Home | History | Annotate | Download | only in minikin
      1 /*
      2  * Copyright (C) 2014 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_GRAPHEME_BREAK_H
     18 #define MINIKIN_GRAPHEME_BREAK_H
     19 
     20 namespace minikin {
     21 
     22 class GraphemeBreak {
     23 public:
     24     // These values must be kept in sync with CURSOR_AFTER etc in Paint.java
     25     enum MoveOpt {
     26         AFTER = 0,
     27         AT_OR_AFTER = 1,
     28         BEFORE = 2,
     29         AT_OR_BEFORE = 3,
     30         AT = 4
     31     };
     32 
     33     // Determine whether the given offset is a grapheme break.
     34     // This implementation generally follows Unicode's UTR #29 extended
     35     // grapheme break, with various tweaks.
     36     static bool isGraphemeBreak(const float* advances, const uint16_t* buf, size_t start,
     37             size_t count, size_t offset);
     38 
     39     // Matches Android's Java API. Note, return (size_t)-1 for AT to
     40     // signal non-break because unsigned return type.
     41     static size_t getTextRunCursor(const float* advances, const uint16_t* buf, size_t start,
     42             size_t count, size_t offset, MoveOpt opt);
     43 };
     44 
     45 }  // namespace minikin
     46 
     47 #endif  // MINIKIN_GRAPHEME_BREAK_H
     48