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 "SkRefCnt.h" 12 13 class SkData; 14 class SkImageGenerator; 15 class SkTraceMemoryDump; 16 17 class SK_API SkGraphics { 18 public: 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 version numbers for the library. If the parameter is not 31 * null, it is set to the version number. 32 */ 33 static void GetVersion(int32_t* major, int32_t* minor, int32_t* patch); 34 35 /** 36 * Return the max number of bytes that should be used by the font cache. 37 * If the cache needs to allocate more, it will purge previous entries. 38 * This max can be changed by calling SetFontCacheLimit(). 39 */ 40 static size_t GetFontCacheLimit(); 41 42 /** 43 * Specify the max number of bytes that should be used by the font cache. 44 * If the cache needs to allocate more, it will purge previous entries. 45 * 46 * This function returns the previous setting, as if GetFontCacheLimit() 47 * had be called before the new limit was set. 48 */ 49 static size_t SetFontCacheLimit(size_t bytes); 50 51 /** 52 * Return the number of bytes currently used by the font cache. 53 */ 54 static size_t GetFontCacheUsed(); 55 56 /** 57 * Return the number of entries in the font cache. 58 * A cache "entry" is associated with each typeface + pointSize + matrix. 59 */ 60 static int GetFontCacheCountUsed(); 61 62 /** 63 * Return the current limit to the number of entries in the font cache. 64 * A cache "entry" is associated with each typeface + pointSize + matrix. 65 */ 66 static int GetFontCacheCountLimit(); 67 68 /** 69 * Set the limit to the number of entries in the font cache, and return 70 * the previous value. If this new value is lower than the previous, 71 * it will automatically try to purge entries to meet the new limit. 72 */ 73 static int SetFontCacheCountLimit(int count); 74 75 /** 76 * For debugging purposes, this will attempt to purge the font cache. It 77 * does not change the limit, but will cause subsequent font measures and 78 * draws to be recreated, since they will no longer be in the cache. 79 */ 80 static void PurgeFontCache(); 81 82 /** 83 * Scaling bitmaps with the kHigh_SkFilterQuality setting is 84 * expensive, so the result is saved in the global Scaled Image 85 * Cache. 86 * 87 * This function returns the memory usage of the Scaled Image Cache. 88 */ 89 static size_t GetResourceCacheTotalBytesUsed(); 90 91 /** 92 * These functions get/set the memory usage limit for the resource cache, used for temporary 93 * bitmaps and other resources. Entries are purged from the cache when the memory useage 94 * exceeds this limit. 95 */ 96 static size_t GetResourceCacheTotalByteLimit(); 97 static size_t SetResourceCacheTotalByteLimit(size_t newLimit); 98 99 /** 100 * For debugging purposes, this will attempt to purge the resource cache. It 101 * does not change the limit. 102 */ 103 static void PurgeResourceCache(); 104 105 /** 106 * When the cachable entry is very lage (e.g. a large scaled bitmap), adding it to the cache 107 * can cause most/all of the existing entries to be purged. To avoid the, the client can set 108 * a limit for a single allocation. If a cacheable entry would have been cached, but its size 109 * exceeds this limit, then we do not attempt to cache it at all. 110 * 111 * Zero is the default value, meaning we always attempt to cache entries. 112 */ 113 static size_t GetResourceCacheSingleAllocationByteLimit(); 114 static size_t SetResourceCacheSingleAllocationByteLimit(size_t newLimit); 115 116 /** 117 * Dumps memory usage of caches using the SkTraceMemoryDump interface. See SkTraceMemoryDump 118 * for usage of this method. 119 */ 120 static void DumpMemoryStatistics(SkTraceMemoryDump* dump); 121 122 /** 123 * Free as much globally cached memory as possible. This will purge all private caches in Skia, 124 * including font and image caches. 125 * 126 * If there are caches associated with GPU context, those will not be affected by this call. 127 */ 128 static void PurgeAllCaches(); 129 130 /** 131 * Applications with command line options may pass optional state, such 132 * as cache sizes, here, for instance: 133 * font-cache-limit=12345678 134 * 135 * The flags format is name=value[;name=value...] with no spaces. 136 * This format is subject to change. 137 */ 138 static void SetFlags(const char* flags); 139 140 /** 141 * Return the max number of bytes that should be used by the thread-local 142 * font cache. 143 * If the cache needs to allocate more, it will purge previous entries. 144 * This max can be changed by calling SetFontCacheLimit(). 145 * 146 * If this thread has never called SetTLSFontCacheLimit, or has called it 147 * with 0, then this thread is using the shared font cache. In that case, 148 * this function will always return 0, and the caller may want to call 149 * GetFontCacheLimit. 150 */ 151 static size_t GetTLSFontCacheLimit(); 152 153 /** 154 * Specify the max number of bytes that should be used by the thread-local 155 * font cache. If this value is 0, then this thread will use the shared 156 * global font cache. 157 */ 158 static void SetTLSFontCacheLimit(size_t bytes); 159 160 typedef std::unique_ptr<SkImageGenerator> 161 (*ImageGeneratorFromEncodedDataFactory)(sk_sp<SkData>); 162 163 /** 164 * To instantiate images from encoded data, first looks at this runtime function-ptr. If it 165 * exists, it is called to create an SkImageGenerator from SkData. If there is no function-ptr 166 * or there is, but it returns NULL, then skia will call its internal default implementation. 167 * 168 * Returns the previous factory (which could be NULL). 169 */ 170 static ImageGeneratorFromEncodedDataFactory 171 SetImageGeneratorFromEncodedDataFactory(ImageGeneratorFromEncodedDataFactory); 172 }; 173 174 class SkAutoGraphics { 175 public: 176 SkAutoGraphics() { 177 SkGraphics::Init(); 178 } 179 }; 180 181 #endif 182