| /* |
| * |
| * (C) Copyright IBM Corp. 1998-2005 - All Rights Reserved |
| * |
| * Developed at DIT - Government of Bhutan |
| * |
| * Contact person: Pema Geyleg - <pema_geyleg@druknet.bt> |
| * |
| * This file is a modification of the ICU file KhmerReordering.h |
| * by Jens Herden and Javier Sola who have given all their possible rights to IBM and the Governement of Bhutan |
| * A first module for Dzongkha was developed by Karunakar under Panlocalisation funding. |
| * Assistance for this module has been received from Namgay Thinley, Christopher Fynn and Javier Sola |
| * |
| */ |
| |
| #ifndef __TIBETANREORDERING_H |
| #define __TIBETANORDERING_H |
| |
| /** |
| * \file |
| * \internal |
| */ |
| |
| // #include "LETypes.h" |
| // #include "OpenTypeTables.h" |
| |
| U_NAMESPACE_BEGIN |
| |
| class LEGlyphStorage; |
| |
| // Vocabulary |
| // Base -> A consonant in its full (not subscript) form. It is the |
| // center of the syllable, it can be souranded by subjoined consonants, vowels, |
| // signs... but there is only one base in a stack, it has to be coded as |
| // the first character of the syllable.Included here are also groups of base + subjoined |
| // which are represented by one single code point in unicode (e.g. 0F43) Also other characters that might take |
| // subjoined consonants or other combining characters. |
| // Subjoined -> Subjoined consonants and groups of subjoined consonants which have a single code-point |
| // to repersent the group (even if each subjoined consonant is represented independently |
| // by anothe code-point |
| // Tsa Phru --> Tsa Phru character, Bhutanese people will always place it right after the base, but sometimes, due to |
| // "normalization" |
| // is placed after all the subjoined consonants, and it is also permitted there. |
| // A Chung Vowel lengthening mark --> . 0F71 It is placed after the base and any subjoined consonants but before any vowels |
| // Precomposed Sanskrit vowels --> The are combinations of subjoined consonants + vowels that have been assigned |
| // a given code-point (in spite of each single part of them having also a code-point |
| // They are avoided, and users are encouraged to use the combination of code-points that |
| // represents the same sound instead of using this combined characters. This is included here |
| // for compatibility with possible texts that use them (they are not in the Dzongkha keyboard). |
| // Halanta -> The Halanta or Virama character 0F84 indicates that a consonant should not use its inheernt vowel, |
| // in spite of not having other vowels present. It is usually placed immediatly after a base consonant, |
| // but in some special cases it can also be placed after a subjoined consonant, so this is also |
| // permitted in this algorithm. (Halanta is always displayed in Tibetan not used as a connecting char) |
| // |
| // Subjoined vowels -> Dependent vowels (matras) placed below the base and below all subjoined consonants. There |
| // might be as much as three subjoined vowels in a given stack (only one in general text, but up |
| // to three for abreviations, they have to be permitted). |
| // Superscript vowels -> There are three superscript vowels, and they can be repeated or combined (up to three |
| // times. They can combine with subjoined vowels, and are always coded after these. |
| // Anusvara --> Nasalisation sign. Traditioinally placed in absence of vowels, but also after vowels. In some |
| // special cases it can be placed before a vowel, so this is also permitted |
| // Candrabindu -> Forms of the Anusvara with different glyphs (and different in identity) which can be placed |
| // without vowel or after the vowel, but never before. Cannot combine with Anusvara. |
