Added function to scroll contents of a window while keeping the window

Thu May 18 18:43:21 2000  Owen Taylor  <otaylor@redhat.com>

	* gdk/gdkwindow.h gdk/x11/gdkgeometry-x11.c (gdk_window_scroll):
	Added function to scroll contents of a window while keeping the
	window constant. Works by XCopyArea or guffaw-scrolling depending
	on the details of how the window is set up. (guffaw-scrolling
	still needs to be filled in.)

9 files changed, 213 insertions, 51 deletions

diff --git a/ChangeLog b/ChangeLog
index f07f72fa59..1f34fdd31f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+Thu May 18 18:43:21 2000  Owen Taylor  <otaylor@redhat.com>
+
+	* gdk/gdkwindow.h gdk/x11/gdkgeometry-x11.c (gdk_window_scroll): 
+	Added function to scroll contents of a window while keeping the
+	window constant. Works by XCopyArea or guffaw-scrolling depending
+	on the details of how the window is set up. (guffaw-scrolling
+	still needs to be filled in.)
+
 Wed May 17 22:36:53 2000  Owen Taylor  <otaylor@redhat.com>
 
 	* gtk/gtktextiter.c gtk/gtkmain.c: Add a debug key for the text widget,
diff --git a/ChangeLog.pre-2-0 b/ChangeLog.pre-2-0
index f07f72fa59..1f34fdd31f 100644
--- a/ChangeLog.pre-2-0
+++ b/ChangeLog.pre-2-0
@@ -1,3 +1,11 @@
+Thu May 18 18:43:21 2000  Owen Taylor  <otaylor@redhat.com>
+
+	* gdk/gdkwindow.h gdk/x11/gdkgeometry-x11.c (gdk_window_scroll): 
+	Added function to scroll contents of a window while keeping the
+	window constant. Works by XCopyArea or guffaw-scrolling depending
+	on the details of how the window is set up. (guffaw-scrolling
+	still needs to be filled in.)
+
 Wed May 17 22:36:53 2000  Owen Taylor  <otaylor@redhat.com>
 
 	* gtk/gtktextiter.c gtk/gtkmain.c: Add a debug key for the text widget,
diff --git a/ChangeLog.pre-2-10 b/ChangeLog.pre-2-10
index f07f72fa59..1f34fdd31f 100644
--- a/ChangeLog.pre-2-10
+++ b/ChangeLog.pre-2-10
@@ -1,3 +1,11 @@
+Thu May 18 18:43:21 2000  Owen Taylor  <otaylor@redhat.com>
+
+	* gdk/gdkwindow.h gdk/x11/gdkgeometry-x11.c (gdk_window_scroll): 
+	Added function to scroll contents of a window while keeping the
+	window constant. Works by XCopyArea or guffaw-scrolling depending
+	on the details of how the window is set up. (guffaw-scrolling
+	still needs to be filled in.)
+
 Wed May 17 22:36:53 2000  Owen Taylor  <otaylor@redhat.com>
 
 	* gtk/gtktextiter.c gtk/gtkmain.c: Add a debug key for the text widget,
diff --git a/ChangeLog.pre-2-2 b/ChangeLog.pre-2-2
index f07f72fa59..1f34fdd31f 100644
--- a/ChangeLog.pre-2-2
+++ b/ChangeLog.pre-2-2
@@ -1,3 +1,11 @@
+Thu May 18 18:43:21 2000  Owen Taylor  <otaylor@redhat.com>
+
+	* gdk/gdkwindow.h gdk/x11/gdkgeometry-x11.c (gdk_window_scroll): 
+	Added function to scroll contents of a window while keeping the
+	window constant. Works by XCopyArea or guffaw-scrolling depending
+	on the details of how the window is set up. (guffaw-scrolling
+	still needs to be filled in.)
+
 Wed May 17 22:36:53 2000  Owen Taylor  <otaylor@redhat.com>
 
