Add a font features demo

This started life as a standalone tool, but it is nicer
to have it integrated in gtk3-demo.

1 files changed, 202 insertions, 0 deletions

diff --git a/demos/gtk-demo/font_features.c b/demos/gtk-demo/font_features.c
new file mode 100644
index 0000000000..7e8cec8138
--- /dev/null
+++ b/demos/gtk-demo/font_features.c
@@ -0,0 +1,202 @@
+/* Font Features
+ *
+ * This demonstrates support for OpenType font features with
+ * Pango attributes. The attributes can be used manually or
+ * via Pango markup.
+ */
+
+#include <gtk/gtk.h>
+
+static GtkWidget *label;
+static GtkWidget *settings;
+static GtkWidget *font;
+static GtkWidget *resetbutton;
+static GtkWidget *numcasedefault;
+static GtkWidget *numspacedefault;
+static GtkWidget *fractiondefault;
+static GtkWidget *stack;
+static GtkWidget *entry;
+
+static GtkWidget *toggle[24];
+
+static void
+update (void)
+{
+  GString *s;
+  char *font_desc;
+  char *font_settings;
+  const char *text;
+  gboolean has_feature;
+  int i;
+
+  text = gtk_entry_get_text (GTK_ENTRY (entry));
+
+  font_desc = gtk_font_chooser_get_font (GTK_FONT_CHOOSER (font));
+
+  s = g_string_new ("");
+
+  has_feature = FALSE;
+  for (i = 0; i < 24; i++)
+    {
+      if (!gtk_widget_is_sensitive (toggle[i]))
+        continue;
+
+      if (GTK_IS_RADIO_BUTTON (toggle[i]))
+        {
+          if (gtk_toggle_button_get_active (GTK_TOGGLE_BUTTON (toggle[i])))
+            {
+              if (has_feature)
+                g_string_append (s, ", ");
+              g_string_append (s, gtk_buildable_get_name (GTK_BUILDABLE (toggle[i])));
+              g_string_append (s, " 1");
+              has_feature = TRUE;
+            }
+        }
+      else
+        {
+          if (has_feature)
+            g_string_append (s, ", ");
+          g_string_append (s, gtk_buildable_get_name (GTK_BUILDABLE (toggle[i])));
+          if (gtk_toggle_button_get_active (GTK_TOGGLE_BUTTON (toggle[i])))
+            g_string_append (s, " 1");
+          else
+            g_string_append (s, " 0");
+          has_feature = TRUE;
+        }
+    }
+
+  font_settings = g_string_free (s, FALSE);
+
+  gtk_label_set_text (GTK_LABEL (settings), font_settings);
+
+  s = g_string_new ("");
+  g_string_append_printf (s, "<span font_desc='%s' font_features='%s'>%s</span>", font_desc, font_settings, text);
+
+  gtk_label_set_markup (GTK_LABEL (label), s->str);
+
+  g_string_free (s, TRUE);
+
+  g_free (font_desc);
+  g_free (font_settings);
+}
+
+static void
+reset (void)
+{
+  int i;
+
+  gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (numcasedefault), TRUE);
+  gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (numspacedefault), TRUE);
+  gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (fractiondefault), TRUE);
+  for (i = 0; i < 24; i++)
+    {
+      if (!GTK_IS_RADIO_BUTTON (toggle[i]))
+        {
+          gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (toggle[i]), FALSE);
+          gtk_widget_set_sensitive (toggle[i], FALSE);
+        }
+    }
+}
+
+static char *text;
+
+static void
+switch_to_entry (void)
+{
+  text = g_strdup (gtk_entry_get_text (GTK_ENTRY (entry)));
+  gtk_stack_set_visible_child_name (GTK_STACK (stack), "entry");
+}
+
+static void
+switch_to_label (void)
+{
+  g_free (text);
+  text = NULL;
+  gtk_stack_set_visible_child_name (GTK_STACK (stack), "label");
+  update ();
+}
+
+static gboolean
+entry_key_press (GtkEntry *entry, GdkEventKey *event)
+{
+  if (event->keyval == GDK_KEY_Escape)
+    {
+      gtk_entry_set_text (GTK_ENTRY (entry), text);
+      switch_to_label ();
+      return GDK_EVENT_STOP;
+    }
+
+  return GDK_EVENT_PROPAGATE;
+}
+
+GtkWidget *
+do_font_features (GtkWidget *do_widget)
+{
+  static GtkWidget *window = NULL;
+
+  if (!window)
+    {
+      GtkBuilder *builder;
+      int i;
+
+      builder = gtk_builder_new_from_resource ("/font-features/font-features.ui");
+
+      gtk_builder_add_callback_symbol (builder, "update", update);
+      gtk_builder_add_callback_symbol (builder, "reset", reset);
+      gtk_builder_add_callback_symbol (builder, "switch_to_entry", switch_to_entry);
+      gtk_builder_add_callback_symbol (builder, "switch_to_label", switch_to_label);
+      gtk_builder_add_callback_symbol (builder, "entry_key_press", G_CALLBACK (entry_key_press));
+      gtk_builder_connect_signals (builder, NULL);
+
+      window = GTK_WIDGET (gtk_builder_get_object (builder, "window"));
+      label = GTK_WIDGET (gtk_builder_get_object (builder, "label"));
+      settings = GTK_WIDGET (gtk_builder_get_object (builder, "settings"));
+      resetbutton = GTK_WIDGET (gtk_builder_get_object (builder, "reset"));
+      font = GTK_WIDGET (gtk_builder_get_object (builder, "font"));
+      numcasedefault = GTK_WIDGET (gtk_builder_get_object (builder, "numcasedefault"));
+      numspacedefault = GTK_WIDGET (gtk_builder_get_object (builder, "numspacedefault"));
+      fractiondefault = GTK_WIDGET (gtk_builder_get_object (builder, "fractiondefault"));
+      stack = GTK_WIDGET (gtk_builder_get_object (builder, "stack"));
+      entry = GTK_WIDGET (gtk_builder_get_object (builder, "entry"));
+
+      i = 0;
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "kern"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "liga"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "dlig"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "hlig"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "clig"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "smcp"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "c2sc"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "lnum"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "onum"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "pnum"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "tnum"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "frac"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "afrc"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "zero"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "nalt"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "swsh"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "calt"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "hist"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "salt"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "ss01"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "ss02"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "ss03"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "ss04"));
+      toggle[i++] = GTK_WIDGET (gtk_builder_get_object (builder, "ss05"));
+
+      update ();
+    }
+
+  if (!gtk_widget_get_visible (window))
+    {
+      gtk_window_present (GTK_WINDOW (window));
+    }
+  else
+    {
+      gtk_widget_destroy (window);
+      window = NULL;
+    }
+
+  return window;
+}