1 /* 2 * Copyright (C) 2013 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef MINIKIN_FONT_COLLECTION_H 18 #define MINIKIN_FONT_COLLECTION_H 19 20 #include <memory> 21 #include <unordered_set> 22 #include <vector> 23 24 #include "minikin/FontFamily.h" 25 #include "minikin/MinikinFont.h" 26 27 namespace minikin { 28 29 // The maximum number of font families. 30 constexpr uint32_t MAX_FAMILY_COUNT = 254; 31 32 class FontCollection { 33 public: 34 explicit FontCollection(const std::vector<std::shared_ptr<FontFamily>>& typefaces); 35 explicit FontCollection(std::shared_ptr<FontFamily>&& typeface); 36 37 struct Run { 38 FakedFont fakedFont; 39 int start; 40 int end; 41 }; 42 43 void itemize(const uint16_t* string, size_t string_length, const MinikinPaint& paint, 44 std::vector<Run>* result) const; 45 46 // Returns true if there is a glyph for the code point and variation selector pair. 47 // Returns false if no fonts have a glyph for the code point and variation 48 // selector pair, or invalid variation selector is passed. 49 bool hasVariationSelector(uint32_t baseCodepoint, uint32_t variationSelector) const; 50 51 // Get base font with fakery information (fake bold could affect metrics) 52 FakedFont baseFontFaked(FontStyle style); 53 54 // Creates new FontCollection based on this collection while applying font variations. Returns 55 // nullptr if none of variations apply to this collection. 56 std::shared_ptr<FontCollection> createCollectionWithVariation( 57 const std::vector<FontVariation>& variations); 58 59 const std::unordered_set<AxisTag>& getSupportedTags() const { return mSupportedAxes; } 60 61 uint32_t getId() const; 62 63 private: 64 static const int kLogCharsPerPage = 8; 65 static const int kPageMask = (1 << kLogCharsPerPage) - 1; 66 67 // mFamilyVec holds the indices of the mFamilies and mRanges holds the range of indices of 68 // mFamilyVec. The maximum number of pages is 0x10FF (U+10FFFF >> 8). The maximum number of 69 // the fonts is 0xFF. Thus, technically the maximum length of mFamilyVec is 0x10EE01 70 // (0x10FF * 0xFF). However, in practice, 16-bit integers are enough since most fonts supports 71 // only limited range of code points. 72 struct Range { 73 uint16_t start; 74 uint16_t end; 75 }; 76 77 // Initialize the FontCollection. 78 void init(const std::vector<std::shared_ptr<FontFamily>>& typefaces); 79 80 const std::shared_ptr<FontFamily>& getFamilyForChar(uint32_t ch, uint32_t vs, 81 uint32_t localeListId, 82 FontFamily::Variant variant) const; 83 84 uint32_t calcFamilyScore(uint32_t ch, uint32_t vs, FontFamily::Variant variant, 85 uint32_t localeListId, 86 const std::shared_ptr<FontFamily>& fontFamily) const; 87 88 uint32_t calcCoverageScore(uint32_t ch, uint32_t vs, uint32_t localeListId, 89 const std::shared_ptr<FontFamily>& fontFamily) const; 90 91 static uint32_t calcLocaleMatchingScore(uint32_t userLocaleListId, 92 const FontFamily& fontFamily); 93 94 static uint32_t calcVariantMatchingScore(FontFamily::Variant variant, 95 const FontFamily& fontFamily); 96 97 // unique id for this font collection (suitable for cache key) 98 uint32_t mId; 99 100 // Highest UTF-32 code point that can be mapped 101 uint32_t mMaxChar; 102 103 // This vector has pointers to the all font family instances in this collection. 104 // This vector can't be empty. 105 std::vector<std::shared_ptr<FontFamily>> mFamilies; 106 107 // Following two vectors are pre-calculated tables for resolving coverage faster. 108 // For example, to iterate over all fonts which support Unicode code point U+XXYYZZ, 109 // iterate font families index from mFamilyVec[mRanges[0xXXYY].start] to 110 // mFamilyVec[mRange[0xXXYY].end] instead of whole mFamilies. 111 // This vector contains indices into mFamilies. 112 // This vector can't be empty. 113 std::vector<Range> mRanges; 114 std::vector<uint8_t> mFamilyVec; 115 116 // This vector has pointers to the font family instances which have cmap 14 subtables. 117 std::vector<std::shared_ptr<FontFamily>> mVSFamilyVec; 118 119 // Set of supported axes in this collection. 120 std::unordered_set<AxisTag> mSupportedAxes; 121 }; 122 123 } // namespace minikin 124 125 #endif // MINIKIN_FONT_COLLECTION_H 126
