[gtk+] label: Only get font metrics if we have to

[Benjamin Otte <otte src gnome org>]

commit 0930de944697b76008863f87d2adce7f059e5a4a
Author: Benjamin Otte <otte redhat com>
Date:   Tue Mar 29 03:31:09 2011 +0200

    label: Only get font metrics if we have to
    
    Getting these metrics is expensive, so avoid it if possible.

 gtk/gtklabel.c |   21 ++++++++++++---------
 1 files changed, 12 insertions(+), 9 deletions(-)
---
diff --git a/gtk/gtklabel.c b/gtk/gtklabel.c
index d17f4d7..e0c6c5b 100644
--- a/gtk/gtklabel.c
+++ b/gtk/gtklabel.c
@@ -3091,20 +3091,12 @@ get_label_width (GtkLabel    *label,
 {
   GtkLabelPrivate     *priv;
   PangoLayout      *layout;
-  PangoContext     *context;
-  PangoFontMetrics *metrics;
   PangoRectangle    rect;
-  gint              char_width, digit_width, char_pixels, text_width, ellipsize_chars, guess_width;
+  gint              text_width, ellipsize_chars, guess_width;
 
   priv     = label->priv;
 
   layout  = gtk_label_get_measuring_layout (label, NULL, -1);
-  context = pango_layout_get_context (layout);
-  metrics = get_font_metrics (context, GTK_WIDGET (label));
-  char_width = pango_font_metrics_get_approximate_char_width (metrics);
-  digit_width = pango_font_metrics_get_approximate_digit_width (metrics);
-  char_pixels = MAX (char_width, digit_width);
-  pango_font_metrics_unref (metrics);
       
   /* Fetch the length of the complete unwrapped text */
   pango_layout_get_extents (layout, NULL, &rect);
@@ -3141,6 +3133,17 @@ get_label_width (GtkLabel    *label,
 
   if (priv->ellipsize || priv->wrap)
     {
+      PangoContext     *context;
+      PangoFontMetrics *metrics;
+      gint              char_width, digit_width, char_pixels;
+
+      context = pango_layout_get_context (layout);
+      metrics = get_font_metrics (context, GTK_WIDGET (label));
+      char_width = pango_font_metrics_get_approximate_char_width (metrics);
+      digit_width = pango_font_metrics_get_approximate_digit_width (metrics);
+      char_pixels = MAX (char_width, digit_width);
+      pango_font_metrics_unref (metrics);
+
       *minimum = char_pixels * MAX (priv->width_chars, ellipsize_chars);
 
       /* Default to the minimum width regularly guessed by GTK+ if no minimum