Bug 471568 – Optimizations in _pango_cairo_update_context()

2007-10-24  Behdad Esfahbod  <behdad@gnome.org>

        Bug 471568 – Optimizations in _pango_cairo_update_context()

        * pango/pangocairo-context.c (_pango_cairo_update_context):
        Skip change notification about matrix changes if merged font
        options for the context set metrics hinting to off.


svn path=/trunk/; revision=2471

2 files changed, 34 insertions, 19 deletions

diff --git a/ChangeLog b/ChangeLog
index c77764cf..eee618cb 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,13 @@
 2007-10-24  Behdad Esfahbod  <behdad@gnome.org>
 
+	Bug 471568 – Optimizations in _pango_cairo_update_context()
+
+	* pango/pangocairo-context.c (_pango_cairo_update_context):
+	Skip change notification about matrix changes if merged font
+	options for the context set metrics hinting to off.
+
+2007-10-24  Behdad Esfahbod  <behdad@gnome.org>
+
 	Bug 489909 – pango_cairo_update_context() should ignore matrix
 	translation
 
diff --git a/pango/pangocairo-context.c b/pango/pangocairo-context.c
index 53cabfc6..1948ebc9 100644
--- a/pango/pangocairo-context.c
+++ b/pango/pangocairo-context.c
@@ -90,29 +90,12 @@ _pango_cairo_update_context (cairo_t      *cr,
   cairo_matrix_t cairo_matrix;
   cairo_surface_t *target;
   PangoMatrix pango_matrix;
-  const PangoMatrix *layout_matrix, identity_matrix = PANGO_MATRIX_INIT;
+  const PangoMatrix *current_matrix, identity_matrix = PANGO_MATRIX_INIT;
+  const cairo_font_options_t *merged_options;
   gboolean changed = FALSE;
 
   info = get_context_info (context, TRUE);
 
-  cairo_get_matrix (cr, &cairo_matrix);
-  pango_matrix.xx = cairo_matrix.xx;
-  pango_matrix.yx = cairo_matrix.yx;
-  pango_matrix.xy = cairo_matrix.xy;
-  pango_matrix.yy = cairo_matrix.yy;
-  pango_matrix.x0 = cairo_matrix.x0;
-  pango_matrix.y0 = cairo_matrix.y0;
-
-  layout_matrix = pango_context_get_matrix (context);
-  if (!layout_matrix)
-    layout_matrix = &identity_matrix;
-
-  /* ignore translation offsets */
-  if (0 != memcmp (&pango_matrix, layout_matrix, 4 * sizeof (double)))
-    changed = TRUE;
-
-  pango_context_set_matrix (context, &pango_matrix);
-
 
   target = cairo_get_target (cr);
 
@@ -137,6 +120,30 @@ _pango_cairo_update_context (cairo_t      *cr,
       info->merged_options = NULL;
     }
 
+  merged_options = _pango_cairo_context_get_merged_font_options (context);
+
+
+  cairo_get_matrix (cr, &cairo_matrix);
+  pango_matrix.xx = cairo_matrix.xx;
+  pango_matrix.yx = cairo_matrix.yx;
+  pango_matrix.xy = cairo_matrix.xy;
+  pango_matrix.yy = cairo_matrix.yy;
+  pango_matrix.x0 = cairo_matrix.x0;
+  pango_matrix.y0 = cairo_matrix.y0;
+
+  current_matrix = pango_context_get_matrix (context);
+  if (!current_matrix)
+    current_matrix = &identity_matrix;
+
+  /* layout is matrix-independent if metrics-hinting is off.
+   * also ignore matrix translation offsets */
+  if ((cairo_font_options_get_hint_metrics (merged_options) != CAIRO_HINT_METRICS_OFF) &&
+      (0 != memcmp (&pango_matrix, current_matrix, 4 * sizeof (double))))
+    changed = TRUE;
+
+  pango_context_set_matrix (context, &pango_matrix);
+
+
   return changed;
 }