[gtk/wip/fanc999/fontchooser.win32.gtk3: 1/2] gtk/gtkfontchooserwidget.c: Support PangoWin32 fonts as well

[Chun-wei Fan <fanchunwei src gnome org>]

commit 9cdc9e9ac2e98359f430c371b3452a71b6b0f131
Author: Chun-wei Fan <fanchunwei src gnome org>
Date:   Mon Jan 7 15:39:30 2019 +0800

    gtk/gtkfontchooserwidget.c: Support PangoWin32 fonts as well
    
    The current font tweaking support here actually assumes that
    PangoFCFonts are used, which is not the case on Windows unless one
    specifically uses the FontConfig backend (set PANGOCAIRO_BACKEND=fc).
    This means that if GTK+ is build with HarfBuzz and PangoFT support
    enabled, the attempting to run the font tweaking support code on Windows
    will crash unless the FontConfig Pango backend is used.
    
    Use the utility code that we just added to support turning the
    PangoWin32Font into a FT_Face, so that we can load it using HarfBuzz,
    which is necessary before Pango is updated to use HarfBuzz for shaping
    on all supported backends at least.  This will also allow the font
    tweaking page to at least display properly even if GTK+ is not built
    with PangoFT support.
    
    Note that for the font tweaking updates to be applied, PangoWin32 needs
    to be updated as well, but at least for the GTK+ front this will pave
    the foundation for this.

 gtk/gtkfontchooserwidget.c | 62 ++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 51 insertions(+), 11 deletions(-)
---
diff --git a/gtk/gtkfontchooserwidget.c b/gtk/gtkfontchooserwidget.c
index b858d92c29..fc9e4631bd 100644
--- a/gtk/gtkfontchooserwidget.c
+++ b/gtk/gtkfontchooserwidget.c
@@ -25,6 +25,7 @@
 
 #include "gtkfontchooserwidget.h"
 #include "gtkfontchooserwidgetprivate.h"
+#include "gtkpangofontutilsprivate.h"
 
 #include "gtkadjustment.h"
 #include "gtkbuildable.h"
@@ -53,8 +54,8 @@
 #include "gtkcombobox.h"
 #include "gtkgesturemultipress.h"
 
-#if defined(HAVE_HARFBUZZ) && defined(HAVE_PANGOFT)
-#include <pango/pangofc-font.h>
+#ifdef HAVE_HARFBUZZ
+
 #include <hb.h>
 #include <hb-ot.h>
 #include <hb-ft.h>
@@ -140,6 +141,8 @@ struct _GtkFontChooserWidgetPrivate
   GList *feature_items;
 
   GAction *tweak_action;
+
+  gpointer ft_extra_items;
 };
 
 
@@ -761,7 +764,7 @@ change_tweak (GSimpleAction *action,
   g_simple_action_set_state (action, state);
 }
 
-#if defined(HAVE_HARFBUZZ) && defined(HAVE_PANGOFT)
+#ifdef HAVE_HARFBUZZ
 
 typedef struct {
   guint32 tag;
@@ -821,7 +824,7 @@ gtk_font_chooser_widget_init (GtkFontChooserWidget *fontchooser)
 
   gtk_widget_init_template (GTK_WIDGET (fontchooser));
 
-#if defined(HAVE_HARFBUZZ) && defined(HAVE_PANGOFT)
+#ifdef HAVE_HARFBUZZ
   priv->axes = g_hash_table_new_full (axis_hash, axis_equal, NULL, axis_free);
 #endif
 
@@ -862,7 +865,7 @@ gtk_font_chooser_widget_init (GtkFontChooserWidget *fontchooser)
 
   /* Load data and set initial style-dependent parameters */
   gtk_font_chooser_widget_load_fonts (fontchooser, TRUE);
-#if defined(HAVE_HARFBUZZ) && defined(HAVE_PANGOFT)
+#ifdef HAVE_HARFBUZZ
   gtk_font_chooser_widget_populate_features (fontchooser);
 #endif
   gtk_font_chooser_widget_set_cell_size (fontchooser);
@@ -1171,6 +1174,9 @@ gtk_font_chooser_widget_finalize (GObject *object)
 
   g_free (priv->font_features);
 
+  if (_gtk_pango_font_release_ft_items (priv->ft_extra_items))
+    g_free (priv->ft_extra_items);
+
   G_OBJECT_CLASS (gtk_font_chooser_widget_parent_class)->finalize (object);
 }
 
@@ -1442,7 +1448,7 @@ gtk_font_chooser_widget_ensure_selection (GtkFontChooserWidget *fontchooser)
     }
 }
 
