textview: use pixelcache to indirectly renderer to widget.

This patch uses GtkPixelCache to render the contents of the widget,
and typically a bit more, to an offscreen surface. The pixel cache in
turn manages rendering to the actual surface for the widget.

The current strategy for the size to render is the size of the widget
plus half the height.

https://bugzilla.gnome.org/show_bug.cgi?id=701125

diff --git a/gtk/gtktextview.c b/gtk/gtktextview.c
index 889aab297f47b0137b2a10c9ff5d095ceb929f84..8a96a5642775ff9a36f70a35c927dabf37cbaa28 100644 (file)
--- a/gtk/gtktextview.c
+++ b/gtk/gtktextview.c
@@ -53,6 +53,7 @@
 #include "gtkcssstylepropertyprivate.h"
 #include "gtkbubblewindowprivate.h"
 #include "gtktoolbar.h"
+#include "gtkpixelcacheprivate.h"
 
 #include "a11y/gtktextviewaccessibleprivate.h"
 
@@ -200,6 +201,8 @@ struct _GtkTextViewPrivate
 
   GtkTextPendingScroll *pending_scroll;
 
+  GtkPixelCache *pixel_cache;
+
   /* Default style settings */
   gint pixels_above_lines;
   gint pixels_below_lines;
@@ -238,6 +241,8 @@ struct _GtkTextViewPrivate
   guint cursor_handle_dragged : 1;
   guint selection_handle_dragged : 1;
   guint populate_all   : 1;
+
+  gboolean in_scroll : 1;
 };
 
 struct _GtkTextPendingScroll
@@ -524,6 +529,9 @@ static void gtk_text_view_update_handles       (GtkTextView           *text_view
 static void gtk_text_view_selection_bubble_popup_unset (GtkTextView *text_view);
 static void gtk_text_view_selection_bubble_popup_set   (GtkTextView *text_view);
 
+static void gtk_text_view_queue_draw_region (GtkWidget            *widget,
+                                             const cairo_region_t *region);
+
 
 /* FIXME probably need the focus methods. */
 
@@ -661,7 +669,9 @@ gtk_text_view_class_init (GtkTextViewClass *klass)
   widget_class->drag_data_received = gtk_text_view_drag_data_received;
 
   widget_class->popup_menu = gtk_text_view_popup_menu;
-  
+
+  widget_class->queue_draw_region = gtk_text_view_queue_draw_region;
+
   container_class->add = gtk_text_view_add;
   container_class->remove = gtk_text_view_remove;
   container_class->forall = gtk_text_view_forall;
@@ -1459,6 +1469,9 @@ gtk_text_view_init (GtkTextView *text_view)
 
   gtk_widget_set_can_focus (widget, TRUE);
 
+  priv->pixel_cache = _gtk_pixel_cache_new ();
+  _gtk_pixel_cache_set_content (priv->pixel_cache, CAIRO_CONTENT_COLOR_ALPHA);
+
   /* Set up default style */
   priv->wrap_mode = GTK_WRAP_NONE;
   priv->pixels_above_lines = 0;
@@ -3133,6 +3146,12 @@ gtk_text_view_destroy (GtkWidget *widget)
       priv->im_spot_idle = 0;
     }
 
+  if (priv->pixel_cache)
+    {
+      _gtk_pixel_cache_free (priv->pixel_cache);
+      priv->pixel_cache = NULL;
+    }
+
   GTK_WIDGET_CLASS (gtk_text_view_parent_class)->destroy (widget);
 }
 
@@ -3682,6 +3701,9 @@ gtk_text_view_size_allocate (GtkWidget *widget,
 
   DV(g_print(G_STRLOC"\n"));
 
+  _gtk_pixel_cache_set_extra_size (priv->pixel_cache, 0,
+                                   allocation->height / 2);
+
   gtk_widget_get_allocation (widget, &widget_allocation);
   size_changed =
     widget_allocation.width != allocation->width ||
@@ -5214,10 +5236,20 @@ gtk_text_view_paint (GtkWidget      *widget,
   cairo_restore (cr);
 }
 
