[sapwood] remove code duplication across the cropping code

[Sven Herzberg <herzi src gnome org>]

commit 667efa14d1a429a0d769d7e8ca9478e9fa8d97d2
Author: Sven Herzberg <herzi gnome-de org>
Date:   Fri Aug 13 10:29:56 2010 +0200

    remove code duplication across the cropping code
    
    * engine/sapwood-pixmap.c: remove the code duplication across the
      cropping code

 engine/sapwood-pixmap.c |  105 ++++++++++++++++++++++------------------------
 1 files changed, 50 insertions(+), 55 deletions(-)
---
diff --git a/engine/sapwood-pixmap.c b/engine/sapwood-pixmap.c
index f06c0fb..3bccb3b 100644
--- a/engine/sapwood-pixmap.c
+++ b/engine/sapwood-pixmap.c
@@ -386,46 +386,40 @@ sapwood_pixmap_render_rects_internal (SapwoodPixmap* self,
 }
 
 static void
-sapwood_crop_pixmap (cairo_surface_t* surface,
-                     cairo_surface_t* mask,
-                     int              requested_width,
-                     int              requested_height,
-                     int              original_width,
-                     int              original_height)
+sapwood_crop_single_dimension (cairo_surface_t* surface,
+                               int              x,
+                               int              y,
+                               int              width,
+                               int              height,
+                               int              displace_x,
+                               int              displace_y)
 {
   cairo_t* cr = cairo_create (surface);
-
   cairo_set_operator (cr, CAIRO_OPERATOR_SOURCE);
+  cairo_set_source_surface (cr, surface, displace_x, displace_y);
+  cairo_rectangle (cr, x, y, width, height);
+  cairo_fill (cr);
+  cairo_destroy (cr);
+}
+
+static void
+sapwood_crop_single_surface (cairo_surface_t* surface,
+                             int              requested_width,
+                             int              requested_height,
+                             int              original_width,
+                             int              original_height)
+{
+  cairo_t* cr = cairo_create (surface);
 
-  /* crop horizontally */
   if (requested_width < original_width)
     {
-      int left  = requested_width / 2;
-      int right = requested_width - left;
-
-      /* left -- remains as it is */
-
-      /* right */
-      cairo_save (cr);
-      cairo_set_source_surface (cr, surface, -(original_width - requested_width), 0);
-      cairo_rectangle (cr, left, 0, right, MAX (original_height, requested_height));
-      cairo_clip (cr);
-
-      cairo_paint (cr);
-
-      if (mask)
-        {
-          cairo_t* tmp_cr = cairo_create (mask);
-
-          /* adjust the bitmap */
-          cairo_set_source_surface (tmp_cr, cairo_get_target (tmp_cr), -(original_width - requested_width), 0);
-          cairo_set_operator (tmp_cr, CAIRO_OPERATOR_SOURCE);
-          cairo_rectangle (tmp_cr, left, 0, right, MAX (original_height, requested_height));
-          cairo_fill (tmp_cr);
+      int      left  = requested_width / 2;
+      int      right = requested_width - left;
 
-          cairo_destroy (tmp_cr);
-        }
-      cairo_restore (cr);
+      sapwood_crop_single_dimension (surface,
+                                   left, 0,
+                                   right, MAX (original_height, requested_height),
+                                   requested_width - original_width, 0);
     }
 
   if (requested_height < original_height)
@@ -433,32 +427,33 @@ sapwood_crop_pixmap (cairo_surface_t* surface,
       int top    = requested_height / 2;
       int bottom = requested_height - top;
 
-      /* top -- remains as it is */
-
-      /* bottom */
-      cairo_save (cr);
-      cairo_set_source_surface (cr, surface, 0, -(original_height - requested_height));
-      cairo_rectangle (cr, 0, top, MAX (original_width, requested_width), bottom);
-      cairo_clip (cr);
-
-      cairo_paint (cr);
+      sapwood_crop_single_dimension (surface,
+                                   0, top,
+                                   MAX (original_width, requested_width), bottom,
+                                   0, requested_height - original_height);
+    }
 
-      if (mask)
-        {
-          cairo_t* tmp_cr = cairo_create (mask);
+  cairo_destroy (cr);
+}
 
-          /* adjust the bitmap */
-          cairo_set_source_surface (tmp_cr, cairo_get_target (tmp_cr), 0, -(original_height - requested_height));
-          cairo_set_operator (tmp_cr, CAIRO_OPERATOR_SOURCE);
-          cairo_rectangle (tmp_cr, 0, top, MAX (original_width, requested_width), bottom);
-          cairo_fill (tmp_cr);
+static void /* FIXME: consider renaming to sapwood_crop_surfaces() */
+sapwood_crop_pixmap (cairo_surface_t* surface,
+                     cairo_surface_t* mask,
+                     int              requested_width,
+                     int              requested_height,
+                     int              original_width,
+                     int              original_height)
+{
+  sapwood_crop_single_surface (surface,
+                               requested_width, requested_height,
+                               original_width, original_height);
 
-          cairo_destroy (tmp_cr);
-        }
-      cairo_restore (cr);
+  if (mask)
+    {
+      sapwood_crop_single_surface (mask,
+                                   requested_width, requested_height,
+                                   original_width, original_height);
     }
-
-  cairo_destroy (cr);
 }
 
 void