Since Xft may only be available statically without shlib deps, check for

Tue Dec 19 22:47:16 2000  Owen Taylor  <otaylor@redhat.com>

	* configure.in pango-config.in pangoxft.pc.in
	modules/basic/Makefile.am: Since Xft may only be available
	statically without shlib deps, check for FreeType libs explicitly
	and include them when linking, otherwise things won't work. Also,
	define FREETYPE_CFLAGS from freetype-config --cflags.

	* modules/basic/basic-xft.c pango/pangoxft-font{,map}.c: Fool
	Xft into not converting glyph indices by loading the
	face unencoded then calling FT_Set_Charmap ourselves.

	* pango/Makefile.am pango/pango-ot.h pango/opentype/* :Add start
	of opentype handling - most of the actually meat of the code here
	is the OpenType layout code from FreeType 1 ported to freetype2
	and adapted slighlty for our purposes.  Also, includes a
	incomplete OpenType-table-dumping code useful for figuring
	out what is going on.

	* pango/pangoxft.h pango/pangoxft-font.h: Add calls for
	getting FT_Face and PangoOTInfo from PangoXftFont.

	* modules/arabic/{Makefile.am,arabic-ot.[ch],arabic-xft.c}:
	Initial support for rendering Arabic with OpenType fonts.

8 files changed, 1211 insertions, 21 deletions

diff --git a/modules/arabic/Makefile.am b/modules/arabic/Makefile.am
index 9f6e538b..b276f02f 100644
--- a/modules/arabic/Makefile.am
+++ b/modules/arabic/Makefile.am
@@ -1,5 +1,11 @@
 ## Process this file with automake to create Makefile.in.
 
+if HAVE_XFT
+XFT_MODULES=pango-arabic-xft.la
+else
+XFT_MODULES=
+endif
+
 sources = \
 	arabic.c \
 	arconv.c \
@@ -16,14 +22,19 @@ noinst_LTLIBRARIES = libpango-arabic.la
 moddefine = -DMODULE_PREFIX
 else
 moduledir = $(libdir)/pango/modules
-module_LTLIBRARIES = pango-arabic.la
+module_LTLIBRARIES = $(XFT_MODULES) pango-arabic.la
 moduleflags = -rpath $(libdir)
 endif
 
-INCLUDES = -I$(top_srcdir) -I$(top_srcdir)/pango/ $(moddefine)
+INCLUDES = -I$(top_srcdir) -I$(top_srcdir)/pango/ $(moddefine) $(X_CFLAGS) $(FREETYPE_CFLAGS)
 
 pango_arabic_la_LDFLAGS = $(moduleflags) -export-dynamic -avoid-version -module
 pango_arabic_la_SOURCES = $(sources)
 
 libpango_arabic_la_SOURCES = $(sources)
 
