[evince] libview: do not redraw the whole view when caret cursor moves

[Carlos Garcia Campos <carlosgc src gnome org>]

commit e39ac992f03fe66c3010ee474b846616ba73ea9f
Author: Carlos Garcia Campos <carlosgc gnome org>
Date:   Thu Jul 18 14:13:38 2013 +0200

    libview: do not redraw the whole view when caret cursor moves
    
    Invalidate the previous and new regions instead.

 libview/ev-view.c |   49 +++++++++++++++++++++++++++++++++----------------
 1 files changed, 33 insertions(+), 16 deletions(-)
---
diff --git a/libview/ev-view.c b/libview/ev-view.c
index 70c2cbb..970e0d3 100644
--- a/libview/ev-view.c
+++ b/libview/ev-view.c
@@ -4320,9 +4320,14 @@ position_caret_cursor_at_location (EvView *view,
 
 static gboolean
 position_caret_cursor_for_event (EvView         *view,
-                                GdkEventButton *event)
+                                GdkEventButton *event,
+                                gboolean        redraw)
 {
        GdkRectangle area;
+       GdkRectangle prev_area = { 0, 0, 0, 0 };
+
+       if (redraw)
+               get_caret_cursor_area (view, view->cursor_page, view->cursor_offset, &prev_area);
 
        if (!position_caret_cursor_at_location (view, event->x, event->y))
                return FALSE;
@@ -4334,6 +4339,16 @@ position_caret_cursor_for_event (EvView         *view,
 
        g_signal_emit (view, signals[SIGNAL_CURSOR_MOVED], 0, view->cursor_page, view->cursor_offset);
 
+       if (redraw) {
+               cairo_region_t *damage_region;
+
+               damage_region = cairo_region_create_rectangle (&prev_area);
+               cairo_region_union_rectangle (damage_region, &area);
+               gdk_window_invalidate_region (gtk_widget_get_window (GTK_WIDGET (view)),
+                                             damage_region, TRUE);
+               cairo_region_destroy (damage_region);
+       }
+
        return TRUE;
 }
 
@@ -4385,7 +4400,7 @@ ev_view_button_press_event (GtkWidget      *widget,
                                        view->selection_info.in_drag = TRUE;
                                } else {
                                        start_selection_for_event (view, event);
-                                       if (position_caret_cursor_for_event (view, event)) {
+                                       if (position_caret_cursor_for_event (view, event, TRUE)) {
                                                view->cursor_blink_time = 0;
                                                ev_view_pend_cursor_blink (view);
                                        }
@@ -4419,11 +4434,9 @@ ev_view_button_press_event (GtkWidget      *widget,
                                if (EV_IS_SELECTION (view->document))
                                        start_selection_for_event (view, event);
 
-                               if (position_caret_cursor_for_event (view, event)) {
+                               if (position_caret_cursor_for_event (view, event, TRUE)) {
                                        view->cursor_blink_time = 0;
                                        ev_view_pend_cursor_blink (view);
-
-                                       gtk_widget_queue_draw (widget);
                                }
                        }
                }                       
@@ -4870,7 +4883,7 @@ ev_view_button_release_event (GtkWidget      *widget,
                clear_link_selected (view);
                ev_view_update_primary_selection (view);
 
-               position_caret_cursor_for_event (view, event);
+               position_caret_cursor_for_event (view, event, FALSE);
 
                if (view->selection_info.in_drag)
                        clear_selection (view);
@@ -5275,10 +5288,12 @@ ev_view_move_cursor (EvView         *view,
                     gint            count,
                     gboolean        extend_selection)
 {
-       GdkRectangle rect;
-       gint         prev_offset;
-       gint         prev_page;
-       gboolean     clear_selections = FALSE;
+       GdkRectangle    rect;
+       GdkRectangle    prev_rect;
+       gint            prev_offset;
+       gint            prev_page;
+       cairo_region_t *damage_region;
+       gboolean        clear_selections = FALSE;
 
        if (!view->caret_enabled || view->rotation != 0)
                return FALSE;
@@ -5363,6 +5378,10 @@ ev_view_move_cursor (EvView         *view,
                view->cursor_line_offset = rect.x;
        }
 
+       damage_region = cairo_region_create_rectangle (&rect);
+       if (get_caret_cursor_area (view, prev_page, prev_offset, &prev_rect))
+               cairo_region_union_rectangle (damage_region, &prev_rect);
+
        rect.x += view->scroll_x;
        rect.y += view->scroll_y;
 
@@ -5371,14 +5390,14 @@ ev_view_move_cursor (EvView         *view,
 
        g_signal_emit (view, signals[SIGNAL_CURSOR_MOVED], 0, view->cursor_page, view->cursor_offset);
 
+       gdk_window_invalidate_region (gtk_widget_get_window (GTK_WIDGET (view)),
+                                     damage_region, TRUE);
+       cairo_region_destroy (damage_region);
+
        /* Select text */
        if (extend_selection && EV_IS_SELECTION (view->document)) {
-               GdkRectangle prev_rect;
                GdkPoint start_point, end_point;
 
-               if (!get_caret_cursor_area (view, prev_page, prev_offset, &prev_rect))
-                       return TRUE;
-
                start_point.x = prev_rect.x + view->scroll_x;
                start_point.y = prev_rect.y + (prev_rect.height / 2) + view->scroll_y;
 
@@ -5389,8 +5408,6 @@ ev_view_move_cursor (EvView         *view,
        } else if (clear_selections)
                clear_selection (view);
 
-       gtk_widget_queue_draw (GTK_WIDGET (view));
-
        return TRUE;
 }