/* Pango * tibetan-fc.c: Shaper for Tibetan script * * Copyright (C) 2005 DIT, Government of Bhutan * Contact person : Pema Geyleg * * Based on code from khmer shapers developed by Jens Herden * and Javier Sola * * Based on code from other shapers * Copyright (C) 1999-2004 Red Hat Software * Author: Owen Taylor * Partially based on Indic shaper * Copyright (C) 2001, 2002 IBM Corporation * Author: Eric Mader * * The first module for Tibetan shaper was developed by Mr. Karunakar under * PanLocalization project. * Mr. Chris Fynn, Mr.Javier Sola, Mr. Namgay Thinley were involved * while developing this shaper. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library 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 * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. * * The license on the original Indic shaper code is as follows: * * Permission is hereby granted, free of charge, to any person * obtaining a copy of this software and associated documentation * files (the "Software"), to deal in the Software without * restriction, including without limitation the rights to use, copy, * modify, merge, publish, distribute, and/or sell copies of the * Software, and to permit persons to whom the Software is furnished * to do so, provided that the above copyright notice(s) and this * permission notice appear in all copies of the Software and that * both the above copyright notice(s) and this permission notice * appear in supporting documentation. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT OF THIRD PARTY RIGHTS. IN NO EVENT SHALL THE * COPYRIGHT HOLDER OR HOLDERS INCLUDED IN THIS NOTICE BE LIABLE FOR * ANY CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY * DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, * WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE * OF THIS SOFTWARE. * * Except as contained in this notice, the name of a copyright holder * shall not be used in advertising or otherwise to promote the sale, * use or other dealings in this Software without prior written * authorization of the copyright holder. */ #include #include #include "pango-engine.h" #include "pango-ot.h" #include "pango-utils.h" #include "pangofc-font.h" #define SCRIPT_ENGINE_NAME "TibetanScriptEngineFc" #define RENDER_TYPE PANGO_RENDER_TYPE_FC typedef PangoEngineShape TibetanEngineFc; typedef PangoEngineShapeClass TibetanEngineFcClass ; static PangoEngineScriptInfo tibetan_scripts[] = { { PANGO_SCRIPT_TIBETAN, "*" } }; static PangoEngineInfo script_engines[] = { { SCRIPT_ENGINE_NAME, PANGO_ENGINE_TYPE_SHAPE, RENDER_TYPE, tibetan_scripts, G_N_ELEMENTS (tibetan_scripts) } }; /* * 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. */ enum TibetanCharClassValues { 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 TibetanCharClassFlags { 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 }; /* Characters that get refrered to by name */ enum TibetanChar { C_DOTTED_CIRCLE = 0x25CC, C_PRE_NUMBER_MARK = 0x0F3F }; enum { /* simple classes, they are used in the statetable (in this file) to control the length of a syllable * they are also used to know where a character should be placed (location in reference to the base character) * and also to know if a character, when independtly displayed, should be displayed with a dotted-circle to * indicate error in syllable construction */ _xx = CC_RESERVED, _ba = CC_BASE, _sj = CC_SUBJOINED | CF_DOTTED_CIRCLE | CF_POS_BELOW, _tp = CC_TSA_PHRU | CF_DOTTED_CIRCLE | CF_POS_ABOVE, _ac = CC_A_CHUNG | CF_DOTTED_CIRCLE | CF_POS_BELOW, _cs = CC_COMP_SANSKRIT | CF_DOTTED_CIRCLE | CF_POS_BELOW, _ha = CC_HALANTA | CF_DOTTED_CIRCLE | CF_POS_BELOW, _bv = CC_BELOW_VOWEL | CF_DOTTED_CIRCLE | CF_POS_BELOW, _av = CC_ABOVE_VOWEL | CF_DOTTED_CIRCLE | CF_POS_ABOVE, _an = CC_ANUSVARA | CF_DOTTED_CIRCLE | CF_POS_ABOVE, _cb = CC_CANDRABINDU | CF_DOTTED_CIRCLE | CF_POS_ABOVE, _vs = CC_VISARGA | CF_DOTTED_CIRCLE| CF_POS_AFTER, _as = CC_ABOVE_S_MARK | CF_DOTTED_CIRCLE | CF_POS_ABOVE, _bs = CC_BELOW_S_MARK | CF_DOTTED_CIRCLE | CF_POS_BELOW, _di = CC_DIGIT | CF_DIGIT, _pd = CC_PRE_DIGIT_MARK | CF_DOTTED_CIRCLE | CF_PREDIGIT | CF_POS_BEFORE , _bd = CC_POST_BELOW_DIGIT_M | CF_DOTTED_CIRCLE | CF_POS_AFTER }; /* Character class: a character class value * ORed with character class flags. */ typedef glong TibetanCharClass; /*_xx Non Combining characters*/ /*_ba Base Consonants*/ /*_sj Subjoined consonants*/ /*_tp Tsa - phru*/ /*_ac A-chung, Vowel Lengthening mark*/ /*_cs Precomposed Sanskrit vowel + subjoined consonants*/ /*_ha Halanta/Virama*/ /*_bv Below vowel*/ /*_av above vowel*/ /*_an Anusvara*/ /*_cb Candrabindu*/ /*_vs Visaraga/Post mark*/ /*_as Upper Stress marks*/ /*_bs Lower Stress marks*/ /*_di Digit*/ /*_pd Number pre combining, Needs reordering*/ /*_bd Other number combining marks*/ static const TibetanCharClass tibetanCharClasses[] = { /* 0 1 2 3 4 5 6 7 8 9 a b c d e f*/ _xx, _ba, _xx, _xx, _ba, _ba, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, /* 0F00 - 0F0F 0*/ _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _bd, _bd, _xx, _xx, _xx, _xx, _xx, _xx, /* 0F10 - 0F1F 1*/ _di, _di, _di, _di, _di, _di, _di, _di, _di, _di, _xx, _xx, _xx, _xx, _xx, _xx, /* 0F20 - 0F2F 2*/ _xx, _xx, _xx, _xx, _xx, _bs, _xx, _bs, _xx, _tp, _xx, _xx, _xx, _xx, _bd, _pd, /* 0F30 - 0F3F 3*/ _ba, _ba, _ba, _ba, _ba, _ba, _ba, _ba, _xx, _ba, _ba, _ba, _ba, _ba, _ba, _ba, /* 0F40 - 0F4F 4*/ _ba, _ba, _ba, _ba, _ba, _ba, _ba, _ba, _ba, _ba, _ba, _ba, _ba, _ba, _ba, _ba, /* 0F50 - 0F5F 5*/ _ba, _ba, _ba, _ba, _ba, _ba, _ba, _ba, _ba, _ba, _ba, _xx, _xx, _xx, _xx, _xx, /* 0F60 - 0F6F 6*/ _xx, _ac, _av, _cs, _bv, _bv, _cs, _cs, _cs, _cs, _av, _av, _av, _av, _an, _vs, /* 0F70 - 0F7F 7*/ _av, _cs, _cb, _cb, _ha, _xx, _as, _as, _ba, _ba, _ba, _ba, _xx, _xx, _xx, _xx, /* 0F80 - 0F8F 8*/ _sj, _sj, _sj, _sj, _sj, _sj, _sj, _sj, _xx, _sj, _sj, _sj, _sj, _sj, _sj, _sj, /* 0F90 - 0F9F 9*/ _sj, _sj, _sj, _sj, _sj, _sj, _sj, _sj, _sj, _sj, _sj, _sj, _sj, _sj, _sj, _sj, /* 0FA0 - 0FAF a*/ _sj, _sj, _sj, _sj, _sj, _sj, _sj, _sj, _sj, _sj, _sj, _sj, _sj, _xx, _sj, _sj, /* 0FB0 - 0FBF b*/ _xx, _xx, _xx, _xx, _xx, _xx, _bs, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, /* 0FC0 - 0FCF c*/ _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, /* 0FD0 - 0FDF d*/ _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, /* 0FE0 - 0FEF e*/ _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, /* 0FF0 - 0FFF f*/ }; /* this define must reflect the range of tibetanCharClasses */ /*First Tibetan Character*/ #define firstChar 0x0F00 /*Last Tibetan Character*/ #define lastChar 0x0FFF /* The stateTable is used to calculate the end (the length) of a well * formed Tibetan Stack * * Each horizontal line is ordered exactly the same way as the values in TibetanClassTable * CharClassValues.This coincidence of values allows the follow up of the table. * * Each line corresponds to a state, which does not necessarily need to be a type * of component... for example, state 2 is a