+
+pango_arabic_xft_la_LDFLAGS = -rpath $(libdir) -export-dynamic -avoid-version -module
+pango_arabic_xft_la_LIBADD = 
+pango_arabic_xft_la_SOURCES = arabic-xft.c arabic-ot.c arabic-ot.h
+
diff --git a/modules/arabic/arabic-fc.c b/modules/arabic/arabic-fc.c
new file mode 100644
index 00000000..b8f7b5ad
--- /dev/null
+++ b/modules/arabic/arabic-fc.c
@@ -0,0 +1,358 @@
+/* Pango
+ * arabic-xft.h:
+ *
+ * Copyright (C) 2000 Red Hat Software
+ * Author: Owen Taylor <otaylor@redhat.com>
+ *
+ * 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 "arabic-ot.h"
+
+#include "pangoxft.h"
+#include "pango-utils.h"
+
+static PangoEngineRange arabic_ranges[] = {
+  /* Language characters */
+  { 0x060c, 0x06f9, "*" }, /* Arabic */
+};
+
+static PangoEngineInfo script_engines[] = {
+  {
+    "ArabicScriptEngineXft",
+    PANGO_ENGINE_TYPE_SHAPE,
+    PANGO_RENDER_TYPE_XFT,
+    arabic_ranges, G_N_ELEMENTS(arabic_ranges)
+  }
+};
+
+void
+maybe_add_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 PangoOTRuleset *
+get_ruleset (PangoFont *font)
+{
+  PangoOTRuleset *ruleset;
+  static GQuark ruleset_quark = 0;
+
+  PangoOTInfo *info = pango_xft_font_get_ot_info (font);
+
+  if (!ruleset_quark)
+    ruleset_quark = g_quark_from_string ("pango-arabic-ruleset");
+  
+  if (!info)
+    return NULL;
+
+  ruleset = g_object_get_qdata (G_OBJECT (font), ruleset_quark);
+
+  if (!ruleset)
+    {
+      PangoOTTag arab_tag = FT_MAKE_TAG ('a', 'r', 'a', 'b');
+      guint script_index;
+
+      ruleset = pango_ot_ruleset_new (info);
+
+      if (pango_ot_info_find_script (info, PANGO_OT_TABLE_GSUB,
+				     arab_tag, &script_index))
+	{
+	  maybe_add_feature (ruleset, info, script_index, FT_MAKE_TAG ('i','s','o','l'), isolated);
+	  maybe_add_feature (ruleset, info, script_index, FT_MAKE_TAG ('i','n','i','t'), initial);
+	  maybe_add_feature (ruleset, info, script_index, FT_MAKE_TAG ('m','e','d','i'), medial);
+	  maybe_add_feature (ruleset, info, script_index, FT_MAKE_TAG ('f','i','n','a'), final);
+	  maybe_add_feature (ruleset, info, script_index, FT_MAKE_TAG ('l','i','g','a'), 0xFFFF);
+	}
+
+      g_object_set_qdata_full (G_OBJECT (font), ruleset_quark, ruleset,
+			       (GDestroyNotify)g_object_unref);
+    }
+
+  return ruleset;
+}
+
+static void
+swap_range (PangoGlyphString *glyphs, int start, int end)
+{
+  int i, j;
+  
+  for (i = start, j = end - 1; i < j; i++, j--)
+    {
+      PangoGlyphInfo glyph_info;
+      gint log_cluster;
+      
+      glyph_info = glyphs->glyphs[i];
+      glyphs->glyphs[i] = glyphs->glyphs[j];
+      glyphs->glyphs[j] = glyph_info;
+      
+      log_cluster = glyphs->log_clusters[i];
+      glyphs->log_clusters[i] = glyphs->log_clusters[j];
+      glyphs->log_clusters[j] = log_cluster;
+    }
+}
+
+static void
+set_glyph (PangoFont *font, PangoGlyphString *glyphs, int i, int offset, PangoGlyph glyph)
+{
+  glyphs->glyphs[i].glyph = glyph;
+  glyphs->log_clusters[i] = offset;
+}
+
+static guint
+find_char (FT_Face face, PangoFont *font, gunichar wc)
+{
+  int index = FT_Get_Char_Index (face, wc);
+
+  if (index && index <= face->num_glyphs)
+    return index;
+  else
+    return 0;
+}
+
+static void 
+arabic_engine_shape (PangoFont        *font,
+		    const char       *text,
+		    gint              length,
+		    PangoAnalysis    *analysis,
+		    PangoGlyphString *glyphs)
+{
+  int n_chars;
+  int i;
+  const char *p;
+  gulong *properties = NULL;
+  gunichar *wcs = NULL;
+  FT_Face face;
+  PangoOTRuleset *ruleset;
+
+  g_return_if_fail (font != NULL);
+  g_return_if_fail (text != NULL);
+  g_return_if_fail (length >= 0);
+  g_return_if_fail (analysis != NULL);
+
+  face = pango_xft_font_get_face (font);
+  g_assert (face);
+
+  n_chars = g_utf8_strlen (text, length);
+  pango_glyph_string_set_size (glyphs, n_chars);
+
+  ruleset = get_ruleset (font);
+  if (ruleset)
+    {
+      wcs = g_utf8_to_ucs4 (text, length);
+      properties = g_new0 (gulong, n_chars);
+      
+      Assign_Arabic_Properties (wcs, properties, n_chars);
+    }
+  
+  p = text;
+  for (i=0; i < n_chars; i++)
+    {
+      gunichar wc;
+      gunichar mirrored_ch;
+      PangoGlyph index;
+      char buf[6];
+      const char *input;
+
+      wc = g_utf8_get_char (p);
+
+      input = p;
+      if (analysis->level % 2)
+	if (pango_get_mirror_char (wc, &mirrored_ch))
+	  {
+	    wc = mirrored_ch;
+	    
+	    g_unichar_to_utf8 (wc, buf);
+	    input = buf;
+	  }
+
+      if (wc >= 0x200B && wc <= 0x200F)	/* Zero-width characters */
+	{
+	  set_glyph (font, glyphs, i, p - text, 0);
+	}
+      else
+	{
+	  /* 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 (wc == 0x6cc && ruleset &&
+	      ((properties[i] & (initial | medial)) != (initial | medial)))
+	    wc = 0x64a;
+	  
+	  index = find_char (face, font, wc);
+
+	  if (!index)
+	    {
+	      set_glyph (font, glyphs, i, p - text,
+			 pango_xft_font_get_unknown_glyph (font, wc));
+	    }
+	  else
+	    {
+	      set_glyph (font, glyphs, i, p - text, index);
+	      
+	      if (g_unichar_type (wc) == G_UNICODE_NON_SPACING_MARK)
+		{
+		  if (i > 0)
+		    {
+		      glyphs->log_clusters[i] = glyphs->log_clusters[i-1];
+#if 0		      
+		      PangoRectangle logical_rect, ink_rect;
+		      
+		      glyphs->glyphs[i].geometry.width = MAX (glyphs->glyphs[i-1].geometry.width,
+							      glyphs->glyphs[i].geometry.width);
+		      glyphs->glyphs[i-1].geometry.width = 0;
+		      
+		      /* Some heuristics to try to guess how overstrike glyphs are
+		       * done and compensate
+		       */
+		      pango_font_get_glyph_extents (font, glyphs->glyphs[i].glyph, &ink_rect, &logical_rect);
+		      if (logical_rect.width == 0 && ink_rect.x == 0)
+			glyphs->glyphs[i].geometry.x_offset = (glyphs->glyphs[i].geometry.width - ink_rect.width) / 2;
+#endif
+		    }
+		}
+	    }
+	}
+      
+      p = g_utf8_next_char (p);
