[gtksourceview/wip/gutter-draw-refactoring] gutter: split on_view_draw: begin_draw()

[Sébastien Wilmet <swilmet src gnome org>]

commit d1075f87781aed898d10dddc39db82e245720232
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Sun Nov 23 13:46:03 2014 +0100

    gutter: split on_view_draw: begin_draw()

 gtksourceview/gtksourcegutter.c |  116 +++++++++++++++++++++++---------------
 1 files changed, 70 insertions(+), 46 deletions(-)
---
diff --git a/gtksourceview/gtksourcegutter.c b/gtksourceview/gtksourcegutter.c
index 22b5b08..3f6965b 100644
--- a/gtksourceview/gtksourcegutter.c
+++ b/gtksourceview/gtksourcegutter.c
@@ -960,6 +960,66 @@ apply_style (GtkSourceGutter *gutter,
        gdk_cairo_set_source_rgba (cr, &fg_color);
 }
 
+/* Call gtk_source_gutter_renderer_begin() on each renderer. */
+/* FIXME @start and @end should be of type "const GtkTextIter *", but
+ * the iter paramaters of gtk_source_gutter_renderer_begin() are not const.
+ */
+static void
+begin_draw (GtkSourceGutter *gutter,
+           GArray          *sizes,
+           GdkRectangle     background_area,
+           GtkTextIter     *start,
+           GtkTextIter     *end,
+           cairo_t         *cr)
+{
+       GdkRectangle cell_area;
+       GList *l;
+       gint idx;
+
+       cell_area = background_area;
+
+       for (l = gutter->priv->renderers, idx = 0;
+            l != NULL;
+            l = l->next, idx++)
+       {
+               Renderer *renderer = l->data;
+               gint width;
+               gint xpad;
+
+               if (!gtk_source_gutter_renderer_get_visible (renderer->renderer))
+               {
+                       continue;
+               }
+
+               width = g_array_index (sizes, gint, idx);
+
+               gtk_source_gutter_renderer_get_padding (renderer->renderer,
+                                                       &xpad,
+                                                       NULL);
+
+               background_area.width = width;
+
+               cell_area.width = width - 2 * xpad;
+               cell_area.x = background_area.x + xpad;
+
+               cairo_save (cr);
+
+               gdk_cairo_rectangle (cr, &background_area);
+               cairo_clip (cr);
+
+               gtk_source_gutter_renderer_begin (renderer->renderer,
+                                                 cr,
+                                                 &background_area,
+                                                 &cell_area,
+                                                 start,
+                                                 end);
+
+               cairo_restore (cr);
+
+               background_area.x += background_area.width;
+       }
+}
+
 static gboolean
 on_view_draw (GtkSourceView   *view,
               cairo_t         *cr,
@@ -967,11 +1027,13 @@ on_view_draw (GtkSourceView   *view,
 {
        GdkRectangle clip;
        GtkTextView *text_view;
+       GtkTextBuffer *buffer;
        GArray *sizes;
-       gint y1, y2;
-       GArray *numbers;
        GArray *pixels;
        GArray *heights;
+       GArray *numbers;
+       gint y1;
+       gint y2;
        GtkTextIter cur;
        gint cur_line;
        gint count;
@@ -979,13 +1041,11 @@ on_view_draw (GtkSourceView   *view,
        GList *item;
        GtkTextIter start;
        GtkTextIter end;
-       GtkTextBuffer *buffer;
        GdkRectangle background_area;
        GdkRectangle cell_area;
        GtkTextIter selection_start;
        GtkTextIter selection_end;
        gboolean has_selection;
-       gint idx;
        GtkStyleContext *style_context;
 
        if (!get_clip_rectangle (gutter, view, cr, &clip))
@@ -1016,13 +1076,13 @@ on_view_draw (GtkSourceView   *view,
                                               NULL,
                                               &y2);
 
-       numbers = g_array_new (FALSE, FALSE, sizeof (gint));
-       pixels = g_array_new (FALSE, FALSE, sizeof (gint));
-       heights = g_array_new (FALSE, FALSE, sizeof (gint));
        sizes = g_array_new (FALSE, FALSE, sizeof (gint));
-
        calculate_gutter_size (gutter, sizes);
 
+       pixels = g_array_new (FALSE, FALSE, sizeof (gint));
+       heights = g_array_new (FALSE, FALSE, sizeof (gint));
+       numbers = g_array_new (FALSE, FALSE, sizeof (gint));
+
        background_area.x = 0;
        background_area.height = get_lines (text_view,
                                            y1,
@@ -1050,44 +1110,7 @@ on_view_draw (GtkSourceView   *view,
        gtk_style_context_save (style_context);
        apply_style (gutter, view, style_context, cr);
 
-       for (item = gutter->priv->renderers, idx = 0;
-            item != NULL;
-            item = g_list_next (item), idx++)
-       {
-               Renderer *renderer = item->data;
-               gint xpad;
-               gint width;
-
-               width = g_array_index (sizes, gint, idx);
-
-               if (gtk_source_gutter_renderer_get_visible (renderer->renderer))
-               {
-                       gtk_source_gutter_renderer_get_padding (renderer->renderer,
-                                                               &xpad,
-                                                               NULL);
-
-                       background_area.width = width;
-
-                       cell_area.width = width - 2 * xpad;
-                       cell_area.x = background_area.x + xpad;
-
-                       cairo_save (cr);
-
-                       gdk_cairo_rectangle (cr, &background_area);
-                       cairo_clip (cr);
-
-                       gtk_source_gutter_renderer_begin (renderer->renderer,
-                                                         cr,
-                                                         &background_area,
-                                                         &cell_area,
-                                                         &start,
-                                                         &end);
-
-                       cairo_restore (cr);
-
-                       background_area.x += background_area.width;
-               }
-       }
+       begin_draw (gutter, sizes, background_area, &start, &end, cr);
 
        gtk_text_buffer_get_iter_at_mark (buffer,
                                          &cur,
@@ -1118,6 +1141,7 @@ on_view_draw (GtkSourceView   *view,
        {
                gint pos;
                gint line_to_paint;
+               gint idx;
 
                end = start;