+ g_assert (new_sel || old_sel);
+
+ /* is the page we're looking at on the screen?*/
+ cur_page = new_sel ? new_sel->page : old_sel->page;
+ if (cur_page < view->start_page || cur_page > view->end_page)
+ continue;
+
+ /* seed the cache with a new page. We are going to need the new
+ * region too. */
+ if (new_sel) {
+ GdkRegion *tmp_region = NULL;
+ ev_pixbuf_cache_get_selection_pixbuf (view->pixbuf_cache,
+ cur_page,
+ view->scale,
+ &tmp_region);
+ if (tmp_region) {
+ new_sel->covered_region = gdk_region_copy (tmp_region);
+ }
+ }
+
+ /* Now we figure out what needs redrawing */
+ if (old_sel && new_sel) {
+ if (old_sel->covered_region &&
+ new_sel->covered_region) {
+ /* We only want to redraw the areas that have
+ * changed, so we xor the old and new regions
+ * and redraw if it's different */
+ region = gdk_region_copy (old_sel->covered_region);
+ gdk_region_xor (region, new_sel->covered_region);
+ if (gdk_region_empty (region)) {
+ gdk_region_destroy (region);
+ region = NULL;
+ }
+ } else if (old_sel->covered_region) {
+ region = gdk_region_copy (old_sel->covered_region);
+ } else if (new_sel->covered_region) {
+ region = gdk_region_copy (new_sel->covered_region);
+ }
+ } else if (old_sel && !new_sel) {
+ if (old_sel->covered_region && !gdk_region_empty (old_sel->covered_region)) {
+ region = gdk_region_copy (old_sel->covered_region);
+ }
+ } else if (!old_sel && new_sel) {
+ if (new_sel->covered_region && !gdk_region_empty (new_sel->covered_region)) {
+ region = gdk_region_copy (new_sel->covered_region);
+ }
+ } else {
+ g_assert_not_reached ();
+ }
+
+ /* Redraw the damaged region! */
+ if (region) {
+ GdkRectangle page_area;
+ GtkBorder border;
+
+ get_page_extents (view, cur_page, &page_area, &border);
+ gdk_region_offset (region,
+ page_area.x + border.left - view->scroll_x,
+ page_area.y + border.top - view->scroll_y);
+ gdk_window_invalidate_region (GTK_WIDGET (view)->window, region, TRUE);
+ gdk_region_destroy (region);
+ }
+ }
+
+ /* Free the old list, now that we're done with it. */
+ g_list_foreach (old_list, (GFunc) selection_free, NULL);