+    }
+
+  ruleset = get_ruleset (font);
+
+  if (ruleset)
+    {
+      pango_ot_ruleset_shape (ruleset, glyphs, properties);
+
+      g_free (wcs);
+      g_free (properties);
+
+    }
+
+  for (i = 0; i < glyphs->num_glyphs; i++)
+    {
+
+      if (glyphs->glyphs[i].glyph)
+	{
+	  PangoRectangle logical_rect;
+	  
+	  pango_font_get_glyph_extents (font, glyphs->glyphs[i].glyph, NULL, &logical_rect);
+	  glyphs->glyphs[i].geometry.width = logical_rect.width;
+	}
+      else
+	glyphs->glyphs[i].geometry.width = 0;
+  
+      glyphs->glyphs[i].geometry.x_offset = 0;
+      glyphs->glyphs[i].geometry.y_offset = 0;
+    }
+
+  /* Simple bidi support */
+
+  if (analysis->level % 2)
+    {
+      int start, end;
+
+      /* Swap all glyphs */
+      swap_range (glyphs, 0, glyphs->num_glyphs);
+      
+      /* Now reorder glyphs within each cluster back to LTR */
+      for (start=0; start<glyphs->num_glyphs;)
+	{
+	  end = start;
+	  while (end < glyphs->num_glyphs &&
+		 glyphs->log_clusters[end] == glyphs->log_clusters[start])
+	    end++;
+
+	  if (end > start + 1)
+	    swap_range (glyphs, start, end);
+	  start = end;
+	}
+    }
+}
+
+static PangoCoverage *
+arabic_engine_get_coverage (PangoFont  *font,
+			   const char *lang)
+{
+  return pango_font_get_coverage (font, lang);
+}
+
+static PangoEngine *
+arabic_engine_xft_new ()
+{
+  PangoEngineShape *result;
+  
+  result = g_new (PangoEngineShape, 1);
+
+  result->engine.id = PANGO_RENDER_TYPE_XFT;
+  result->engine.type = PANGO_ENGINE_TYPE_SHAPE;
+  result->engine.length = sizeof (result);
+  result->script_shape = arabic_engine_shape;
+  result->get_coverage = arabic_engine_get_coverage;
+
+  return (PangoEngine *)result;
+}
+
+/* The following three functions provide the public module API for
+ * Pango. If we are compiling it is a module, then we name the
+ * entry points script_engine_list, etc. But if we are compiling
+ * it for inclusion directly in Pango, then we need them to
+ * to have distinct names for this module, so we prepend
+ * _pango_arabic_
+ */
+#ifdef MODULE_PREFIX
+#define MODULE_ENTRY(func) _pango_arabic_##func
+#else
+#define MODULE_ENTRY(func) func
+#endif
+
+/* List the engines contained within this module
+ */
+void 
+MODULE_ENTRY(script_engine_list) (PangoEngineInfo **engines, gint *n_engines)
+{
+  *engines = script_engines;
+  *n_engines = G_N_ELEMENTS (script_engines);
+}
+
+/* Load a particular engine given the ID for the engine
+ */
+PangoEngine *
+MODULE_ENTRY(script_engine_load) (const char *id)
+{
+  if (!strcmp (id, "ArabicScriptEngineXft"))
+    return arabic_engine_xft_new ();
+  else
+    return NULL;
+}
+
+void 
+MODULE_ENTRY(script_engine_unload) (PangoEngine *engine)
+{
+}
diff --git a/modules/arabic/arabic-ot.c b/modules/arabic/arabic-ot.c
new file mode 100644
index 00000000..066e0a3e
--- /dev/null
+++ b/modules/arabic/arabic-ot.c
@@ -0,0 +1,384 @@
+/* This file is taken from the FreeType (1) tree. It's been reindented
+ * to roughly match Pango guidelines (in anticipation of future changes),
+ * but not otherwise much altered.
+ */
+
+/****************************************************************************/
+/*                                                                          */
+/*  The FreeType project -- a free and portable quality TrueType renderer.  */
+/*                                                                          */
+/*  Copyright 1996-2000 by                                                  */
+/*  D. Turner, R.Wilhelm, and W. Lemberg                                    */
+/*                                                                          */
+/*  arabic -- An implementation of the contextual algorithm given in the    */
+/*  Unicode 2.0 book to assign the `isolated', `initial', `medial', and     */
+/*  `final' properties to an input string of character codes for the Arabic */
+/*  script.                                                                 */
+/*                                                                          */
+/****************************************************************************/
+
+#include "arabic-ot.h"
+
+
+/*
+ *
+ *     Here a table of the joining classes for characters in the range
+ *     U+0620 - U+06FF.
+ *
+ *    The following character also has a joining class:
+ *
+ *     U+200C  ZERO WIDTH NON-JOINER  -> causing
+ *
+ *    All other characters are given the joining class `none'.
+ *
+ */
+
+joining_class  arabic[] =
+{
+  /* U+0620 */
+  none, none, right, right,
+  right, right, dual, right,
+  dual, right, dual, dual,
+  dual, dual, dual, right,
+
+  /* U+0630 */
+  right, right, right, dual,
+  dual, dual, dual, dual,
+  dual, dual, dual, none,
+  none, none, none, none,
+
+  /* U+0640 */
+  causing, dual, dual, dual,
+  dual, dual, dual, dual,
+  right, right, dual, transparent,
+  transparent, transparent, transparent, transparent,
+
+  /* U+0650 */
+  transparent, transparent, transparent, none,
+  none, none, none, none,
+  none, none, none, none,
+  none, none, none, none,
+
+  /* U+0660 */
+  none, none, none, none,
+  none, none, none, none,
+  none, none, none, none,
+  none, none, none, none,
+
+  /* U+0670 */
+  transparent, none, right, right,
+  none, right, right, right,
+  dual, dual, dual, dual,
+  dual, dual, dual, dual,
+
+  /* U+0680 */
+  dual, dual, dual, dual,
+  dual, dual, dual, dual,
+  right, right, right, right,
+  right, right, right, right,
+
+  /* U+0690 */
+  right, right, right, right,
+  right, right, right, right,
+  right, right, dual, dual,
+  dual, dual, dual, dual,
+
+  /* U+06A0 */
+  dual, dual, dual, dual,
+  dual, dual, dual, dual,
+  dual, dual, dual, dual,
+  dual, dual, dual, dual,
+
+  /* U+06B0 */
+  dual, dual, dual, dual,
+  dual, dual, dual, dual,
+  dual, dual, dual, dual,
+  dual, dual, dual, dual,
+
+  /* U+06C0 */
