Start implementation of CoreText backend

On Mac OS X systems where CoreText is available (that is, 10.5 or
higher), we will build the CoreText backend instead of the ATSUI
backend.  In this case, the ATSUI backend will not be built and
installed.  This change is necessary because since Mac OS 10.5
ATSUI has been marked as deprecated.

For older systems, we will have to continue to use the
ATSUI backend.

2 files changed, 249 insertions, 0 deletions

diff --git a/modules/basic/Makefile.am b/modules/basic/Makefile.am
index 93604c9e..a264d704 100644
--- a/modules/basic/Makefile.am
+++ b/modules/basic/Makefile.am
@@ -54,6 +54,16 @@ libpango_basic_win32_la_SOURCES = basic-win32.c
 libpango_basic_win32_la_CFLAGS = -DPANGO_MODULE_PREFIX=_pango_basic_win32
 
 if HAVE_CAIRO_ATSUI
+if HAVE_CORE_TEXT
+INCLUDES += $(CAIRO_CFLAGS)
+if INCLUDE_BASIC_CORE_TEXT
+noinst_LTLIBRARIES += libpango-basic-coretext.la
+else
+if DYNAMIC_BASIC_CORE_TEXT
+module_LTLIBRARIES += pango-basic-coretext.la
+endif
+endif
+else
 INCLUDES += $(ATSUI_CFLAGS) $(CAIRO_CFLAGS)
 if INCLUDE_BASIC_ATSUI
 noinst_LTLIBRARIES += libpango-basic-atsui.la
@@ -63,6 +73,13 @@ module_LTLIBRARIES += pango-basic-atsui.la
 endif
 endif
 endif
+endif
+
+pango_basic_coretext_la_LDFLAGS = -module $(MODULE_LIBTOOL_OPTIONS) -framework Carbon
+pango_basic_coretext_la_LIBADD = $(pangocoretextlibs)
+pango_basic_coretext_la_SOURCES = basic-coretext.c
+libpango_basic_coretext_la_SOURCES = basic-coretext.c
+libpango_basic_coretext_la_CFLAGS = -DPANGO_MODULE_PREFIX=_pango_basic_coretext
 