base, with is always a first character * in the Stack but the state could be produced a consonant of any type when * it is the first character that is analysed (in ground state). */ static const gint8 tibetanStateTable[][CC_COUNT] = { /*Dzongkha state table*/ /*xx ba sj tp ac cs ha bv av an cb vs as bs di pd bd*/ { 1, 2, 4, 3, 8, 7, 9, 10, 14, 13, 17, 18, 19, 19, 20, 21, 21,}, /* 0 - ground state*/ {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,}, /* 1 - exit state (or sign to the right of the syllable)*/ {-1, -1, 4, 3, 8, 7, 9, 10, 14, 13, 17, 18, 19, 19, -1, -1, -1,}, /* 2 - Base consonant*/ {-1, -1, 5, -1, 8, 7, -1, 10, 14, 13, 17, 18, 19, 19, -1, -1, -1,}, /* 3 - Tsa phru after base*/ {-1, -1, 4, 6, 8, 7, 9, 10, 14, 13, 17, 18, 19, 19, -1, -1, -1,}, /* 4 - Subjoined consonant after base*/ {-1, -1, 5, -1, 8, 7, -1, 10, 14, 13, 17, 18, 19, 19, -1, -1, -1,}, /* 5 - Subjoined consonant after tsa phru*/ {-1, -1, -1, -1, 8, 7, -1, 10, 14, 13, 17, 18, 19, 19, -1, -1, -1,}, /* 6 - Tsa phru after subjoined consonant*/ {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 19, 19, -1, -1, -1,}, /* 7 - Pre Composed Sanskrit*/ {-1, -1, -1, -1, -1, -1, -1, 10, 14, 13, 17, 18, 19, 19, -1, -1, -1,}, /* 8 - A-chung*/ {-1, -1, -1, -1, -1, -1, -1, -1, 14, 13, 17, -1, 19, 19, -1, -1, -1,}, /* 9 - Halanta*/ {-1, -1, -1, -1, -1, -1, -1, 11, 14, 13, 17, 18, 19, 19, -1, -1, -1,}, /* 10 - below vowel 1*/ {-1, -1, -1, -1, -1, -1, -1, 12, 14, 13, 17, 18, 19, 19, -1, -1, -1,}, /* 11 - below vowel 2*/ {-1, -1, -1, -1, -1, -1, -1, -1, 14, 13, 17, 18, 19, 19, -1, -1, -1,}, /* 12 - below vowel 3*/ {-1, -1, -1, -1, -1, -1, -1, -1, 14, 17, 17, 18, 19, 19, -1, -1, -1,}, /* 13 - Anusvara before vowel*/ {-1, -1, -1, -1, -1, -1, -1, -1, 15, 17, 17, 18, 19, 19, -1, -1, -1,}, /* 14 - above vowel 1*/ {-1, -1, -1, -1, -1, -1, -1, -1, 16, 17, 17, 18, 19, 19, -1, -1, -1,}, /* 15 - above vowel 2*/ {-1, -1, -1, -1, -1, -1, -1, -1, -1, 17, 17, 18, 19, 19, -1, -1, -1,}, /* 16 - above vowel 3*/ {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 18, 19, 19, -1, -1, -1,}, /* 17 - Anusvara or Candrabindu after vowel*/ {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 19, 19, -1, -1, -1,}, /* 18 - Visarga*/ {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,}, /* 19 - strss mark*/ {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 21, 21,}, /* 20 - digit*/ {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,}, /* 21 - digit mark*/ }; enum property_flags { abvf = 0x0001, pref = 0x0002, pstf = 0x0004, blwf = 0x0008, pres = 0x0010, blws = 0x0020, abvs = 0x0040, psts = 0x0080, clig = 0x0100, dist = 0x0200, blwm = 0x0400, abvm = 0x0800, mkmk = 0x1000 }; enum properties { blwf_p = /*(blwf | blws | clig | dist | blwm | mkmk)*/ (abvf | pref | pstf | pres | abvs | psts | abvm), pstf_p = /*(blwf | blws | pref | pres | pstf | psts | clig | dist | blwm)*/ (abvf | abvs | abvm | mkmk), abvf_p = /*(abvf | abvs | clig | dist | abvm | mkmk)*/ (pref | pstf | blwf | pres | blws | psts | blwm), pref_p = /*(pref | pres | clig | dist)*/ (abvf | pstf | blwf | blws | abvs | psts | blwm | abvm | mkmk), default_p = /*(pres | blws | clig | dist | abvm | blwm | mkmk)*/ (pref | blwf |abvf | pstf | abvs | psts) }; /* Below we define how a character in the input string is either in the tibetanCharClasses table * (in which case we get its type back), or an unknown object in which case we get _xx (CC_RESERVED) back */ static TibetanCharClass get_char_class (gunichar ch) { if (ch < firstChar || ch > lastChar) return CC_RESERVED; return tibetanCharClasses[ch - firstChar]; } /* Given an input string of characters and a location in which to start looking * calculate, using the state table, which one is the last character of the syllable * that starts in the starting position. */ static glong find_syllable (const gunichar *chars, glong start, glong char_count) { glong cursor = start; gint8 state = 0; TibetanCharClass charClass; while (cursor < char_count) { charClass = get_char_class (chars[cursor]) & CF_CLASS_MASK; state = tibetanStateTable[state][charClass]; if (state < 0) break; cursor += 1; } return cursor; } static void maybe_add_GSUB_feature (PangoOTRuleset *ruleset, PangoOTInfo *info, guint script_index, PangoOTTag tag, gulong property_bit) { guint feature_index; /* 0xffff == default language system */ if (pango_ot_info_find_feature (info, PANGO_OT_TABLE_GSUB, tag, script_index, 0xffff, &feature_index)) pango_ot_ruleset_add_feature (ruleset, PANGO_OT_TABLE_GSUB, feature_index, property_bit); } static void maybe_add_GPOS_feature (PangoOTRuleset *ruleset, PangoOTInfo *info, guint script_index, PangoOTTag tag, gulong property_bit) { guint feature_index; /* 0xffff == default language system */ if (pango_ot_info_find_feature (info, PANGO_OT_TABLE_GPOS, tag, script_index, 0xffff, &feature_index)) pango_ot_ruleset_add_feature (ruleset, PANGO_OT_TABLE_GPOS, feature_index, property_bit); } /* Rules found in the Open type font features */ static PangoOTRuleset * get_ruleset (FT_Face face) { PangoOTRuleset *ruleset; static GQuark ruleset_quark = 0; PangoOTInfo *info = pango_ot_info_get (face); if (!ruleset_quark) ruleset_quark = g_quark_from_string ("pango-tibetan-ruleset"); if (!info) return NULL; ruleset = g_object_get_qdata (G_OBJECT (info), ruleset_quark); if (!ruleset) { PangoOTTag tibetan_tag = FT_MAKE_TAG ('t', 'i', 'b', 't'); guint script_index; ruleset = pango_ot_ruleset_new (info); if (pango_ot_info_find_script (info, PANGO_OT_TABLE_GSUB, tibetan_tag, &script_index)) { maybe_add_GSUB_feature (ruleset, info, script_index, FT_MAKE_TAG ('p','r','e','f'), pref); maybe_add_GSUB_feature (ruleset, info, script_index, FT_MAKE_TAG ('b','l','w','f'), blwf); maybe_add_GSUB_feature (ruleset, info, script_index, FT_MAKE_TAG ('a','b','v','f'), abvf); maybe_add_GSUB_feature (ruleset, info, script_index, FT_MAKE_TAG ('p','s','t','f'), pstf); maybe_add_GSUB_feature (ruleset, info, script_index, FT_MAKE_TAG ('p','r','e','s'), pres); maybe_add_GSUB_feature (ruleset, info, script_index, FT_MAKE_TAG ('b','l','w','s'), blws); maybe_add_GSUB_feature (ruleset, info, script_index, FT_MAKE_TAG ('a','b','v','s'), abvs); maybe_add_GSUB_feature (ruleset, info, script_index, FT_MAKE_TAG ('p','s','t','s'), psts); maybe_add_GSUB_feature (ruleset, info, script_index, FT_MAKE_TAG ('c','l','i','g'), clig); } if (pango_ot_info_find_script (info, PANGO_OT_TABLE_GPOS, tibetan_tag, &script_index)) { maybe_add_GPOS_feature (ruleset, info, script_index, FT_MAKE_TAG ('d','i','s','t'), dist); maybe_add_GPOS_feature (ruleset, info, script_index, FT_MAKE_TAG ('b','l','w','m'), blwm); maybe_add_GPOS_feature (ruleset, info, script_index, FT_MAKE_TAG ('a','b','v','m'), abvm); maybe_add_GPOS_feature (ruleset, info, script_index, FT_MAKE_TAG ('m','k','m','k'), mkmk); } g_object_set_qdata_full (G_OBJECT (info), ruleset_quark, ruleset, (GDestroyNotify)g_object_unref); } return ruleset; } static PangoGlyph get_index (PangoFcFont *fc_font, gunichar wc) { PangoGlyph