+  right, dual, right, right,
+  right, right, right, right,
+  right, right, right, right,
+  dual, right, dual, right,
+
+  /* U+06D0 */
+  dual, dual, right, right,
+  none, none, none, transparent,
+  transparent, transparent, transparent, transparent,
+  transparent, transparent, transparent, transparent,
+
+  /* U+06E0 */
+  transparent, transparent, transparent, transparent,
+  transparent, none, none, transparent,
+  transparent, none, transparent, transparent,
+  transparent, transparent, none, none,
+
+  /* U+06F0 */
+  none, none, none, none,
+  none, none, none, none,
+  none, none, dual, dual,
+  dual, none, none, none
+};
+
+#if 0
+struct cgc_
+{
+  FT_UShort  char_code;
+  FT_UShort  glyph_index;
+  FT_UShort  class;
+};
+
+typedef struct cgc_  cgc;
+
+int  compare_cgc (const void*  a,
+		  const void*  b)
+{
+  return (((cgc*)a)->glyph_index > ((cgc*)b)->glyph_index) ?
+    1 : ((((cgc*)a)->glyph_index == ((cgc*)b)->glyph_index) ?
+	  0 : -1);
+}
+
+
+TT_Error  Build_Arabic_Glyph_Properties (TT_CharMap        char_map,
+					 TT_UShort         max_glyphs,
+					 TTO_GDEFHeader**  gdef)
+{
+  TT_UShort  i, j, num_glyphs;
+
+  cgc        Arabic[0x0700 - 0x0620];
+
+  TT_UShort  glyph_indices[0x700 - 0x0620];
+  TT_UShort  classes[0x700 - 0x0620];
+
+  if (!gdef)
+    return TT_Err_Invalid_Argument;
+
+  j = 0;
+
+  for (i = 0x0620; i < 0x0700; i++)
+    {
+      Arabic[j].char_code   = i;
+      Arabic[j].class       = (arabic[i - 0x0620] == transparent) ?
+	MARK_GLYPH : SIMPLE_GLYPH;
+      Arabic[j].glyph_index = TT_Char_Index (char_map, i);
+      if (Arabic[j].glyph_index)
+        j++;
+    }
+  num_glyphs = j;
+
+  if (!num_glyphs)
+    {
+      /* no Arabic font */
+      *gdef = NULL;
+      return TT_Err_Ok;
+    }
+
+  /* sort it */
+
+  qsort (Arabic, num_glyphs, sizeof (cgc), compare_cgc);
+
+  /* write it to the arrays, removing duplicates */
+
+  glyph_indices[0] = Arabic[0].glyph_index;
+  classes[0]       = Arabic[0].class;
+
+  j = 1;
+
+  for (i = 1; i < num_glyphs; i++)
+    {
+      glyph_indices[j] = Arabic[i].glyph_index;
+      classes[j]       = Arabic[i].class;
+
+      if (glyph_indices[j - 1] != glyph_indices[j])
+        j++;
+    }
+  num_glyphs = j;
+
+  TT_GDEF_Build_ClassDefinition (*gdef, max_glyphs, num_glyphs,
+				 glyph_indices, classes);
+
+  return TT_Err_Ok;
+}
+#endif
+
+/* The joining rules as given in the Unicode 2.0 book (characters are
+ * here specified as appearing in the byte stream, i.e. *not* in
+ * visual order).  Joining classes are given in angle brackets, glyph
+ * forms in square brackets.  Glyphs affected by a specific rule are
+ * enclosed with vertical bars.
+ *
+ * Note: The description of the joining algorithm in the book is
+ *       severely broken.  You can get a corrected version from
+ *       www.unicode.org (as of 29-Jun-1999, this hasn't appeared).
+ *
+ *   R1: <anything1> <transparent> <anything2>
+ *
+ *         apply joining rules for
+ *           <anything1> <anything2> -> [shape1] [shape2]
+ *
+ *       -> [shape1] [isolated] [shape2]
+ *
+ *   R2: <causing|left|dual> |<right>|
+ *
+ *       -> [final]
+ *
+ *   R3: |<left>| <causing|right|dual>
+ *
+ *       -> [initial]
+ *
+ *   R4: <causing|left|dual> |<dual>| <causing|right|dual>
+ *
+ *       -> [medial]
+ *
+ *   R5: <causing|left|dual> |<dual>| <!(causing|right|dual)>
+ *
+ *       -> [final]
+ *
+ *   R6: <!(causing|left|dual)> |<dual>| <causing|right|dual>
+ *
+ *       -> [initial]
+ *
+ *   R7: If R1-R6 fail:
+ *
+ *       <anything> -> [isolated]                                     
+ */
+
+/* `direction' can be -1, 0, or 1 to indicate the last non-transparent
+ * glyph, the current glyph, and the next non-transparent glyph,
+ * respectively.
+ */
+
+static joining_class  Get_Joining_Class (gunichar*   string,
+					 int         pos,
+					 int         length,
+					 int         direction)
+{
+  joining_class  j;
+
+
+  while (1)
+    {
+      if (pos == 0 && direction < 0)
+        return none;
+
+      pos += direction;
+
+      if (pos >= length)
+        return none;
+      
+      if (string[pos] < 0x0620 ||
+	  string[pos] >= 0x0700)
+	{
+	  if (string[pos] == 0x200C)
+	    return causing;
+	  else
+	    return none;
+	}
+      else
+        j =  arabic[string[pos] - 0x0620];
+      
+      if (!direction || j != transparent)
+        return j;
+    }
+}
+
+
+FT_Error  Assign_Arabic_Properties (gunichar    *string,
+				    gulong      *properties,
+				    int          length)
+{
+  joining_class  previous, current, next;
+
+  int      i;
+
+  if (!string || !properties || length == 0)
+    return FT_Err_Invalid_Argument;
+
+  for (i = 0; i < length; i++)
+    {
+      previous = Get_Joining_Class (string, i, length, -1);
+      current  = Get_Joining_Class (string, i, length,  0);
+      next     = Get_Joining_Class (string, i, length,  1);
+
+      /* R1 */
+
+      if (current == transparent)
+	{
+	  properties[i] |= isolated_p;
+	  continue;
+	}
+
+      /* R2 */
+
+      if (previous == causing ||
+	  previous == left    ||
+	  previous == dual   )
+        if (current == right)
+	  {
+	    properties[i] |= final_p;
+	    continue;
+	  }
+
+      /* R3 */
+
+      if (current == left)
+        if (next == causing ||
+	    next == right   ||
+	    next == dual   )
+	  {
+	    properties[i] |= initial_p;
+	    continue;
+	  }
+
+      /* R4 */
+
+      if (previous == causing ||
+	  previous == left    ||
+	  previous == dual   )
+        if (current == dual)
+          if (next == causing ||
+	      next == right   ||
+	      next == dual   )
+	    {
+	      properties[i] |= medial_p;
+	      continue;
+	    }
+
+      /* R5 */
+
+      if (previous == causing ||
+	  previous == left    ||
+	  previous == dual   )
+        if (current == dual)
+          if (!(next == causing ||
+		next == right   ||
+		next == dual   ))
