Add simple tibetan module. (#148566, G Karunakar)

Wed Dec 15 11:15:37 2004  Owen Taylor  <otaylor@redhat.com>

        * configure.in modules/Makefile.am modules/tibetan/*:
        Add simple tibetan module. (#148566, G Karunakar)

3 files changed, 359 insertions, 0 deletions

diff --git a/modules/tibetan/.cvsignore b/modules/tibetan/.cvsignore
new file mode 100644
index 00000000..282522db
--- /dev/null
+++ b/modules/tibetan/.cvsignore
@@ -0,0 +1,2 @@
+Makefile
+Makefile.in
diff --git a/modules/tibetan/Makefile.am b/modules/tibetan/Makefile.am
new file mode 100644
index 00000000..e4f3096f
--- /dev/null
+++ b/modules/tibetan/Makefile.am
@@ -0,0 +1,42 @@
+## Process this file with automake to create Makefile.in.
+
+pangolibs = $(top_builddir)/pango/libpango-$(PANGO_API_VERSION).la $(GLIB_LIBS)
+pangoft2libs = $(top_builddir)/pango/libpangoft2-$(PANGO_API_VERSION).la $(FREETYPE_LIBS) $(pangolibs)
+
+INCLUDES =			\
+	-DPANGO_ENABLE_ENGINE	\
+	-DG_DISABLE_DEPRECATED	\
+	$(PANGO_DEBUG_FLAGS)	\
+	-I$(top_srcdir)		\
+	-I$(top_srcdir)/pango/	\
+	$(GLIB_CFLAGS)
+
+if PLATFORM_WIN32
+no_undefined = -no-undefined
+endif
+
+moduledir = $(libdir)/pango/$(PANGO_MODULE_VERSION)/modules
+module_LTLIBRARIES =
+noinst_LTLIBRARIES =
+
+if HAVE_FREETYPE
+INCLUDES += $(FREETYPE_CFLAGS)
+if INCLUDE_TIBETAN_FC
+noinst_LTLIBRARIES += libpango-tibetan-fc.la
+else
+module_LTLIBRARIES += pango-tibetan-fc.la
+endif
+endif
+
+tibetan_fc_sources = $(common_sources) tibetan-fc.c
+
+pango_tibetan_fc_la_LDFLAGS = -export-dynamic -avoid-version -module $(no_undefined)
+pango_tibetan_fc_la_LIBADD = $(pangoft2libs)
+pango_tibetan_fc_la_SOURCES = $(tibetan_fc_sources)
+libpango_tibetan_fc_la_SOURCES = $(tibetan_fc_sources)
+libpango_tibetan_fc_la_CFLAGS = -DPANGO_MODULE_PREFIX=_pango_tibetan_fc
+
+
+included-modules: $(noinst_LTLIBRARIES)
+
+.PHONY: included-modules
diff --git a/modules/tibetan/tibetan-fc.c b/modules/tibetan/tibetan-fc.c
new file mode 100644
index 00000000..642f9f87
--- /dev/null
+++ b/modules/tibetan/tibetan-fc.c
@@ -0,0 +1,315 @@
+/* Pango
+ * tibetan-fc.c: Shaper for Tibetan script
+ * based on thai-fc.c and basic-fc.c
+ *
+ * Copyright (C) 1999-2004 Red Hat Software
+ * Author: Owen Taylor <otaylor@redhat.com>
+ *
+ * Copyright (C) 2004 Theppitak Karoonboonyanan <thep@linux.thai.net>
+ *
+ * Copyright (C) 2004 G Karunakar <karunakar@freedomink.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 <string.h>
+
+#include <glib.h>
+#include <pango-engine.h>
+#include "pango-ot.h"
+#include "pangofc-font.h"
+
+typedef PangoEngineShape	TibetanEngineFc;
+typedef PangoEngineShapeClass	TibetanEngineFcClass;
+
+#define SCRIPT_ENGINE_NAME "TibetanScriptEngineFc"
+#define RENDER_TYPE PANGO_RENDER_TYPE_FC
+
+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)
+  }
+};
+
+/* GPOS tables are not present in Joyig font */
+#undef DO_GPOS
+
+static void
