From 964d21ea51d59e02cbdc0171a67d4c56f4f44130 Mon Sep 17 00:00:00 2001
From: Karl Tomlinson <karlt+@karlt.net>
Date: Mon, 27 Jul 2009 13:28:05 +1200
Subject: [PATCH] b=478519 don't pass gdk invalidation regions when the drawing
 area is not visible. r=roc

--HG--
extra : rebase_source : e13e39054de48e6523c5eeb7bca71aca20a4df37
---
 widget/src/gtk2/nsWindow.cpp | 57 ++++++++++++++++++++++++------------
 widget/src/gtk2/nsWindow.h   |  1 +
 2 files changed, 39 insertions(+), 19 deletions(-)

diff --git a/widget/src/gtk2/nsWindow.cpp b/widget/src/gtk2/nsWindow.cpp
index 6bf2125506b..15f3f310b50 100644
--- a/widget/src/gtk2/nsWindow.cpp
+++ b/widget/src/gtk2/nsWindow.cpp
@@ -938,16 +938,41 @@ nsWindow::SetModal(PRBool aModal)
     return NS_OK;
 }
 
+// nsIWidget method, which means IsShown.
 NS_IMETHODIMP
-nsWindow::IsVisible(PRBool & aState)
+nsWindow::IsVisible(PRBool& aState)
 {
-    aState = mIsVisible;
-    if (mIsTopLevel && mShell) {
-        aState = GTK_WIDGET_VISIBLE(mShell);
-    }
+    aState = mIsShown;
     return NS_OK;
 }
 
+// Internal method, which returns false when no part of the window can be seen.
+PRBool
+nsWindow::CanBeSeen()
+{
+    // mIsVisible keeps track of whether any part of the window is unobscured,
+    // but does not get updated when the window changes state from viewable to
+    // not viewable (when any ancestor window is unmapped) because
+    // VisibilityNotifty events do not get sent on such a change in state.
+    if (!mIsShown || !mIsVisible)
+        return PR_FALSE;
+
+    GtkWidget *topWidget = nsnull;
+    GetToplevelWidget(&topWidget);
+
+    // If the toplevel widget has been unmapped, then record this in
+    // mIsVisible.  mIsVisible will be updated in OnVisibilityNotifyEvent()
+    // when its window becomes viewable again.
+    // (gdk_window_is_viewable() is not suitable here as it does not
+    // check GDK_WINDOW_STATE_ICONIFIED.)
+    mIsVisible =
+        topWidget &&
+        !(gdk_window_get_state(topWidget->window) &
+          (GDK_WINDOW_STATE_ICONIFIED|GDK_WINDOW_STATE_WITHDRAWN));
+        
+    return mIsVisible;
+}
+
 NS_IMETHODIMP
 nsWindow::ConstrainPosition(PRBool aAllowSlop, PRInt32 *aX, PRInt32 *aY)
 {
@@ -1670,8 +1695,10 @@ nsWindow::Validate()
 NS_IMETHODIMP
 nsWindow::Invalidate(PRBool aIsSynchronous)
 {
-    GdkRectangle rect;
+    if (!mDrawingarea || !CanBeSeen())
+        return NS_OK;
 
+    GdkRectangle rect;
     rect.x = mBounds.x;
     rect.y = mBounds.y;
     rect.width = mBounds.width;
@@ -1680,9 +1707,6 @@ nsWindow::Invalidate(PRBool aIsSynchronous)
     LOGDRAW(("Invalidate (all) [%p]: %d %d %d %d\n", (void *)this,
              rect.x, rect.y, rect.width, rect.height));
 
-    if (!mDrawingarea)
-        return NS_OK;
-
     gdk_window_invalidate_rect(mDrawingarea->inner_window,
                                &rect, FALSE);
     if (aIsSynchronous)
@@ -1695,8 +1719,10 @@ NS_IMETHODIMP
 nsWindow::Invalidate(const nsIntRect &aRect,
                      PRBool           aIsSynchronous)
 {
-    GdkRectangle rect;
+    if (!mDrawingarea || !CanBeSeen())
+        return NS_OK;
 
+    GdkRectangle rect;
     rect.x = aRect.x;
     rect.y = aRect.y;
     rect.width = aRect.width;
@@ -1705,9 +1731,6 @@ nsWindow::Invalidate(const nsIntRect &aRect,
     LOGDRAW(("Invalidate (rect) [%p]: %d %d %d %d (sync: %d)\n", (void *)this,
              rect.x, rect.y, rect.width, rect.height, aIsSynchronous));
 
-    if (!mDrawingarea)
-        return NS_OK;
-
     gdk_window_invalidate_rect(mDrawingarea->inner_window,
                                &rect, FALSE);
     if (aIsSynchronous)
@@ -4643,9 +4666,7 @@ nsWindow::GrabPointer(void)
     // If the window isn't visible, just set the flag to retry the
     // grab.  When this window becomes visible, the grab will be
     // retried.
-    PRBool visibility = PR_TRUE;
-    IsVisible(visibility);
-    if (!visibility) {
+    if (!CanBeSeen()) {
         LOG(("GrabPointer: window not visible\n"));
         mRetryPointerGrab = PR_TRUE;
         return;
@@ -4682,9 +4703,7 @@ nsWindow::GrabKeyboard(void)
     // If the window isn't visible, just set the flag to retry the
     // grab.  When this window becomes visible, the grab will be
     // retried.
-    PRBool visibility = PR_TRUE;
-    IsVisible(visibility);
-    if (!visibility) {
+    if (!CanBeSeen()) {
         LOG(("GrabKeyboard: window not visible\n"));
         mRetryKeyboardGrab = PR_TRUE;
         return;
diff --git a/widget/src/gtk2/nsWindow.h b/widget/src/gtk2/nsWindow.h
index ed5024e312d..82ac881db22 100644
--- a/widget/src/gtk2/nsWindow.h
+++ b/widget/src/gtk2/nsWindow.h
@@ -453,6 +453,7 @@ protected:
     PRPackedBool        mPlaced;
 
 private:
+    PRBool             CanBeSeen();
     void               GetToplevelWidget(GtkWidget **aWidget);
     GtkWidget         *GetMozContainerWidget();
     nsWindow          *GetContainerWindow();