+	    {
+	      properties[i] |= final_p;
+	      continue;
+	    }
+
+      /* R6 */
+
+      if (!(previous == causing ||
+	    previous == left    ||
+	    previous == dual   ))
+        if (current == dual)
+          if (next == causing ||
+	      next == right   ||
+	      next == dual   )
+	    {
+	      properties[i] |= initial_p;
+	      continue;
+	    }
+
+      /* R7 */
+
+      properties[i] |= isolated_p;
+    }
+
+  return FT_Err_Ok;
+}
+
+
+/* End */
diff --git a/modules/arabic/arabic-ot.h b/modules/arabic/arabic-ot.h
new file mode 100644
index 00000000..63b79199
--- /dev/null
+++ b/modules/arabic/arabic-ot.h
@@ -0,0 +1,72 @@
+/* This file is taken from the FreeType (1) tree. It's been reindented
+ * to roughly match Pango guidelines (in anticipation of future changes),
+ * but not otherwise much altered.
+ */
+
+/****************************************************************************/
+/*                                                                          */
+/*  The FreeType project -- a free and portable quality TrueType renderer.  */
+/*                                                                          */
+/*  Copyright 1996-2000 by                                                  */
+/*  D. Turner, R.Wilhelm, and W. Lemberg                                    */
+/*                                                                          */
+/*  arabic -- An implementation of the contextual algorithm given in the    */
+/*  Unicode 2.0 book to assign the `isolated', `initial', `medial', and     */
+/*  `final' properties to an input string of character codes for the Arabic */
+/*  script.                                                                 */
+/*                                                                          */
+/****************************************************************************/
+
+
+#include <pango/pango-ot.h>
+
+
+enum  joining_type_
+{
+  isolated = 1,       /* nominal        */
+  final    = 2,       /* right_joining  */
+  initial  = 4,       /* left_joining   */
+  medial   = 8        /* double_joining */
+};
+
+typedef enum joining_type_  joining_type;
+
+
+  /* A glyph's property value as needed by e.g. TT_GSUB_Apply_String()
+     specifies which features should *not* be applied                  */
+
+enum  arabic_glyph_property_
+{
+  isolated_p = final    | initial | medial,
+  final_p    = isolated | initial | medial,
+  initial_p  = isolated | final   | medial,
+  medial_p   = isolated | final   | initial
+};
+
+typedef enum arabic_glyph_property_  arabic_glyph_property;
+
+
+enum  joining_class_
+{
+  right,
+  left,               /* not used */
+  dual,
+  causing,
+  none,
+  transparent
+};
+
+typedef enum joining_class_  joining_class;
+
+
+FT_Error  Assign_Arabic_Properties (gunichar   *string,
+				    gulong     *properties,
+				    int         length);
+#if 0
+TT_Error  Build_Arabic_Glyph_Properties (TT_CharMap        char_map,
+					 TT_UShort         max_glyphs,
+					 TTO_GDEFHeader**  gdef );
+#endif
+
+
+/* End */
diff --git a/modules/arabic/arabic-xft.c b/modules/arabic/arabic-xft.c
new file mode 100644
index 00000000..b8f7b5ad
--- /dev/null
+++ b/modules/arabic/arabic-xft.c
@@ -0,0 +1,358 @@
+/* Pango
+ * arabic-xft.h:
+ *
+ * Copyright (C) 2000 Red Hat Software
+ * Author: Owen Taylor <otaylor@redhat.com>
+ *
+ * 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 "arabic-ot.h"
+
+#include "pangoxft.h"
+#include "pango-utils.h"
+
+static PangoEngineRange arabic_ranges[] = {
+  /* Language characters */
+  { 0x060c, 0x06f9, "*" }, /* Arabic */
+};
+
+static PangoEngineInfo script_engines[] = {
+  {
+    "ArabicScriptEngineXft",
+    PANGO_ENGINE_TYPE_SHAPE,
+    PANGO_RENDER_TYPE_XFT,
+    arabic_ranges, G_N_ELEMENTS(arabic_ranges)
+  }
+};
+
+void
+maybe_add_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 PangoOTRuleset *
+get_ruleset (PangoFont *font)
+{
+  PangoOTRuleset *ruleset;
+  static GQuark ruleset_quark = 0;
+
+  PangoOTInfo *info = pango_xft_font_get_ot_info (font);
+
+  if (!ruleset_quark)
+    ruleset_quark = g_quark_from_string ("pango-arabic-ruleset");
+  
+  if (!info)
+    return NULL;
+
+  ruleset = g_object_get_qdata (G_OBJECT (font), ruleset_quark);
+
+  if (!ruleset)
+    {
+      PangoOTTag arab_tag = FT_MAKE_TAG ('a', 'r', 'a', 'b');
+      guint script_index;
+
+      ruleset = pango_ot_ruleset_new (info);
+
+      if (pango_ot_info_find_script (info, PANGO_OT_TABLE_GSUB,
+				     arab_tag, &script_index))
+	{
+	  maybe_add_feature (ruleset, info, script_index, FT_MAKE_TAG ('i','s','o','l'), isolated);
+	  maybe_add_feature (ruleset, info, script_index, FT_MAKE_TAG ('i','n','i','t'), initial);
+	  maybe_add_feature (ruleset, info, script_index, FT_MAKE_TAG ('m','e','d','i'), medial);
+	  maybe_add_feature (ruleset, info, script_index, FT_MAKE_TAG ('f','i','n','a'), final);
+	  maybe_add_feature (ruleset, info, script_index, FT_MAKE_TAG ('l','i','g','a'), 0xFFFF);
+	}
+
+      g_object_set_qdata_full (G_OBJECT (font), ruleset_quark, ruleset,
+			       (GDestroyNotify)g_object_unref);
+    }
+
+  return ruleset;
+}
+
+static void
+swap_range (PangoGlyphString *glyphs, int start, int end)
+{
+  int i, j;
+  
+  for (i = start, j = end - 1; i < j; i++, j--)
+    {
+      PangoGlyphInfo glyph_info;
+      gint log_cluster;
+      
+      glyph_info = glyphs->glyphs[i];
+      glyphs->glyphs[i] = glyphs->glyphs[j];
+      glyphs->glyphs[j] = glyph_info;
+      
+      log_cluster = glyphs->log_clusters[i];
+      glyphs->log_clusters[i] = glyphs->log_clusters[j];
+      glyphs->log_clusters[j] = log_cluster;
+    }
+}
+
+static void
+set_glyph (PangoFont *font, PangoGlyphString *glyphs, int i, int offset, PangoGlyph glyph)
+{
+  glyphs->glyphs[i].glyph = glyph;
+  glyphs->log_clusters[i] = offset;
+}
+
+static guint