+maybe_add_gsub_feature (PangoOTRuleset *ruleset,
+			PangoOTInfo    *info,
+			guint           script_index,
+			PangoOTTag      feature_tag,
+			gulong          property_bit)
+{
+  guint feature_index;
+  
+  /* 0xffff == default language system */
+  if (pango_ot_info_find_feature (info, PANGO_OT_TABLE_GSUB,
+				  feature_tag, script_index, 0xffff, &feature_index))
+    {
+      pango_ot_ruleset_add_feature (ruleset, PANGO_OT_TABLE_GSUB, feature_index,
+				    property_bit);
+    }
+}
+
+#ifdef DO_GPOS
+static void
+maybe_add_gpos_feature (PangoOTRuleset *ruleset,
+		        PangoOTInfo    *info,
+			guint           script_index,
+			PangoOTTag      feature_tag,
+			gulong          property_bit)
+{
+  guint feature_index;
+
+  if (pango_ot_info_find_feature (info, PANGO_OT_TABLE_GPOS,
+				  feature_tag, script_index, 0xffff, &feature_index))
+    {
+      pango_ot_ruleset_add_feature (ruleset, PANGO_OT_TABLE_GPOS, feature_index,
+				    property_bit);
+    }
+}
+#endif
+
+static PangoOTRuleset *
+get_gsub_ruleset (FT_Face face)
+{
+  PangoOTInfo    *info = pango_ot_info_get (face);
+  GQuark          ruleset_quark = g_quark_from_string ("tibetan-gsub-ruleset");
+  PangoOTRuleset *ruleset;
+
+  if (!info)
+    return NULL;
+
+  ruleset = g_object_get_qdata (G_OBJECT (info), ruleset_quark);
+
+  if (!ruleset)
+    {
+      PangoOTTag tibt_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,
+				     tibt_tag, &script_index))
+	{
+	  maybe_add_gsub_feature (ruleset, info, script_index, FT_MAKE_TAG ('c','c','m','p'), 0xFFFF);
+	  maybe_add_gsub_feature (ruleset, info, script_index, FT_MAKE_TAG ('b','l','w','s'), 0xFFFF);
+	  maybe_add_gsub_feature (ruleset, info, script_index, FT_MAKE_TAG ('a','b','v','s'), 0xFFFF);
+	}
+
+      g_object_set_qdata_full (G_OBJECT (info), ruleset_quark, ruleset,
+			       (GDestroyNotify)g_object_unref);
+    }
+
+  return ruleset;
+}
+
+static PangoOTRuleset *
+get_gpos_ruleset (FT_Face face)
+{
+#ifdef DO_GPOS
+  PangoOTInfo    *info = pango_ot_info_get (face);
+  GQuark          ruleset_quark = g_quark_from_string ("tibetan-gpos-ruleset");
+  PangoOTRuleset *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_GPOS,
+				     tibetan_tag, &script_index))
+	{
+	  maybe_add_gpos_feature (ruleset, info, script_index, FT_MAKE_TAG ('k','e','r','n'), 0xFFFF);
+	  maybe_add_gpos_feature (ruleset, info, script_index, FT_MAKE_TAG ('m','a','r','k'), 0xFFFF);
+	  maybe_add_gpos_feature (ruleset, info, script_index, FT_MAKE_TAG ('m','k','m','k'), 0xFFFF);
+	}
+
+      g_object_set_qdata_full (G_OBJECT (info), ruleset_quark, ruleset,
+			       (GDestroyNotify)g_object_unref);
+    }
+
+  return ruleset;
+#else
+  return NULL;
+#endif
+}
+
+static void
+set_glyph (PangoFont        *font,
+           PangoGlyphString *glyphs,
+           int               i,
+           int               offset,
