diff options
Diffstat (limited to 'trunk/modules/arabic/arabic-fc.c')
| -rw-r--r-- | trunk/modules/arabic/arabic-fc.c | 224 |
1 files changed, 224 insertions, 0 deletions
diff --git a/trunk/modules/arabic/arabic-fc.c b/trunk/modules/arabic/arabic-fc.c new file mode 100644 index 00000000..5765982b --- /dev/null +++ b/trunk/modules/arabic/arabic-fc.c @@ -0,0 +1,224 @@ +/* Pango + * arabic-fc.c: Arabic shaper for FreeType-based backends + * + * Copyright (C) 2000, 2003, 2007 Red Hat Software + * Authors: + * Owen Taylor <otaylor@redhat.com> + * Behdad Esfahbod <behdad@behdad.org> + * + * 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. + */ + +#include <config.h> +#include <string.h> + +#include "arabic-ot.h" + +#include "pango-engine.h" +#include "pango-utils.h" +#include "pangofc-font.h" + +/* No extra fields needed */ +typedef PangoEngineShape ArabicEngineFc; +typedef PangoEngineShapeClass ArabicEngineFcClass ; + +#define SCRIPT_ENGINE_NAME "ArabicScriptEngineFc" +#define RENDER_TYPE PANGO_RENDER_TYPE_FC + +static PangoEngineScriptInfo arabic_scripts[] = { + { PANGO_SCRIPT_ARABIC, "*" }, + { PANGO_SCRIPT_NKO, "*" } +}; + +static PangoEngineInfo script_engines[] = { + { + SCRIPT_ENGINE_NAME, + PANGO_ENGINE_TYPE_SHAPE, + RENDER_TYPE, + arabic_scripts, G_N_ELEMENTS(arabic_scripts) + } +}; + +static const PangoOTFeatureMap gsub_features[] = +{ + {"ccmp", PANGO_OT_ALL_GLYPHS}, + {"locl", PANGO_OT_ALL_GLYPHS}, + {"isol", isolated}, + {"fina", final}, + {"medi", medial}, + {"init", initial}, + {"rlig", PANGO_OT_ALL_GLYPHS}, + {"calt", PANGO_OT_ALL_GLYPHS}, + {"liga", PANGO_OT_ALL_GLYPHS}, + /* 'dlig' should be turned-on/off-able. lets turn off for now. */ + /* {"dlig", PANGO_OT_ALL_GLYPHS}, */ + {"cswh", PANGO_OT_ALL_GLYPHS}, + {"mset", PANGO_OT_ALL_GLYPHS} +}; + +static const PangoOTFeatureMap gpos_features[] = +{ + {"curs", PANGO_OT_ALL_GLYPHS}, + {"kern", PANGO_OT_ALL_GLYPHS}, + {"mark", PANGO_OT_ALL_GLYPHS}, + {"mkmk", PANGO_OT_ALL_GLYPHS} +}; + +static void +arabic_engine_shape (PangoEngineShape *engine, + PangoFont *font, + const char *text, + gint length, + const PangoAnalysis *analysis, + PangoGlyphString *glyphs) +{ + PangoFcFont *fc_font; + FT_Face face; + PangoOTRulesetDescription desc; + const PangoOTRuleset *ruleset; + PangoOTBuffer *buffer; + gulong *properties = NULL; + glong n_chars; + gunichar *wcs; + const char *p; + int cluster = 0; + gboolean rtl = analysis->level % 2 != 0; + int i; + + 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); + pango_ot_buffer_set_rtl (buffer, rtl); + pango_ot_buffer_set_zero_width_marks (buffer, TRUE); + + wcs = g_utf8_to_ucs4_fast (text, length, &n_chars); + properties = g_new0 (gulong, n_chars); + + Arabic_Assign_Properties (wcs, properties, n_chars, !rtl); + + g_free (wcs); + + p = text; + for (i=0; i < n_chars; i++) + { + gunichar wc; + PangoGlyph glyph; + + wc = g_utf8_get_char (p); + + if (g_unichar_type (wc) != G_UNICODE_NON_SPACING_MARK) + cluster = p - text; + + if (pango_is_zero_width (wc)) + glyph = PANGO_GLYPH_EMPTY; + else + { + gunichar c = wc; + + if (analysis->level % 2) + g_unichar_get_mirror_char (c, &c); + + /* Hack - Microsoft fonts are strange and don't contain the + * correct rules to shape ARABIC LETTER FARSI YEH in + * medial/initial position. It looks identical to ARABIC LETTER + * YEH in these positions, so we substitute if the font contains + * ARABIC LETTER YEH + */ + if (c == 0x6cc && + ((properties[i] & (initial | medial)) != (initial | medial)) && + pango_fc_font_has_char (fc_font, 0x64a)) + c = 0x64a; + + glyph = pango_fc_font_get_glyph (fc_font, c); + } + + if (!glyph) + glyph = PANGO_GET_UNKNOWN_GLYPH (wc); + + pango_ot_buffer_add_glyph (buffer, glyph, properties[i], cluster); + + p = g_utf8_next_char (p); + } + + g_free (properties); + + desc.script = analysis->script; + desc.language = analysis->language; + + desc.n_static_gsub_features = G_N_ELEMENTS (gsub_features); + desc.static_gsub_features = gsub_features; + desc.n_static_gpos_features = G_N_ELEMENTS (gpos_features); + desc.static_gpos_features = gpos_features; + + /* TODO populate other_features from analysis->extra_attrs */ + desc.n_other_features = 0; + desc.other_features = NULL; + + ruleset = pango_ot_ruleset_get_for_description (pango_ot_info_get (face), &desc); + + pango_ot_ruleset_substitute (ruleset, buffer); + pango_ot_ruleset_position (ruleset, buffer); + pango_ot_buffer_output (buffer, glyphs); + + pango_ot_buffer_destroy (buffer); + + pango_fc_font_unlock_face (fc_font); +} + +static void +arabic_engine_fc_class_init (PangoEngineShapeClass *class) +{ + class->script_shape = arabic_engine_shape; +} + +PANGO_ENGINE_SHAPE_DEFINE_TYPE (ArabicEngineFc, arabic_engine_fc, + arabic_engine_fc_class_init, NULL) + +void +PANGO_MODULE_ENTRY(init) (GTypeModule *module) +{ + arabic_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 (arabic_engine_fc_type, NULL); + else + return NULL; +} |