+find_char (FT_Face face, PangoFont *font, gunichar wc)
+{
+  int index = FT_Get_Char_Index (face, wc);
+
+  if (index && index <= face->num_glyphs)
+    return index;
+  else
+    return 0;
+}
+
+static void 
+arabic_engine_shape (PangoFont        *font,
+		    const char       *text,
+		    gint              length,
+		    PangoAnalysis    *analysis,
+		    PangoGlyphString *glyphs)
+{
+  int n_chars;
+  int i;
+  const char *p;
+  gulong *properties = NULL;
+  gunichar *wcs = NULL;
+  FT_Face face;
+  PangoOTRuleset *ruleset;
+
+  g_return_if_fail (font != NULL);
+  g_return_if_fail (text != NULL);
+  g_return_if_fail (length >= 0);
+  g_return_if_fail (analysis != NULL);
+
+  face = pango_xft_font_get_face (font);
+  g_assert (face);
+
+  n_chars = g_utf8_strlen (text, length);
+  pango_glyph_string_set_size (glyphs, n_chars);
+
+  ruleset = get_ruleset (font);
+  if (ruleset)
+    {
+      wcs = g_utf8_to_ucs4 (text, length);
+      properties = g_new0 (gulong, n_chars);
+      
+      Assign_Arabic_Properties (wcs, properties, n_chars);
+    }
+  
+  p = text;
+  for (i=0; i < n_chars; i++)
+    {
+      gunichar wc;
+      gunichar mirrored_ch;
+      PangoGlyph index;
+      char buf[6];
+      const char *input;
+
+      wc = g_utf8_get_char (p);
+
+      input = p;
+      if (analysis->level % 2)
+	if (pango_get_mirror_char (wc, &mirrored_ch))
+	  {
+	    wc = mirrored_ch;
+	    
+	    g_unichar_to_utf8 (wc, buf);
+	    input = buf;
+	  }
+
+      if (wc >= 0x200B && wc <= 0x200F)	/* Zero-width characters */
+	{
+	  set_glyph (font, glyphs, i, p - text, 0);
+	}
+      else
+	{
+	  /* 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 (wc == 0x6cc && ruleset &&
+	      ((properties[i] & (initial | medial)) != (initial | medial)))
+	    wc = 0x64a;
+	  
+	  index = find_char (face, font, wc);
+
+	  if (!index)
+	    {
+	      set_glyph (font, glyphs, i, p - text,
+			 pango_xft_font_get_unknown_glyph (font, wc));
+	    }
+	  else
+	    {
+	      set_glyph (font, glyphs, i, p - text, index);
+	      
+	      if (g_unichar_type (wc) == G_UNICODE_NON_SPACING_MARK)
+		{
+		  if (i > 0)
+		    {
+		      glyphs->log_clusters[i] = glyphs->log_clusters[i-1];
+#if 0		      
+		      PangoRectangle logical_rect, ink_rect;
+		      
+		      glyphs->glyphs[i].geometry.width = MAX (glyphs->glyphs[i-1].geometry.width,
+							      glyphs->glyphs[i].geometry.width);
+		      glyphs->glyphs[i-1].geometry.width = 0;
+		      
+		      /* Some heuristics to try to guess how overstrike glyphs are
+		       * done and compensate
+		       */
+		      pango_font_get_glyph_extents (font, glyphs->glyphs[i].glyph, &ink_rect, &logical_rect);
+		      if (logical_rect.width == 0 && ink_rect.x == 0)
+			glyphs->glyphs[i].geometry.x_offset = (glyphs->glyphs[i].geometry.width - ink_rect.width) / 2;
+#endif
+		    }
+		}
+	    }
+	}
+      
+      p = g_utf8_next_char (p);
+    }
+
+  ruleset = get_ruleset (font);
+
+  if (ruleset)
+    {
+      pango_ot_ruleset_shape (ruleset, glyphs, properties);
+
+      g_free (wcs);
+      g_free (properties);
+
+    }
+
+  for (i = 0; i < glyphs->num_glyphs; i++)
+    {
+
+      if (glyphs->glyphs[i].glyph)
+	{
+	  PangoRectangle logical_rect;
+	  
+	  pango_font_get_glyph_extents (font, glyphs->glyphs[i].glyph, NULL, &logical_rect);
+	  glyphs->glyphs[i].geometry.width = logical_rect.width;
+	}
+      else
+	glyphs->glyphs[i].geometry.width = 0;
+  
+      glyphs->glyphs[i].geometry.x_offset = 0;
+      glyphs->glyphs[i].geometry.y_offset = 0;
+    }
+
+  /* Simple bidi support */
+
+  if (analysis->level % 2)
+    {
+      int start, end;
+
+      /* Swap all glyphs */
+      swap_range (glyphs, 0, glyphs->num_glyphs);
+      
+      /* Now reorder glyphs within each cluster back to LTR */
+      for (start=0; start<glyphs->num_glyphs;)
+	{
+	  end = start;
+	  while (end < glyphs->num_glyphs &&
+		 glyphs->log_clusters[end] == glyphs->log_clusters[start])
+	    end++;
+
+	  if (end > start + 1)
+	    swap_range (glyphs, start, end);
+	  start = end;
+	}
+    }
+}
+
+static PangoCoverage *
+arabic_engine_get_coverage (PangoFont  *font,
+			   const char *lang)
+{
+  return pango_font_get_coverage (font, lang);
+}
+
+static PangoEngine *
+arabic_engine_xft_new ()
+{
+  PangoEngineShape *result;
+  
+  result = g_new (PangoEngineShape, 1);
+
+  result->engine.id = PANGO_RENDER_TYPE_XFT;
+  result->engine.type = PANGO_ENGINE_TYPE_SHAPE;
+  result->engine.length = sizeof (result);
+  result->script_shape = arabic_engine_shape;
+  result->get_coverage = arabic_engine_get_coverage;
+
+  return (PangoEngine *)result;
+}
+
+/* The following three functions provide the public module API for
+ * Pango. If we are compiling it is a module, then we name the
+ * entry points script_engine_list, etc. But if we are compiling
+ * it for inclusion directly in Pango, then we need them to
+ * to have distinct names for this module, so we prepend
+ * _pango_arabic_
+ */
+#ifdef MODULE_PREFIX
+#define MODULE_ENTRY(func) _pango_arabic_##func
+#else
+#define MODULE_ENTRY(func) func
+#endif
+
+/* List the engines contained within this module
+ */
+void 
+MODULE_ENTRY(script_engine_list) (PangoEngineInfo **engines, gint *n_engines)
+{
+  *engines = script_engines;
+  *n_engines = G_N_ELEMENTS (script_engines);
+}
+
+/* Load a particular engine given the ID for the engine
+ */
+PangoEngine *
+MODULE_ENTRY(script_engine_load) (const char *id)
+{
+  if (!strcmp (id, "ArabicScriptEngineXft"))
+    return arabic_engine_xft_new ();
+  else
+    return NULL;
+}
+
+void 
+MODULE_ENTRY(script_engine_unload) (PangoEngine *engine)
+{
+}
diff --git a/modules/basic/Makefile.am b/modules/basic/Makefile.am
index f0daa7ae..389013aa 100644
--- a/modules/basic/Makefile.am
+++ b/modules/basic/Makefile.am
@@ -18,7 +18,12 @@ module_LTLIBRARIES = $(XFT_MODULES) pango-basic.la
 moduleflags=-rpath $(libdir)
 endif
 