+           PangoGlyph        glyph)
+{
+  PangoRectangle logical_rect;
+
+  glyphs->glyphs[i].glyph = glyph;
+  
+  glyphs->glyphs[i].geometry.x_offset = 0;
+  glyphs->glyphs[i].geometry.y_offset = 0;
+
+  glyphs->log_clusters[i] = offset;
+
+  pango_font_get_glyph_extents (font, glyphs->glyphs[i].glyph, NULL, 
+				&logical_rect);
+  glyphs->glyphs[i].geometry.width = logical_rect.width;
+}
+
+static void 
+fallback_shape (PangoFont        *font,
+		const char       *text,
+		gint              length,
+		PangoGlyphString *glyphs)
+{
+  PangoFcFont *fc_font = PANGO_FC_FONT (font);
+  const char *p;
+  long n_chars, i;
+
+  n_chars = g_utf8_strlen (text, length);
+  pango_glyph_string_set_size (glyphs, n_chars);
+  
+  for (i = 0, p = text; i < n_chars; i++, p = g_utf8_next_char (p))
+    {
+      gunichar wc;
+      PangoGlyph index;
+
+      wc = g_utf8_get_char (p);
+
+      index = pango_fc_font_get_glyph (fc_font, wc);
+      if (!index)
+	index = pango_fc_font_get_unknown_glyph (fc_font, wc);
+      
+      set_glyph (font, glyphs, i, p - text, index);
+    }
+}
+
+static void
+ot_shape (PangoFont        *font,
+	  PangoOTRuleset   *gsub_ruleset,
+	  PangoOTRuleset   *gpos_ruleset,
+	  const char       *text,
+	  gint              length,
+	  PangoGlyphString *glyphs)
+{
+  PangoFcFont *fc_font = PANGO_FC_FONT(font);
+  PangoOTBuffer *buffer = pango_ot_buffer_new (fc_font);
+  const char *p;
+  
+  for (p = text; p - text < length; p = g_utf8_next_char (p))
+    {
+      gunichar wc;
+      PangoGlyph index;
+      
+      wc = g_utf8_get_char (p);
+      
+      index = pango_fc_font_get_glyph (fc_font, wc);	  
+      if (!index)
+	index = pango_fc_font_get_unknown_glyph (fc_font, wc);
+      
+      pango_ot_buffer_add_glyph (buffer, index, 0, p - text);
+    }
+  
+  if (gsub_ruleset != NULL)
+    pango_ot_ruleset_substitute (gsub_ruleset, buffer);
+  
+  if (gpos_ruleset != NULL)
+    pango_ot_ruleset_position (gpos_ruleset, buffer);
+  
+  pango_ot_buffer_output (buffer, glyphs);
+  pango_ot_buffer_destroy (buffer);
+}
+
+static void
+tibetan_engine_shape (PangoEngineShape *engine,
+		      PangoFont        *font,
+		      const char       *text,
+		      int               length,
+		      PangoAnalysis    *analysis,
+		      PangoGlyphString *glyphs)
+{
+  PangoFcFont *fc_font = PANGO_FC_FONT(font);
+  PangoOTRuleset *gsub_ruleset;
+  PangoOTRuleset *gpos_ruleset;
+  FT_Face face;
+
+  g_return_if_fail (length >= 0);
+
+  face = pango_fc_font_lock_face (fc_font);
+  g_assert (face != NULL);
+  
+  gsub_ruleset = get_gsub_ruleset (face);
+  gpos_ruleset = get_gpos_ruleset (face);
+  
+  if (gsub_ruleset != NULL)
+    ot_shape (font, gsub_ruleset, gpos_ruleset, text, length, glyphs);
+  else
+    fallback_shape (font, text, length, glyphs);
+
+  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;
+}