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Diffstat (limited to 'bidi.h')
| -rw-r--r-- | bidi.h | 122 |
1 files changed, 122 insertions, 0 deletions
@@ -0,0 +1,122 @@ +// Copyright (C) 2003 Mooffie <mooffie@typo.co.il> +// +// This program is free software; you can redistribute it and/or modify +// it under the terms of the GNU General Public License as published by +// the Free Software Foundation; either version 2 of the License, or +// (at your option) any later version. +// +// This program is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License +// along with this program; if not, write to the Free Software +// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA. + +#ifndef BDE_BIDI_H +#define BDE_BIDI_H + +#include "types.h" + +// The purpose of the BiDi class (and the public typdefs) is to make the +// interface of the actual BiDi engine (FriBiDi) hidden from the user. This +// BiDi class could be implemented using other engines, e.g. IBM's ICU. +// +// Ideally, The BiDi class would be an abstract class from which we derive +// class FriBiDi, class ICUBiDi etc. The configre script could then tell us +// which class to use based on what engine the system has. +// +// Note that we use very little of FriBiDi. We implement reordering ourselves +// (see the comments at EditBox::reorder()). + +typedef FriBidiCharType ctype_t; +typedef FriBidiLevel level_t; +enum direction_t { dirLTR, dirRTL, dirN }; +enum diralgo_t { algoUnicode, algoContextStrong, algoContextRTL, algoForceLTR, algoForceRTL }; + +#include "univalues.h" + +class BiDi { + +public: + + static bool mirror_char(unichar *ch) { + return fribidi_get_mirror_char(*ch, ch); + } + + static bool is_space(unichar ch) { + return FRIBIDI_IS_SPACE(fribidi_get_type(ch)); + } + + static bool is_alnum(unichar ch) { + ctype_t ctype = fribidi_get_type(ch); + return FRIBIDI_IS_LETTER(ctype) || FRIBIDI_IS_NUMBER(ctype); + } + + static bool is_nsm(unichar ch) { + return fribidi_get_type(ch) == FRIBIDI_TYPE_NSM; + } + + // is_wordch() returns what constitutes a word. + static bool is_wordch(unichar ch) { + return is_alnum(ch) || is_nsm(ch); + } + + static bool is_rtl(unichar ch) { + return FRIBIDI_IS_RTL(fribidi_get_type(ch)); + } + + static bool is_explicit_mark(unichar ch) + { + return ch == UNI_LRM || + ch == UNI_RLM || + ch == UNI_LRE || + ch == UNI_RLE || + ch == UNI_PDF || + ch == UNI_LRO || + ch == UNI_RLO; + } + + static bool is_transparent_formatting_code(unichar ch) + { + return is_explicit_mark(ch) || + ch == UNI_ZWNJ || + ch == UNI_ZWJ; + } + + static bool is_hebrew_nsm(unichar ch) + { + return (ch >= UNI_HEB_ETNAHTA && ch <= UNI_HEB_UPPER_DOT + || ch == UNI_NS_UNDERSCORE) + && (ch != UNI_HEB_MAQAF && + ch != UNI_HEB_PASEQ && + ch != UNI_HEB_SOF_PASUQ); + } + + static bool is_arabic_nsm(unichar ch) + { + return (ch >= UNI_ARA_FATHATAN && ch <= UNI_ARA_SUKUN + || ch == UNI_ARA_SUPERSCIPT_ALEF); + } + + static bool is_cantillation_nsm(unichar ch) + { + return (ch >= UNI_HEB_ETNAHTA && ch <= UNI_HEB_MASORA_CIRCLE); + } + + static void get_embedding_levels(unichar *str, idx_t len, + direction_t dir, + level_t *levels, + int line_breaks_count = 0, + idx_t *line_breaks = NULL, + bool disable_bidi = false); + + static direction_t determine_base_dir(unichar *str, idx_t len, + diralgo_t dir_algo); + + static void simple_log2vis(unistring &str, direction_t dir, unistring &dest); +}; + +#endif + |