1 2 /* 3 * Copyright 2006 The Android Open Source Project 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 9 10 #ifndef SkGraphics_DEFINED 11 #define SkGraphics_DEFINED 12 13 #include "SkTypes.h" 14 15 class SK_API SkGraphics { 16 public: 17 /** 18 * Call this at process initialization time if your environment does not 19 * permit static global initializers that execute code. Note that 20 * Init() is not thread-safe. 21 */ 22 static void Init(); 23 24 /** 25 * Call this to release any memory held privately, such as the font cache. 26 */ 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 SkPaint::kHigh_FilterLevel 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 #ifdef SK_SUPPORT_LEGACY_IMAGECACHE_NAME 117 static size_t GetImageCacheBytesUsed() { 118 return GetImageCacheTotalBytesUsed(); 119 } 120 static size_t GetImageCacheByteLimit() { 121 return GetImageCacheTotalByteLimit(); 122 } 123 static size_t SetImageCacheByteLimit(size_t newLimit) { 124 return SetImageCacheTotalByteLimit(newLimit); 125 } 126 static size_t GetImageCacheTotalBytesUsed() { 127 return GetResourceCacheTotalBytesUsed(); 128 } 129 static size_t GetImageCacheTotalByteLimit() { 130 return GetResourceCacheTotalByteLimit(); 131 } 132 static size_t SetImageCacheTotalByteLimit(size_t newLimit) { 133 return SetResourceCacheTotalByteLimit(newLimit); 134 } 135 static size_t GetImageCacheSingleAllocationByteLimit() { 136 return GetResourceCacheSingleAllocationByteLimit(); 137 } 138 static size_t SetImageCacheSingleAllocationByteLimit(size_t newLimit) { 139 return SetResourceCacheSingleAllocationByteLimit(newLimit); 140 } 141 #endif 142 143 /** 144 * Applications with command line options may pass optional state, such 145 * as cache sizes, here, for instance: 146 * font-cache-limit=12345678 147 * 148 * The flags format is name=value[;name=value...] with no spaces. 149 * This format is subject to change. 150 */ 151 static void SetFlags(const char* flags); 152 153 /** 154 * Return the max number of bytes that should be used by the thread-local 155 * font cache. 156 * If the cache needs to allocate more, it will purge previous entries. 157 * This max can be changed by calling SetFontCacheLimit(). 158 * 159 * If this thread has never called SetTLSFontCacheLimit, or has called it 160 * with 0, then this thread is using the shared font cache. In that case, 161 * this function will always return 0, and the caller may want to call 162 * GetFontCacheLimit. 163 */ 164 static size_t GetTLSFontCacheLimit(); 165 166 /** 167 * Specify the max number of bytes that should be used by the thread-local 168 * font cache. If this value is 0, then this thread will use the shared 169 * global font cache. 170 */ 171 static void SetTLSFontCacheLimit(size_t bytes); 172 173 private: 174 /** This is automatically called by SkGraphics::Init(), and must be 175 implemented by the host OS. This allows the host OS to register a callback 176 with the C++ runtime to call SkGraphics::FreeCaches() 177 */ 178 static void InstallNewHandler(); 179 }; 180 181 class SkAutoGraphics { 182 public: 183 SkAutoGraphics() { 184 SkGraphics::Init(); 185 } 186 ~SkAutoGraphics() { 187 SkGraphics::Term(); 188 } 189 }; 190 191 #endif 192