+static void
+draw_text (cairo_t  *cr,
+           gpointer  user_data)
+{
+  GtkWidget *widget = user_data;
+
+  gtk_text_view_paint (widget, cr);
+}
+
 static gboolean
 gtk_text_view_draw (GtkWidget *widget,
                     cairo_t   *cr)
 {
+  GtkTextViewPrivate *priv = ((GtkTextView *)widget)->priv;
   GSList *tmp_list;
   GdkWindow *window;
   GtkStyleContext *context;
@@ -5241,10 +5273,29 @@ gtk_text_view_draw (GtkWidget *widget,
                                      GTK_TEXT_WINDOW_TEXT);
   if (gtk_cairo_should_draw_window (cr, window))
     {
+      cairo_rectangle_int_t view_rect;
+      cairo_rectangle_int_t canvas_rect;
+      GtkAllocation alloc;
+
       DV(g_print (">Exposed ("G_STRLOC")\n"));
+
+      gtk_widget_get_allocation (widget, &alloc);
+
+      view_rect.x = 0;
+      view_rect.y = 0;
+      view_rect.width = gdk_window_get_width (window);
+      view_rect.height = gdk_window_get_height (window);
+
+      canvas_rect.x = -gtk_adjustment_get_value (priv->hadjustment);
+      canvas_rect.y = -gtk_adjustment_get_value (priv->vadjustment);
+      canvas_rect.width = priv->cached_size_request.width;
+      canvas_rect.height = priv->cached_size_request.height;
+
       cairo_save (cr);
       gtk_cairo_transform_to_window (cr, widget, window);
-      gtk_text_view_paint (widget, cr);
+      _gtk_pixel_cache_draw (priv->pixel_cache, cr, window,
+                             &view_rect, &canvas_rect,
+                             draw_text, widget);
       cairo_restore (cr);
     }
 
@@ -8911,6 +8962,45 @@ text_window_free (GtkTextWindow *win)
   g_free (win);
 }
 
+static void
+gtk_text_view_queue_draw_region (GtkWidget            *widget,
+                                 const cairo_region_t *region)
+{
+  GtkTextView *text_view = GTK_TEXT_VIEW (widget);
+
+  /* There is no way we can know if a region targets the
+     not-currently-visible but in pixel cache region, so we
+     always just invalidate the whole thing whenever the
+     text view gets a queue draw. This doesn't normally happen
+     in normal scrolling cases anyway. */
+  _gtk_pixel_cache_invalidate (text_view->priv->pixel_cache, NULL);
+
+  GTK_WIDGET_CLASS (gtk_text_view_parent_class)->queue_draw_region (widget,
+                                                                    region);
+}
+
+static void
+text_window_invalidate_handler (GdkWindow      *window,
+                                cairo_region_t *region)
+{
+  gpointer widget;
+  GtkTextView *text_view;
+  int y;
+
+  gdk_window_get_user_data (window, &widget);
+  text_view = GTK_TEXT_VIEW (widget);
+
+  /* Scrolling will invalidate everything in the bin window,
+   * but we already have it in the cache, so we can ignore that */
+  if (text_view->priv->in_scroll)
+    return;
+
+  y = gtk_adjustment_get_value (text_view->priv->vadjustment);
+  cairo_region_translate (region, 0, y);
+  _gtk_pixel_cache_invalidate (text_view->priv->pixel_cache, region);
+  cairo_region_translate (region, 0, -y);
+}
+
 static void
 text_window_realize (GtkTextWindow *win,
                      GtkWidget     *widget)
@@ -8939,6 +9029,9 @@ text_window_realize (GtkTextWindow *win,
   win->window = gdk_window_new (window,
                                 &attributes, attributes_mask);
 
+  gdk_window_set_invalidate_handler (win->window,
+                                     text_window_invalidate_handler);
+
   gdk_window_show (win->window);
   gtk_widget_register_window (win->widget, win->window);
   gdk_window_lower (win->window);
@@ -9050,7 +9143,9 @@ text_window_scroll        (GtkTextWindow *win,
     {
       if (priv->selection_bubble)
         _gtk_bubble_window_popdown (GTK_BUBBLE_WINDOW (priv->selection_bubble));
+      view->priv->in_scroll = TRUE;
       gdk_window_scroll (win->bin_window, dx, dy);
+      view->priv->in_scroll = FALSE;
     }
 }