 	* gtk/gtktextiter.c gtk/gtkmain.c: Add a debug key for the text widget,
diff --git a/ChangeLog.pre-2-4 b/ChangeLog.pre-2-4
index f07f72fa59..1f34fdd31f 100644
--- a/ChangeLog.pre-2-4
+++ b/ChangeLog.pre-2-4
@@ -1,3 +1,11 @@
+Thu May 18 18:43:21 2000  Owen Taylor  <otaylor@redhat.com>
+
+	* gdk/gdkwindow.h gdk/x11/gdkgeometry-x11.c (gdk_window_scroll): 
+	Added function to scroll contents of a window while keeping the
+	window constant. Works by XCopyArea or guffaw-scrolling depending
+	on the details of how the window is set up. (guffaw-scrolling
+	still needs to be filled in.)
+
 Wed May 17 22:36:53 2000  Owen Taylor  <otaylor@redhat.com>
 
 	* gtk/gtktextiter.c gtk/gtkmain.c: Add a debug key for the text widget,
diff --git a/ChangeLog.pre-2-6 b/ChangeLog.pre-2-6
index f07f72fa59..1f34fdd31f 100644
--- a/ChangeLog.pre-2-6
+++ b/ChangeLog.pre-2-6
@@ -1,3 +1,11 @@
+Thu May 18 18:43:21 2000  Owen Taylor  <otaylor@redhat.com>
+
+	* gdk/gdkwindow.h gdk/x11/gdkgeometry-x11.c (gdk_window_scroll): 
+	Added function to scroll contents of a window while keeping the
+	window constant. Works by XCopyArea or guffaw-scrolling depending
+	on the details of how the window is set up. (guffaw-scrolling
+	still needs to be filled in.)
+
 Wed May 17 22:36:53 2000  Owen Taylor  <otaylor@redhat.com>
 
 	* gtk/gtktextiter.c gtk/gtkmain.c: Add a debug key for the text widget,
diff --git a/ChangeLog.pre-2-8 b/ChangeLog.pre-2-8
index f07f72fa59..1f34fdd31f 100644
--- a/ChangeLog.pre-2-8
+++ b/ChangeLog.pre-2-8
@@ -1,3 +1,11 @@
+Thu May 18 18:43:21 2000  Owen Taylor  <otaylor@redhat.com>
+
+	* gdk/gdkwindow.h gdk/x11/gdkgeometry-x11.c (gdk_window_scroll): 
+	Added function to scroll contents of a window while keeping the
+	window constant. Works by XCopyArea or guffaw-scrolling depending
+	on the details of how the window is set up. (guffaw-scrolling
+	still needs to be filled in.)
+
 Wed May 17 22:36:53 2000  Owen Taylor  <otaylor@redhat.com>
 
 	* gtk/gtktextiter.c gtk/gtkmain.c: Add a debug key for the text widget,
diff --git a/gdk/gdkwindow.h b/gdk/gdkwindow.h
index 41087d2cc1..08e3535d15 100644
--- a/gdk/gdkwindow.h
+++ b/gdk/gdkwindow.h
@@ -120,57 +120,56 @@ struct _GdkGeometry {
 
