[gtk+] css: Implement font-variant-position

[Matthias Clasen <matthiasc src gnome org>]

commit 01ed84fbefcb2cec8518daef73d7621249ab05a8
Author: Matthias Clasen <mclasen redhat com>
Date:   Mon Sep 18 00:01:39 2017 -0400

    css: Implement font-variant-position
    
    This gets translated to the corresponding OpenType features.

 gtk/gtkcssstyle.c             |   14 ++++++++++++++
 gtk/gtkcssstylepropertyimpl.c |   22 +++++++++++++++++++++-
 gtk/gtkcsstypesprivate.h      |    1 +
 3 files changed, 36 insertions(+), 1 deletions(-)
---
diff --git a/gtk/gtkcssstyle.c b/gtk/gtkcssstyle.c
index 44a9f1c..a0bdc8d 100644
--- a/gtk/gtkcssstyle.c
+++ b/gtk/gtkcssstyle.c
@@ -227,6 +227,7 @@ gtk_css_style_get_pango_attributes (GtkCssStyle *style)
   gint letter_spacing;
   GtkCssValue *kerning;
   GtkCssValue *ligatures;
+  GtkCssValue *position;
   GString *s;
   int i;
 
@@ -265,6 +266,7 @@ gtk_css_style_get_pango_attributes (GtkCssStyle *style)
     }
 
   /* OpenType features */
+
   s = g_string_new ("");
 
   kerning = gtk_css_style_get_value (style, GTK_CSS_PROPERTY_FONT_KERNING);
@@ -298,6 +300,18 @@ gtk_css_style_get_pango_attributes (GtkCssStyle *style)
         g_string_append (s, "calt 0");
     }
 
+  position = gtk_css_style_get_value (style, GTK_CSS_PROPERTY_FONT_VARIANT_POSITION);
+  if (strcmp (_gtk_css_ident_value_get (position), "sub") == 0)
+    {
+      if (s->len > 0) g_string_append (s, ", ");
+      g_string_append (s, "subs 1");
+    }
+  else if (strcmp (_gtk_css_ident_value_get (kerning), "super") == 0)
+    {
+      if (s->len > 0) g_string_append (s, ", ");
+      g_string_append (s, "sups 1");
+    }
+
   attrs = add_pango_attr (attrs, pango_attr_font_features_new (s->str));
   g_string_free (s, TRUE);
 
diff --git a/gtk/gtkcssstylepropertyimpl.c b/gtk/gtkcssstylepropertyimpl.c
index a07fe1b..3514dc2 100644
--- a/gtk/gtkcssstylepropertyimpl.c
+++ b/gtk/gtkcssstylepropertyimpl.c
@@ -629,6 +629,19 @@ parse_font_variant_ligatures (GtkCssStyleProperty *property,
 }
 
 static GtkCssValue *
+parse_font_variant_position (GtkCssStyleProperty *property,
+                             GtkCssParser        *parser)
+{
+  GtkCssValue *value = NULL;
+
+  value = _gtk_css_ident_value_try (parser, "normal", "sub", "super", NULL);
+  if (value == NULL)
+    _gtk_css_parser_error (parser, "unknown value for property");
+
+  return value;
+}
+
+static GtkCssValue *
 box_shadow_value_parse (GtkCssStyleProperty *property,
                         GtkCssParser        *parser)
 {
@@ -1129,7 +1142,14 @@ _gtk_css_style_property_init_properties (void)
                                           parse_font_variant_ligatures,
                                           NULL,
                                           _gtk_css_array_value_new (_gtk_css_ident_value_new ("normal")));
-
+  gtk_css_style_property_register        ("font-variant-position",
+                                          GTK_CSS_PROPERTY_FONT_VARIANT_POSITION,
+                                          G_TYPE_NONE,
+                                          0,
+                                          GTK_CSS_AFFECTS_TEXT | GTK_CSS_AFFECTS_TEXT_ATTRS,
+                                          parse_font_variant_position,
+                                          NULL,
+                                          _gtk_css_ident_value_new ("normal"));
   gtk_css_style_property_register        ("text-shadow",
                                           GTK_CSS_PROPERTY_TEXT_SHADOW,
                                           G_TYPE_NONE,
diff --git a/gtk/gtkcsstypesprivate.h b/gtk/gtkcsstypesprivate.h
index 2ff6750..cb340ea 100644
--- a/gtk/gtkcsstypesprivate.h
+++ b/gtk/gtkcsstypesprivate.h
@@ -165,6 +165,7 @@ enum { /*< skip >*/
   GTK_CSS_PROPERTY_TEXT_DECORATION_STYLE,
   GTK_CSS_PROPERTY_FONT_KERNING,
   GTK_CSS_PROPERTY_FONT_VARIANT_LIGATURES,
+  GTK_CSS_PROPERTY_FONT_VARIANT_POSITION,
   GTK_CSS_PROPERTY_TEXT_SHADOW,
   GTK_CSS_PROPERTY_BOX_SHADOW,
   GTK_CSS_PROPERTY_MARGIN_TOP,