Hyphenator.h revision daf6a6bdbf2ff1f66496d6200cb253e2f50759d5
1/* 2 * Copyright (C) 2015 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/** 18 * An implementation of Liang's hyphenation algorithm. 19 */ 20 21#include <memory> 22#include <unordered_map> 23 24#ifndef MINIKIN_HYPHENATOR_H 25#define MINIKIN_HYPHENATOR_H 26 27namespace android { 28 29class Trie { 30public: 31 std::vector<uint8_t> result; 32 std::unordered_map<uint16_t, Trie> succ; 33}; 34 35class Hyphenator { 36public: 37 // Note: this will also require a locale, for proper case folding behavior 38 static Hyphenator* load(const uint16_t* patternData, size_t size); 39 40 // Compute the hyphenation of a word, storing the hyphenation in result vector. Each 41 // entry in the vector is a "hyphen edit" to be applied at the corresponding code unit 42 // offset in the word. Currently 0 means no hyphen and 1 means insert hyphen and break, 43 // but this will be expanded to other edits for nonstandard hyphenation. 44 // Example: word is "hyphen", result is [0 0 1 0 0 0], corresponding to "hy-phen". 45 void hyphenate(std::vector<uint8_t>* result, const uint16_t* word, size_t len); 46 47private: 48 void addPattern(const uint16_t* pattern, size_t size); 49 50 void hyphenateSoft(std::vector<uint8_t>* result, const uint16_t* word, size_t len); 51 52 // TODO: these should become parameters, as they might vary by locale, screen size, and 53 // possibly explicit user control. 54 static const int MIN_PREFIX = 2; 55 static const int MIN_SUFFIX = 3; 56 57 Trie root; 58}; 59 60} // namespace android 61 62#endif // MINIKIN_HYPHENATOR_H