 /* Windows
  */
-GdkWindow*    gdk_window_new	     (GdkWindow	    *parent,
-				      GdkWindowAttr *attributes,
-				      gint	     attributes_mask);
-
-void	      gdk_window_destroy     (GdkWindow	    *window);
-
-GdkWindow*    gdk_window_at_pointer  (gint	   *win_x,
-				      gint	   *win_y);
-void	      gdk_window_show	     (GdkWindow	   *window);
-void	      gdk_window_hide	     (GdkWindow	   *window);
-void	      gdk_window_withdraw    (GdkWindow	   *window);
-void	      gdk_window_move	     (GdkWindow	   *window,
-				      gint	    x,
-				      gint	    y);
-void	      gdk_window_resize	     (GdkWindow	   *window,
-				      gint	    width,
-				      gint	    height);
-void	      gdk_window_move_resize (GdkWindow	   *window,
-				      gint	    x,
-				      gint	    y,
-				      gint	    width,
-				      gint	    height);
-void	      gdk_window_reparent    (GdkWindow	   *window,
-				      GdkWindow	   *new_parent,
-				      gint	    x,
-				      gint	    y);
-void	      gdk_window_clear	     (GdkWindow	   *window);
-void	      gdk_window_clear_area  (GdkWindow	   *window,
-				      gint	    x,
-				      gint	    y,
-				      gint	    width,
-				      gint	    height);
-void	      gdk_window_clear_area_e(GdkWindow	   *window,
-				      gint	    x,
-				      gint	    y,
-				      gint	    width,
-				      gint	    height);
-void	      gdk_window_raise	     (GdkWindow	   *window);
-void	      gdk_window_lower	     (GdkWindow	   *window);
-
-void	      gdk_window_set_user_data	 (GdkWindow	  *window,
-					  gpointer	   user_data);
-void	      gdk_window_set_override_redirect(GdkWindow  *window,
-					       gboolean override_redirect);
-
-void	      gdk_window_add_filter	(GdkWindow     *window,
-					 GdkFilterFunc	function,
-					 gpointer	data);
-void	      gdk_window_remove_filter	(GdkWindow     *window,
-					 GdkFilterFunc	function,
-					 gpointer	data);
+GdkWindow* gdk_window_new                   (GdkWindow     *parent,
+					     GdkWindowAttr *attributes,
+					     gint           attributes_mask);
+void       gdk_window_destroy               (GdkWindow     *window);
+GdkWindow* gdk_window_at_pointer            (gint          *win_x,
+					     gint          *win_y);
+void       gdk_window_show                  (GdkWindow     *window);
+void       gdk_window_hide                  (GdkWindow     *window);
+void       gdk_window_withdraw              (GdkWindow     *window);
+void       gdk_window_move                  (GdkWindow     *window,
+					     gint           x,
+					     gint           y);
+void       gdk_window_resize                (GdkWindow     *window,
+					     gint           width,
+					     gint           height);
+void       gdk_window_move_resize           (GdkWindow     *window,
+					     gint           x,
+					     gint           y,
+					     gint           width,
+					     gint           height);
+void       gdk_window_scroll                (GdkWindow     *window,
+					     gint           dx,
+					     gint           dy);
+void       gdk_window_reparent              (GdkWindow     *window,
+					     GdkWindow     *new_parent,
+					     gint           x,
+					     gint           y);
+void       gdk_window_clear                 (GdkWindow     *window);
+void       gdk_window_clear_area            (GdkWindow     *window,
+					     gint           x,
+					     gint           y,
+					     gint           width,
+					     gint           height);
+void       gdk_window_clear_area_e          (GdkWindow     *window,
+					     gint           x,
+					     gint           y,
+					     gint           width,
+					     gint           height);
+void       gdk_window_raise                 (GdkWindow     *window);
+void       gdk_window_lower                 (GdkWindow     *window);
+void       gdk_window_set_user_data         (GdkWindow     *window,
+					     gpointer       user_data);
+void       gdk_window_set_override_redirect (GdkWindow     *window,
+					     gboolean       override_redirect);
+void       gdk_window_add_filter            (GdkWindow     *window,
+					     GdkFilterFunc  function,
+					     gpointer       data);
+void       gdk_window_remove_filter         (GdkWindow     *window,
+					     GdkFilterFunc  function,
+					     gpointer       data);
 
 /* 
  * This allows for making shaped (partially transparent) windows
diff --git a/gdk/x11/gdkgeometry-x11.c b/gdk/x11/gdkgeometry-x11.c
index 40855e8abb..69c0254e0e 100644
--- a/gdk/x11/gdkgeometry-x11.c
+++ b/gdk/x11/gdkgeometry-x11.c
@@ -110,6 +110,113 @@ _gdk_window_init_position (GdkWindow *window)
   gdk_window_compute_position (window, &parent_pos, &data->position_info);
 }
 
