1 2 /* 3 * Copyright 2011 Google Inc. 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 SkBitSet_DEFINED 11 #define SkBitSet_DEFINED 12 13 #include "SkTypes.h" 14 #include "SkTDArray.h" 15 16 class SkBitSet { 17 public: 18 /** NumberOfBits must be greater than zero. 19 */ 20 explicit SkBitSet(int numberOfBits); 21 explicit SkBitSet(const SkBitSet& source); 22 23 SkBitSet& operator=(const SkBitSet& rhs); 24 bool operator==(const SkBitSet& rhs); 25 bool operator!=(const SkBitSet& rhs); 26 27 /** Clear all data. 28 */ 29 void clearAll(); 30 31 /** Set the value of the index-th bit. 32 */ 33 void setBit(int index, bool value); 34 35 /** Test if bit index is set. 36 */ 37 bool isBitSet(int index) const; 38 39 /** Or bits from source. false is returned if this doesn't have the same 40 * bit count as source. 41 */ 42 bool orBits(const SkBitSet& source); 43 44 /** Export indices of set bits to T array. 45 */ 46 template<typename T> 47 void exportTo(SkTDArray<T>* array) const { 48 SkASSERT(array); 49 uint32_t* data = reinterpret_cast<uint32_t*>(fBitData.get()); 50 for (unsigned int i = 0; i < fDwordCount; ++i) { 51 uint32_t value = data[i]; 52 if (value) { // There are set bits 53 unsigned int index = i * 32; 54 for (unsigned int j = 0; j < 32; ++j) { 55 if (0x1 & (value >> j)) { 56 array->push(index + j); 57 } 58 } 59 } 60 } 61 } 62 63 private: 64 SkAutoFree fBitData; 65 // Dword (32-bit) count of the bitset. 66 size_t fDwordCount; 67 size_t fBitCount; 68 69 uint32_t* internalGet(int index) const { 70 SkASSERT((size_t)index < fBitCount); 71 size_t internalIndex = index / 32; 72 SkASSERT(internalIndex < fDwordCount); 73 return reinterpret_cast<uint32_t*>(fBitData.get()) + internalIndex; 74 } 75 }; 76 77 78 #endif 79
