources.
78      */
79     static size_t GetResourceCacheTotalBytesUsed();
80 
81     /**
82      *  These functions get/set the memory usage limit for the resource cache, used for temporary
83      *  bitmaps and other resources. Entries are purged from the cache when the memory useage
84      *  exceeds this limit.
85      */
86     static size_t GetResourceCacheTotalByteLimit();
87     static size_t SetResourceCacheTotalByteLimit(size_t newLimit);
88 
89     /**
90      *  For debugging purposes, this will attempt to purge the resource cache. It
91      *  does not change the limit.
92      */
93     static void PurgeResourceCache();
94 
95     /**
96      *  When the cachable entry is very lage (e.g. a large scaled bitmap), adding it to the cache
97      *  can cause most/all of the existing entries to be purged. To avoid the, the client can set
98      *  a limit for a single allocation. If a cacheable entry would have been cached, but its size
99      *  exceeds this limit, then we do not attempt to cache it at all.
100      *
101      *  Zero is the default value, meaning we always attempt to cache entries.
102      */
103     static size_t GetResourceCacheSingleAllocationByteLimit();
104     static size_t SetResourceCacheSingleAllocationByteLimit(size_t newLimit);
105 
106     /**
107      *  Dumps memory usage of caches using the SkTraceMemoryDump interface. See SkTraceMemoryDump
108      *  for usage of this method.
109      */
110     static void DumpMemoryStatistics(SkTraceMemoryDump* dump);
111 
112     /**
113      *  Free as much globally cached memory as possible. This will purge all private caches in Skia,
114      *  including font and image caches.
115      *
116      *  If there are caches associated with GPU context, those will not be affected by this call.
117      */
118     static void PurgeAllCaches();
119 
120     /**
121      *  Applications with command line options may pass optional state, such
122      *  as cache sizes, here, for instance:
123      *  font-cache-limit=12345678
124      *
125      *  The flags format is name=value[;name=value...] with no spaces.
126      *  This format is subject to change.
127      */
128     static void SetFlags(const char* flags);
129 
130     typedef std::unique_ptr<SkImageGenerator>
131                                             (*ImageGeneratorFromEncodedDataFactory)(sk_sp<SkData>);
132 
133     /**
134      *  To instantiate images from encoded data, first looks at this runtime function-ptr. If it
135      *  exists, it is called to create an SkImageGenerator from SkData. If there is no function-ptr
136      *  or there is, but it returns NULL, then skia will call its internal default implementation.
137      *
138      *  Returns the previous factory (which could be NULL).
139      */
140     static ImageGeneratorFromEncodedDataFactory
141                     SetImageGeneratorFromEncodedDataFactory(ImageGeneratorFromEncodedDataFactory);
142 
143     /**
144      *  To draw OpenType SVG data, Skia will look at this runtime function pointer. If this function
145      *  pointer is set, the SkTypeface implementations which support OpenType SVG will call this
146      *  function to create an SkOpenTypeSVGDecoder to decode the OpenType SVG and draw it as needed.
147      *  If this function is not set, the SkTypeface implementations will generally not support
148      *  OpenType SVG and attempt to use other glyph representations if available.
149      */
150     using OpenTypeSVGDecoderFactory =
151             std::unique_ptr<SkOpenTypeSVGDecoder> (*)(const uint8_t* svg, size_t length);
152     static OpenTypeSVGDecoderFactory SetOpenTypeSVGDecoderFactory(OpenTypeSVGDecoderFactory);
153     static OpenTypeSVGDecoderFactory GetOpenTypeSVGDecoderFactory();
154 
155     /**
156      *  Call early in main() to allow Skia to use a JIT to accelerate CPU-bound operations.
157      */
158     static void AllowJIT();
159 };
160 
161 class SkAutoGraphics {
162 public:
SkAutoGraphics()163     SkAutoGraphics() {
164         SkGraphics::Init();
165     }
166 };
167 
168 #endif
169