+/**
+ * gdk_window_scroll:
+ * @window: a #GdkWindow
+ * @dx: Amount to scroll in the X direction
+ * @dy: Amount to scroll in the Y direction
+ * 
+ * Scroll the contents of its window, both pixels and children, by
+ * the given amount. Portions of the window that the scroll operation
+ * brings in from offscreen areas are invalidated. The invalidated
+ * region may be bigger than what would strictly be necessary.
+ * (For X11, a minimum area will be invalidated if the window has
+ * no subwindows, or if the edges of the window's parent do not extend
+ * beyond the edges of the window. In other cases, a multi-step process
+ * is used to scroll the window which may produce temporary visual
+ * artifacts and unnecessary invalidations.)
+ **/
+void
+gdk_window_scroll (GdkWindow *window,
+		   gint       dx,
+		   gint       dy)
+{
+  GdkWindowPrivate *private = (GdkWindowPrivate *)window;
+  gboolean can_guffaw_scroll = FALSE;
+  GdkWindowXData *data;
+  
+  g_return_if_fail (window != NULL);
+  g_return_if_fail (GDK_IS_WINDOW (window));
+
+  data = (GdkWindowXData *)private->drawable.klass_data;
+
+  /* We can guffaw scroll if we are a child window, and the parent
+   * does not extend beyond our edges.
+   */
+
+  if (GDK_DRAWABLE_TYPE (private) == GDK_WINDOW_CHILD)
+    {
+      GdkWindowPrivate *parent_private = (GdkWindowPrivate *)private->parent;
+      
+      can_guffaw_scroll = (private->x <= 0 &&
+			   private->y <= 0 &&
+			   private->x + private->drawable.width >= parent_private->drawable.width &&
+			   private->y + private->drawable.height >= parent_private->drawable.height);
+    }
+
+  if (!private->children || !can_guffaw_scroll)
+    {
+      /* Use XCopyArea, then move any children later
+       */
+      GList *tmp_list;
+      GdkRegion *invalidate_region;
+      GdkRectangle dest_rect;
+
+      invalidate_region = gdk_region_rectangle (&data->position_info.clip_rect);
+      
+      dest_rect = data->position_info.clip_rect;
+      dest_rect.x += dx;
+      dest_rect.y += dy;
+      gdk_rectangle_intersect (&dest_rect, &data->position_info.clip_rect, &dest_rect);
+
+      if (dest_rect.width > 0 && dest_rect.height > 0)
+	{
+	  GC gc;
+	  XGCValues values;
+	  GdkRegion *tmp_region;
+
+	  tmp_region = gdk_region_rectangle (&dest_rect);
+	  gdk_region_subtract (invalidate_region, tmp_region);
+	  gdk_region_destroy (tmp_region);
+	  
+	  gdk_window_queue_translation (window, dx, dy);
+
+	  values.graphics_exposures = True;
+	  gc = XCreateGC (GDK_DRAWABLE_XDISPLAY (window), GDK_DRAWABLE_XID (window),
+			  GCGraphicsExposures, &values);
+
+	  XCopyArea (GDK_DRAWABLE_XDISPLAY (window),
+		     GDK_DRAWABLE_XID (window),
+		     GDK_DRAWABLE_XID (window),
+		     gc,
+		     dest_rect.x - dx, dest_rect.y - dy,
+		     dest_rect.width, dest_rect.height,
+		     dest_rect.x, dest_rect.y);
+
+	  XFreeGC (GDK_DRAWABLE_XDISPLAY (window), gc);
+	}
+
+      gdk_window_invalidate_region (window, invalidate_region, TRUE);
+      gdk_region_destroy (invalidate_region);
+
+      tmp_list = private->children;
+      while (tmp_list)
+	{
+	  private = tmp_list->data;
+	  
+	  gdk_window_move (tmp_list->data, private->x + dx, private->y + dy);
+	  
+	  tmp_list = tmp_list->next;
+	}
+    }
+  else
+    {
+      /* Guffaw scroll
+       */
+      g_warning ("gdk_window_scroll(): guffaw scrolling not yet implemented");
+    }
+}
+
 void
 _gdk_window_move_resize_child (GdkWindow *window,
 			       gint       x,