[jroeloffzen] 48571: [user32] - Don't update visible regions of hidden windows. Fixes bug 5303

Author: jroeloffzen
Date: Thu Aug 19 23:36:22 2010
New Revision: 48571

URL: http://svn.reactos.org/svn/reactos?rev=48571&view=rev
Log:
[user32]
- Don't update visible regions of hidden windows.
Fixes bug 5303

Modified:
    branches/arwinss/reactos/dll/win32/user32/painting.c

Modified: branches/arwinss/reactos/dll/win32/user32/painting.c
URL:
http://svn.reactos.org/svn/reactos/branches/arwinss/reactos/dll/win32/user3…
==============================================================================
--- branches/arwinss/reactos/dll/win32/user32/painting.c [iso-8859-1] (original)
+++ branches/arwinss/reactos/dll/win32/user32/painting.c [iso-8859-1] Thu Aug 19 23:36:22
2010
@@ -911,10 +911,13 @@
     const DWORD user_flags = clip_flags | DCX_NORESETATTRS; /* flags that can be set by
user */
     struct dce *dce;
     BOOL bUpdateVisRgn = TRUE;
+    BOOL bWndVisible;
     HWND parent;
+    HWND desktop = GetDesktopWindow();
     LONG window_style = GetWindowLongW( hwnd, GWL_STYLE );
-
-    if (!hwnd) hwnd = GetDesktopWindow();
+    LONG parent_style;
+
+    if (!hwnd) hwnd = desktop;
     else hwnd = WIN_GetFullHandle( hwnd );
 
     TRACE("hwnd %p, hrgnClip %p, flags %08x\n", hwnd, hrgnClip, flags);
@@ -942,17 +945,18 @@
 
     if (flags & DCX_WINDOW) flags &= ~DCX_CLIPCHILDREN;
 
-    parent = GetAncestor( hwnd, GA_PARENT );
-    if (!parent || (parent == GetDesktopWindow()))
+    if ( !(parent = GetAncestor( hwnd, GA_PARENT)) ) parent = desktop;
+    if (parent == desktop)
         flags = (flags & ~DCX_PARENTCLIP) | DCX_CLIPSIBLINGS;
+    parent_style = GetWindowLongW( parent, GWL_STYLE );
+    bWndVisible = (window_style & WS_VISIBLE) && (parent_style &
WS_VISIBLE);
 
     /* it seems parent clip is ignored when clipping siblings or children */
     if (flags & (DCX_CLIPSIBLINGS | DCX_CLIPCHILDREN)) flags &= ~DCX_PARENTCLIP;
 
     if( flags & DCX_PARENTCLIP )
     {
-        LONG parent_style = GetWindowLongW( parent, GWL_STYLE );
-        if( (window_style & WS_VISIBLE) && (parent_style & WS_VISIBLE) )
+        if (bWndVisible)
         {
             flags &= ~DCX_CLIPCHILDREN;
             if (parent_style & WS_CLIPSIBLINGS) flags |= DCX_CLIPSIBLINGS;
@@ -1036,7 +1040,7 @@
 
     if (SetHookFlags( dce->hdc, DCHF_VALIDATEVISRGN )) bUpdateVisRgn = TRUE;  /* DC
was dirty */
 
-    if (bUpdateVisRgn) update_visible_region( dce );
+    if (bWndVisible && bUpdateVisRgn) update_visible_region( dce );
 
     TRACE("(%p,%p,0x%x): returning %p\n", hwnd, hrgnClip, flags, dce->hdc);
     return dce->hdc;