| // Stress marks -> Marks placed above or below a syllable, affecting the whole syllable. They are combining |
| // marks, so they have to be attached to a specific stack. The are using to emphasise a syllable. |
| // |
| // Digits -> Digits are not considered as non-combining characters because there are a few characters which |
| // combine with them, so they have to be considered independently. |
| // Digit combining marks -> dependent marks that combine with digits. |
| // |
| // TODO |
| // There are a number of characters in the CJK block that are used in Tibetan script, two of these are symbols |
| // are used as bases for combining glyphs, and have not been encoded in Tibetan. As these characters are outside |
| // of the tibetan block, they have not been treated in this program. |
| |
| |
| struct TibetanClassTable // This list must include all types of components that can be used inside a syllable |
| { |
| enum CharClassValues // order is important here! This order must be the same that is found in each horizontal |
| // line in the statetable for Tibetan (file TibetanReordering.cpp). It assigns one number |
| // to each type of character that has to be considered when analysing the order in which |
| // characters can be placed |
| { |
| CC_RESERVED = 0, //Non Combining Characters |
| CC_BASE = 1, // Base Consonants, Base Consonants with Subjoined attached in code point, Sanskrit base marks |
| CC_SUBJOINED = 2, // Subjoined Consonats, combination of more than Subjoined Consonants in the code point |
| CC_TSA_PHRU = 3, // Tsa-Phru character 0F39 |
| CC_A_CHUNG = 4, // Vowel Lenthening a-chung mark 0F71 |
| CC_COMP_SANSKRIT = 5, // Precomposed Sanskrit vowels including Subjoined characters and vowels |
| CC_HALANTA = 6, // Halanta Character 0F84 |
| CC_BELOW_VOWEL = 7, // Subjoined vowels |
| CC_ABOVE_VOWEL = 8, // Superscript vowels |
| CC_ANUSVARA = 9, // Tibetan sign Rjes Su Nga Ro 0F7E |
| CC_CANDRABINDU = 10, // Tibetan sign Sna Ldan and Nyi Zla Naa Da 0F82, 0F83 |
| CC_VISARGA = 11, // Tibetan sign Rnam Bcad (0F7F) |
| CC_ABOVE_S_MARK = 12, // Stress Marks placed above the text |
| CC_BELOW_S_MARK = 13, // Stress Marks placed below the text |
| CC_DIGIT = 14, // Dzongkha Digits |
| CC_PRE_DIGIT_MARK = 15, // Mark placed before the digit |
| CC_POST_BELOW_DIGIT_M = 16, // Mark placed below or after the digit |
| CC_COUNT = 17 // This is the number of character classes |
| }; |
| |
| enum CharClassFlags |
| { |
| CF_CLASS_MASK = 0x0000FFFF, |
| |
| CF_DOTTED_CIRCLE = 0x04000000, // add a dotted circle if a character with this flag is the first in a syllable |
| CF_DIGIT = 0x01000000, // flag to speed up comparaisson |
| CF_PREDIGIT = 0x02000000, // flag to detect pre-digit marks for reordering |
| |
| // position flags |
| CF_POS_BEFORE = 0x00080000, |
| CF_POS_BELOW = 0x00040000, |
| CF_POS_ABOVE = 0x00020000, |
| CF_POS_AFTER = 0x00010000, |
| CF_POS_MASK = 0x000f0000 |
| }; |
| |
| typedef le_uint32 CharClass; |
| |
| typedef le_int32 ScriptFlags; |
| |
| LEUnicode firstChar; // for Tibetan this will become xOF00 |
| LEUnicode lastChar; // and this x0FFF |
| const CharClass *classTable; |
| |
| CharClass getCharClass(LEUnicode ch) const; |
| |
| static const TibetanClassTable *getTibetanClassTable(); |
| }; |
| |
| |
| class TibetanReordering /* not : public UObject because all methods are static */ { |
| public: |
| static le_int32 reorder(const LEUnicode *theChars, le_int32 charCount, le_int32 scriptCode, |
| LEUnicode *outChars, LEGlyphStorage &glyphStorage); |
| |
| static const FeatureMap *getFeatureMap(le_int32 &count); |
| |
| private: |
| // do not instantiate |
| TibetanReordering(); |
| |
| static le_int32 findSyllable(const TibetanClassTable *classTable, const LEUnicode *chars, le_int32 prev, le_int32 charCount); |
| |
| }; |
| |
| |
| U_NAMESPACE_END |
| #endif |