index = pango_fc_font_get_glyph (fc_font, wc); if (!index) index = PANGO_GET_UNKNOWN_GLYPH ( wc); return index; } static void tibetan_engine_shape (PangoEngineShape *engine, PangoFont *font, const char *text, int length, const PangoAnalysis *analysis, PangoGlyphString *glyphs) { PangoFcFont *fc_font; FT_Face face; PangoOTRuleset *ruleset; PangoOTBuffer *buffer; glong n_chars; gunichar *wcs; const char *p; int i; glong syllable; TibetanCharClass charClass; glong cursor = 0; g_return_if_fail (font != NULL); g_return_if_fail (text != NULL); g_return_if_fail (length >= 0); g_return_if_fail (analysis != NULL); fc_font = PANGO_FC_FONT (font); face = pango_fc_font_lock_face (fc_font); if (!face) return; buffer = pango_ot_buffer_new (fc_font); wcs = g_utf8_to_ucs4_fast (text, length, &n_chars); p = text; /* This loop only exits when we reach the end of a run, which may contain * several syllables. */ while (cursor < n_chars) { syllable = find_syllable (wcs, cursor, n_chars); /* shall we add a dotted circle? * If in the position in which the base should be (first char in the string) there is * a character that has the Dotted circle flag (a character that cannot be a base) * then write a dotted circle */ if (get_char_class (wcs[cursor]) & CF_DOTTED_CIRCLE) { pango_ot_buffer_add_glyph (buffer, get_index (fc_font, C_DOTTED_CIRCLE), default_p, p - text); } /* If it encounters a digit followed by number pre combining mark, then reorder the two characters * coeng Ro if they are present */ for (i = cursor; i < syllable; i += 1) { charClass = get_char_class (wcs[i]); if ((charClass & CF_DIGIT ) && ( get_char_class (wcs[i+1]) & CF_PREDIGIT)) { pango_ot_buffer_add_glyph (buffer, get_index (fc_font, C_PRE_NUMBER_MARK), pref_p, p - text); p = g_utf8_next_char (p); pango_ot_buffer_add_glyph (buffer, get_index (fc_font, wcs[i]), pref_p, p - text); i += 1; } else { switch (charClass & CF_POS_MASK) { case CF_POS_ABOVE : pango_ot_buffer_add_glyph (buffer, get_index (fc_font, wcs[i]), abvf_p, p - text); break; case CF_POS_AFTER : pango_ot_buffer_add_glyph (buffer, get_index (fc_font, wcs[i]), pstf_p, p - text); break; case CF_POS_BELOW : pango_ot_buffer_add_glyph (buffer, get_index (fc_font, wcs[i]), blwf_p, p - text); break; default: /* default - any other characters */ pango_ot_buffer_add_glyph (buffer, get_index (fc_font, wcs[i]), default_p, p - text); break; } /* switch */ } p = g_utf8_next_char (p); } /* for */ cursor = syllable; /* move the pointer to the start of next syllable */ } /* while */ /* do gsub processing */ ruleset = get_ruleset (face); if (ruleset != NULL) { pango_ot_ruleset_substitute (ruleset, buffer); pango_ot_ruleset_position (ruleset, buffer); } pango_ot_buffer_output (buffer, glyphs); g_free (wcs); pango_ot_buffer_destroy (buffer); pango_fc_font_unlock_face (fc_font); } static void tibetan_engine_fc_class_init (PangoEngineShapeClass *class) { class->script_shape = tibetan_engine_shape; } PANGO_ENGINE_SHAPE_DEFINE_TYPE (TibetanEngineFc, tibetan_engine_fc, tibetan_engine_fc_class_init, NULL) void PANGO_MODULE_ENTRY(init) (GTypeModule *module) { tibetan_engine_fc_register_type (module); } void PANGO_MODULE_ENTRY(exit) (void) { } void PANGO_MODULE_ENTRY(list) (PangoEngineInfo **engines, int *n_engines) { *engines = script_engines; *n_engines = G_N_ELEMENTS (script_engines); } PangoEngine * PANGO_MODULE_ENTRY(create) (const char *id) { if (!strcmp (id, SCRIPT_ENGINE_NAME)) return g_object_new (tibetan_engine_fc_type, NULL); else return NULL; }