 pango_basic_atsui_la_LDFLAGS = -module $(MODULE_LIBTOOL_OPTIONS) -framework Carbon
 pango_basic_atsui_la_LIBADD = $(pangoatsuilibs)
diff --git a/modules/basic/basic-coretext.c b/modules/basic/basic-coretext.c
new file mode 100644
index 00000000..16707102
--- /dev/null
+++ b/modules/basic/basic-coretext.c
@@ -0,0 +1,232 @@
+/* Pango
+ * basic-coretext.c
+ *
+ * Copyright (C) 2005 Imendio AB
+ * Copyright (C) 2010  Kristian Rietveld  <kris@gtk.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 <glib.h>
+#include <string.h>
+#include <Carbon/Carbon.h>
+#include "pango-engine.h"
+#include "pango-utils.h"
+#include "pango-fontmap.h"
+#include "pangocoretext.h"
+
+/* No extra fields needed */
+typedef PangoEngineShape      BasicEngineCoreText;
+typedef PangoEngineShapeClass BasicEngineCoreTextClass ;
+
+#define SCRIPT_ENGINE_NAME "BasicScriptEngineCoreText"
+#define RENDER_TYPE PANGO_RENDER_TYPE_CORE_TEXT
+
+static PangoEngineScriptInfo basic_scripts[] = {
+  { PANGO_SCRIPT_COMMON,   "" }
+};
+
+static PangoEngineInfo script_engines[] = {
+  {
+    SCRIPT_ENGINE_NAME,
+    PANGO_ENGINE_TYPE_SHAPE,
+    RENDER_TYPE,
+    basic_scripts, G_N_ELEMENTS(basic_scripts)
+  }
+};
+
+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
+basic_engine_shape (PangoEngineShape    *engine,
+		    PangoFont           *font,
+		    const char          *text,
+		    gint                 length,
+		    const PangoAnalysis *analysis,
+		    PangoGlyphString    *glyphs)
+{
+  const char *p;
+  char *copy;
+  CTLineRef line;
+  CFStringRef cstr;
+  CFDictionaryRef attributes;
+  CFAttributedStringRef attstr;
+  PangoCoreTextFont *cfont = PANGO_CORE_TEXT_FONT (font);
+  PangoCoverage *coverage;
+  CFArrayRef runs;
+  CTRunRef run;
+  CFIndex i, glyph_count;
+  const CGGlyph *cgglyphs;
+
+  CFTypeRef keys[] = {
+      (CFTypeRef) kCTFontAttributeName
+  };
+
+  CFTypeRef values[] = {
+      pango_core_text_font_get_ctfont (cfont)
+  };
+
+  attributes = CFDictionaryCreate (kCFAllocatorDefault,
+                                   (const void **)keys,
+                                   (const void **)values,
+                                   1,
+                                   &kCFCopyStringDictionaryKeyCallBacks,
+                                   &kCFTypeDictionaryValueCallBacks);
+
+  copy = g_strndup (text, length + 1);
+  copy[length] = 0;
+
+  cstr = CFStringCreateWithCString (kCFAllocatorDefault, copy,
+                                    kCFStringEncodingUTF8);
+  g_free (copy);
+
+  attstr = CFAttributedStringCreate (kCFAllocatorDefault,
+                                     cstr,
+                                     attributes);
+
+  line = CTLineCreateWithAttributedString (attstr);
+
+  runs = CTLineGetGlyphRuns (line);
+
+  run = CFArrayGetValueAtIndex (runs, 0);
+  glyph_count = CTRunGetGlyphCount (run);
+  cgglyphs = CTRunGetGlyphsPtr (run);
+
+  p = text;
+  pango_glyph_string_set_size (glyphs, glyph_count);
+  coverage = pango_font_get_coverage (PANGO_FONT (cfont),
+                                      analysis->language);
+
+  for (i = 0; i < glyph_count; i++)
+    {
+      gunichar wc;
+      gunichar mirrored_ch;
+
+      wc = g_utf8_get_char (p);
+
+      if (analysis->level % 2)
+	if (pango_get_mirror_char (wc, &mirrored_ch))
+	  wc = mirrored_ch;
+
+      if (wc == 0xa0)	/* non-break-space */
+	wc = 0x20;
+
+      if (pango_is_zero_width (wc))
+	{
+	  set_glyph (font, glyphs, i, p - text, PANGO_GLYPH_EMPTY);
+	}
+      else
+	{
+          PangoCoverageLevel result;
+
+          result = pango_coverage_get (coverage, wc);
+
+          if (result != PANGO_COVERAGE_NONE)
+            {
+              set_glyph (font, glyphs, i, p - text, cgglyphs[i]);
+
+              if (g_unichar_type (wc) == G_UNICODE_NON_SPACING_MARK)
+                {
+                  if (i > 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;
+                      glyphs->log_clusters[i] = glyphs->log_clusters[i-1];
+
+                      /* 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;
+                    }
+                }
+            }
+          else
+            {
+              set_glyph (font, glyphs, i, p - text,
+                         PANGO_GET_UNKNOWN_GLYPH (wc));
+            }
+        }
+
+      p = g_utf8_next_char (p);
+    }
+
+  CFRelease (line);
+  CFRelease (attstr);
+  CFRelease (cstr);
+  CFRelease (attributes);
+  pango_coverage_unref (coverage);
+}
+
+static void
+basic_engine_core_text_class_init (PangoEngineShapeClass *class)
+{
+  class->script_shape = basic_engine_shape;
+}
+
+PANGO_ENGINE_SHAPE_DEFINE_TYPE (BasicEngineCoreText, basic_engine_core_text,
+				basic_engine_core_text_class_init, NULL);
+
+void
+PANGO_MODULE_ENTRY(init) (GTypeModule *module)
+{
+  basic_engine_core_text_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 (basic_engine_core_text_type, NULL);
+  else
+    return NULL;
+}
+