-#if defined(HAVE_HARFBUZZ) && defined(HAVE_PANGOFT)
+#ifdef HAVE_HARFBUZZ
 
 /* OpenType variations */
 
@@ -1600,6 +1606,8 @@ gtk_font_chooser_widget_update_font_variations (GtkFontChooserWidget *fontchoose
   FT_MM_Var *ft_mm_var;
   FT_Error ret;
   gboolean has_axis = FALSE;
+  PangoFontMap *font_map = NULL;
+  gpointer ft_extra_items = NULL;
 
   if (priv->updating_variations)
     return FALSE;
@@ -1607,12 +1615,27 @@ gtk_font_chooser_widget_update_font_variations (GtkFontChooserWidget *fontchoose
   g_hash_table_foreach (priv->axes, axis_remove, NULL);
   g_hash_table_remove_all (priv->axes);
 
+
   if ((priv->level & GTK_FONT_CHOOSER_LEVEL_VARIATIONS) == 0)
     return FALSE;
 
   pango_font = pango_context_load_font (gtk_widget_get_pango_context (GTK_WIDGET (fontchooser)),
                                         priv->font_desc);
-  ft_face = pango_fc_font_lock_face (PANGO_FC_FONT (pango_font));
+
+  font_map = priv->font_map;
+  ft_extra_items = priv->ft_extra_items;
+
+  if (!font_map)
+    font_map = pango_cairo_font_map_get_default ();
+
+  if (!ft_extra_items)
+    {
+      ft_extra_items = _gtk_pango_font_init_extra_ft_items (pango_font);
+      if (ft_extra_items != NULL)
+        priv->ft_extra_items = ft_extra_items;
+    }
+
+  ft_face = _gtk_pango_font_get_ft_face (pango_font, font_map, ft_extra_items);
 
   ret = FT_Get_MM_Var (ft_face, &ft_mm_var);
   if (ret == 0)
@@ -1644,7 +1667,7 @@ gtk_font_chooser_widget_update_font_variations (GtkFontChooserWidget *fontchoose
       free (ft_mm_var);
     }
 
-  pango_fc_font_unlock_face (PANGO_FC_FONT (pango_font));
+  _gtk_pango_font_release_ft_face (pango_font, ft_extra_items);
   g_object_unref (pango_font);
 
   return has_axis;
@@ -2132,6 +2155,8 @@ gtk_font_chooser_widget_update_font_features (GtkFontChooserWidget *fontchooser)
   int i, j;
   GList *l;
   gboolean has_feature = FALSE;
+  PangoFontMap *font_map = NULL;
+  gpointer ft_extra_items = NULL;
 
   for (l = priv->feature_items; l; l = l->next)
     {
@@ -2145,7 +2170,22 @@ gtk_font_chooser_widget_update_font_features (GtkFontChooserWidget *fontchooser)
 
   pango_font = pango_context_load_font (gtk_widget_get_pango_context (GTK_WIDGET (fontchooser)),
                                         priv->font_desc);
-  ft_face = pango_fc_font_lock_face (PANGO_FC_FONT (pango_font)),
+
+  font_map = priv->font_map;
+  ft_extra_items = priv->ft_extra_items;
+
+  if (!font_map)
+    font_map = pango_cairo_font_map_get_default ();
+
+  if (!ft_extra_items)
+    {
+      ft_extra_items = _gtk_pango_font_init_extra_ft_items (pango_font);
+      if (ft_extra_items != NULL)
+        priv->ft_extra_items = ft_extra_items;
+    }
+
+  ft_face = _gtk_pango_font_get_ft_face (pango_font, font_map, ft_extra_items);
+
   hb_font = hb_ft_font_create (ft_face, NULL);
 
   if (hb_font)
@@ -2205,7 +2245,7 @@ gtk_font_chooser_widget_update_font_features (GtkFontChooserWidget *fontchooser)
       hb_face_destroy (hb_face);
     }
 
-  pango_fc_font_unlock_face (PANGO_FC_FONT (pango_font));
+  _gtk_pango_font_release_ft_face (pango_font, ft_extra_items);
   g_object_unref (pango_font);
 
   return has_feature;
@@ -2305,7 +2345,7 @@ gtk_font_chooser_widget_merge_font_desc (GtkFontChooserWidget       *fontchooser
 
       gtk_font_chooser_widget_update_marks (fontchooser);
 
-#if defined(HAVE_HARFBUZZ) && defined(HAVE_PANGOFT)
+#ifdef HAVE_HARFBUZZ
       if (gtk_font_chooser_widget_update_font_features (fontchooser))
         has_tweak = TRUE;
       if (gtk_font_chooser_widget_update_font_variations (fontchooser))