-INCLUDES = -I$(top_srcdir) -I$(top_srcdir)/pango/ $(X_CFLAGS) $(moddefine)
+INCLUDES = 			\
+	-I$(top_srcdir) 	\
+	-I$(top_srcdir)/pango/ 	\
+	$(X_CFLAGS) 		\
+	$(FREETYPE_CFLAGS)	\
+	$(moddefine)
 
 pango_basic_la_LDFLAGS = $(moduleflags) -export-dynamic -avoid-version -module
 pango_basic_la_LIBADD = 
diff --git a/modules/basic/basic-fc.c b/modules/basic/basic-fc.c
index 979a3772..746a687b 100644
--- a/modules/basic/basic-fc.c
+++ b/modules/basic/basic-fc.c
@@ -87,12 +87,12 @@ set_glyph (PangoFont *font, PangoGlyphString *glyphs, int i, int offset, PangoGl
 }
 
 static guint
-find_char (Display *display, PangoFont *font, gunichar wc)
+find_char (FT_Face face, PangoFont *font, gunichar wc)
 {
-  XftFont *xft_font = pango_xft_font_get_font (font);
+  int index = FT_Get_Char_Index (face, wc);
 
-  if (XftGlyphExists (display, xft_font, wc))
-    return wc;
+  if (index && index <= face->num_glyphs)
+    return index;
   else
     return 0;
 }
@@ -107,14 +107,15 @@ basic_engine_shape (PangoFont        *font,
   int n_chars;
   int i;
   const char *p;
-  Display *display;
+  FT_Face face;
 
