1 // Copyright 2019 Google LLC. 2 #ifndef ParagraphCache_DEFINED 3 #define ParagraphCache_DEFINED 4 5 #include "include/private/base/SkMutex.h" 6 #include "src/core/SkLRUCache.h" 7 #include <functional> // std::function 8 9 #define PARAGRAPH_CACHE_STATS 10 11 namespace skia { 12 namespace textlayout { 13 14 class ParagraphImpl; 15 class ParagraphCacheKey; 16 class ParagraphCacheValue; 17 18 class ParagraphCache { 19 public: 20 ParagraphCache(); 21 ~ParagraphCache(); 22 23 void abandon(); 24 void reset(); 25 bool updateParagraph(ParagraphImpl* paragraph); 26 bool findParagraph(ParagraphImpl* paragraph); 27 #ifdef ENABLE_TEXT_ENHANCE 28 void SetStoredLayout(ParagraphImpl& paragraph); 29 bool GetStoredLayout(ParagraphImpl& paragraph); 30 #endif 31 32 // For testing setChecker(std::function<void (ParagraphImpl * impl,const char *,bool)> checker)33 void setChecker(std::function<void(ParagraphImpl* impl, const char*, bool)> checker) { 34 fChecker = std::move(checker); 35 } 36 void printStatistics(); turnOn(bool value)37 void turnOn(bool value) { fCacheIsOn = value; } count()38 int count() { return fLRUCacheMap.count(); } 39 40 bool isPossiblyTextEditing(ParagraphImpl* paragraph); 41 42 private: 43 44 struct Entry; 45 void updateFrom(const ParagraphImpl* paragraph, Entry* entry); 46 void updateTo(ParagraphImpl* paragraph, const Entry* entry); 47 48 #ifdef ENABLE_TEXT_ENHANCE 49 bool useCachedLayout(const ParagraphImpl& paragraph, const ParagraphCacheValue* value); 50 void SetStoredLayoutImpl(ParagraphImpl& paragraph, ParagraphCacheValue* value); 51 ParagraphCacheValue* cacheLayout(ParagraphImpl* paragraph); 52 bool canBeCached(ParagraphImpl* paragraph) const; 53 #endif 54 55 mutable SkMutex fParagraphMutex; 56 std::function<void(ParagraphImpl* impl, const char*, bool)> fChecker; 57 58 static const int kMaxEntries = 128; 59 60 struct KeyHash { 61 uint32_t operator()(const ParagraphCacheKey& key) const; 62 }; 63 64 SkLRUCache<ParagraphCacheKey, std::unique_ptr<Entry>, KeyHash> fLRUCacheMap; 65 bool fCacheIsOn; 66 ParagraphCacheValue* fLastCachedValue; 67 68 #ifdef PARAGRAPH_CACHE_STATS 69 int fTotalRequests; 70 int fCacheMisses; 71 int fHashMisses; // cache hit but hash table missed 72 #endif 73 }; 74 75 } // namespace textlayout 76 } // namespace skia 77 78 #endif // ParagraphCache_DEFINED 79