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
13class SkData;
14class SkImageGenerator;
15class SkTraceMemoryDump;
16
17class SK_API SkGraphics {
18public:
19 /**
20 * Call this at process initialization time if your environment does not
21 * permit static global initializers that execute code.
22 * Init() is thread-safe and idempotent.
23 */
24 static void Init();
25
26 // We're in the middle of cleaning this up.
27 static void Term() {}
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 * Returns the maximum point size for text that may be cached.
71 *
72 * Sizes above this will be drawn directly from the font's outline.
73 * Setting this to a large value may speed up drawing larger text (repeatedly),
74 * but could cause the cache to purge other sizes more often.
75 *
76 * This value is a hint to the font engine, and the actual limit may be different due to
77 * implementation specific details.
78 */
79 static int GetFontCachePointSizeLimit();
80
81 /*
82 * Set the maximum point size for text that may be cached, returning the previous value.
83 *
84 * Sizes above this will be drawn directly from the font's outline.
85 * Setting this to a large value may speed up drawing larger text (repeatedly),
86 * but could cause the cache to purge other sizes more often.
87 *
88 * This value is a hint to the font engine, and the actual limit may be different due to
89 * implementation specific details.
90 */
91 static int SetFontCachePointSizeLimit(int maxPointSize);
92
93 /**
94 * For debugging purposes, this will attempt to purge the font cache. It
95 * does not change the limit, but will cause subsequent font measures and
96 * draws to be recreated, since they will no longer be in the cache.
97 */
98 static void PurgeFontCache();
99
100 /**
101 * Scaling bitmaps with the kHigh_SkFilterQuality setting is
102 * expensive, so the result is saved in the global Scaled Image
103 * Cache.
104 *
105 * This function returns the memory usage of the Scaled Image Cache.
106 */
107 static size_t GetResourceCacheTotalBytesUsed();
108
109 /**
110 * These functions get/set the memory usage limit for the resource cache, used for temporary
111 * bitmaps and other resources. Entries are purged from the cache when the memory useage
112 * exceeds this limit.
113 */
114 static size_t GetResourceCacheTotalByteLimit();
115 static size_t SetResourceCacheTotalByteLimit(size_t newLimit);
116
117 /**
118 * For debugging purposes, this will attempt to purge the resource cache. It
119 * does not change the limit.
120 */
121 static void PurgeResourceCache();
122
123 /**
124 * When the cachable entry is very lage (e.g. a large scaled bitmap), adding it to the cache
125 * can cause most/all of the existing entries to be purged. To avoid the, the client can set
126 * a limit for a single allocation. If a cacheable entry would have been cached, but its size
127 * exceeds this limit, then we do not attempt to cache it at all.
128 *
129 * Zero is the default value, meaning we always attempt to cache entries.
130 */
131 static size_t GetResourceCacheSingleAllocationByteLimit();
132 static size_t SetResourceCacheSingleAllocationByteLimit(size_t newLimit);
133
134 /**
135 * Dumps memory usage of caches using the SkTraceMemoryDump interface. See SkTraceMemoryDump
136 * for usage of this method.
137 */
138 static void DumpMemoryStatistics(SkTraceMemoryDump* dump);
139
140 /**
141 * Free as much globally cached memory as possible. This will purge all private caches in Skia,
142 * including font and image caches.
143 *
144 * If there are caches associated with GPU context, those will not be affected by this call.
145 */
146 static void PurgeAllCaches();
147
148 /**
149 * Applications with command line options may pass optional state, such
150 * as cache sizes, here, for instance:
151 * font-cache-limit=12345678
152 *
153 * The flags format is name=value[;name=value...] with no spaces.
154 * This format is subject to change.
155 */
156 static void SetFlags(const char* flags);
157
158 typedef std::unique_ptr<SkImageGenerator>
159 (*ImageGeneratorFromEncodedDataFactory)(sk_sp<SkData>);
160
161 /**
162 * To instantiate images from encoded data, first looks at this runtime function-ptr. If it
163 * exists, it is called to create an SkImageGenerator from SkData. If there is no function-ptr
164 * or there is, but it returns NULL, then skia will call its internal default implementation.
165 *
166 * Returns the previous factory (which could be NULL).
167 */
168 static ImageGeneratorFromEncodedDataFactory
169 SetImageGeneratorFromEncodedDataFactory(ImageGeneratorFromEncodedDataFactory);
170
171 /**
172 * Call early in main() to allow Skia to use a JIT to accelerate CPU-bound operations.
173 */
174 static void AllowJIT();
175};
176
177class SkAutoGraphics {
178public:
179 SkAutoGraphics() {
180 SkGraphics::Init();
181 }
182};
183
184#endif
185