   g_return_if_fail (font != NULL);
   g_return_if_fail (text != NULL);
   g_return_if_fail (length >= 0);
   g_return_if_fail (analysis != NULL);
 
-  display = pango_xft_font_get_display (font);
+  face = pango_xft_font_get_face (font);
+  g_assert (face);
   
   n_chars = g_utf8_strlen (text, length);
   pango_glyph_string_set_size (glyphs, n_chars);
@@ -140,13 +141,13 @@ basic_engine_shape (PangoFont        *font,
 	    input = buf;
 	  }
 
-      if (wc == 0x200B || wc == 0x200E || wc == 0x200F)	/* Zero-width characters */
+      if (wc >= 0x200B && wc <= 0x200F)	/* Zero-width characters */
 	{
 	  set_glyph (font, glyphs, i, p - text, 0);
 	}
       else
 	{
-	  index = find_char (display, font, wc);
+	  index = find_char (face, font, wc);
 
 	  if (!index)
 	    {
@@ -165,7 +166,7 @@ basic_engine_shape (PangoFont        *font,
 	      for (j=0; j < len; j++)
 		{
 		  set_glyph (font, glyphs, i + j,
-			     p - text, find_char (display, font, buf[j]));
+			     p - text, find_char (face, font, buf[j]));
 		}
 	      i += len - 1;
 #endif
diff --git a/modules/basic/basic-xft.c b/modules/basic/basic-xft.c
index 979a3772..746a687b 100644
--- a/modules/basic/basic-xft.c
+++ b/modules/basic/basic-xft.c
@@ -87,12 +87,12 @@ set_glyph (PangoFont *font, PangoGlyphString *glyphs, int i, int offset, PangoGl
 }
 
 static guint
-find_char (Display *display, PangoFont *font, gunichar wc)
+find_char (FT_Face face, PangoFont *font, gunichar wc)
 {
-  XftFont *xft_font = pango_xft_font_get_font (font);
+  int index = FT_Get_Char_Index (face, wc);
 
-  if (XftGlyphExists (display, xft_font, wc))
-    return wc;
+  if (index && index <= face->num_glyphs)
+    return index;
   else
     return 0;
 }
@@ -107,14 +107,15 @@ basic_engine_shape (PangoFont        *font,
   int n_chars;
   int i;
   const char *p;
-  Display *display;
+  FT_Face face;
 
   g_return_if_fail (font != NULL);
   g_return_if_fail (text != NULL);
   g_return_if_fail (length >= 0);
   g_return_if_fail (analysis != NULL);
 
-  display = pango_xft_font_get_display (font);
+  face = pango_xft_font_get_face (font);
+  g_assert (face);
   
   n_chars = g_utf8_strlen (text, length);
   pango_glyph_string_set_size (glyphs, n_chars);
@@ -140,13 +141,13 @@ basic_engine_shape (PangoFont        *font,
 	    input = buf;
 	  }
 
-      if (wc == 0x200B || wc == 0x200E || wc == 0x200F)	/* Zero-width characters */
+      if (wc >= 0x200B && wc <= 0x200F)	/* Zero-width characters */
 	{
 	  set_glyph (font, glyphs, i, p - text, 0);
 	}
       else
 	{
-	  index = find_char (display, font, wc);
+	  index = find_char (face, font, wc);
 
 	  if (!index)
 	    {
@@ -165,7 +166,7 @@ basic_engine_shape (PangoFont        *font,
 	      for (j=0; j < len; j++)
 		{
 		  set_glyph (font, glyphs, i + j,
-			     p - text, find_char (display, font, buf[j]));
+			     p - text, find_char (face, font, buf[j]));
 		}
 	      i += len - 1;
 #endif