diff --git a/lcl/include/winapi.inc b/lcl/include/winapi.inc
index 60e688bca9..fa29ec426e 100644
--- a/lcl/include/winapi.inc
+++ b/lcl/include/winapi.inc
@@ -189,6 +189,11 @@ begin
   Result := InterfaceObject.Ellipse(DC,x1,y1,x2,y2);
 end;
 
+function ExcludeClipRect(dc: hdc; Left, Top, Right, Bottom : Integer) : Integer;
+begin
+  Result := InterfaceObject.ExcludeClipRect(DC,Left,Top,Right,Bottom);
+end;
+
 function ExtTextOut(DC: HDC; X, Y: Integer; Options: Longint; Rect: PRect; Str: PChar; Count: Longint; Dx: PInteger): Boolean;
 begin
   Result := InterfaceObject.ExtTextOut(DC, X, Y, Options, Rect, Str, Count, Dx);
@@ -365,6 +370,27 @@ begin
   Result := InterfaceObject.HideCaret(hWnd);
 end;
 
+{------------------------------------------------------------------------------
+  Function: IntersectClipRect
+  Params:  dc: hdc; Left, Top, Right, Bottom: Integer
+  Returns: Integer
+
+  Shrinks the current clipping region in the device context dc to the boundary
+  defined by Left, Top, Right, Bottom.
+
+  The result can be one of the following constants
+      Error
+      NullRegion
+      SimpleRegion
+      ComplexRegion
+      Region_Error
+
+ ------------------------------------------------------------------------------}
+function IntersectClipRect(dc: hdc; Left, Top, Right, Bottom: Integer): Integer;
+Begin
+  Result := InterfaceObject.IntersectClipRect(dc,Left,Top,Right,Bottom);
+end;
+
 Function InvalidateRect(aHandle : HWND; Rect : pRect; bErase : Boolean) : Boolean;
 begin
   Result := InterfaceObject.InvalidateRect(aHandle, Rect, bErase);
@@ -431,6 +457,11 @@ begin
   Result := InterfaceObject.Rectangle(DC, X1, Y1, X2, Y2);
 end;
 
+function RectVisible(dc : hdc; ARect: TRect) : Boolean;
+begin
+  Result := InterfaceObject.RectVisible(dc,ARect);
+end;
+
 function ReleaseCapture:  Boolean;
 begin
   Result := InterfaceObject.ReleaseCapture;
@@ -602,18 +633,13 @@ end;
   Returns:
 
  ------------------------------------------------------------------------------}
-function AdjustWindowRectEx( Var Rect: TRect; Style1: Word; MenuExist : Boolean; Style2 : Word) : Boolean;
+function AdjustWindowRectEx( Var Rect: TRect; Style1: Word; MenuExist : Boolean;
+  Style2 : Word) : Boolean;
 begin
+  // ToDo:
   Result := true;
-  try
-    if MenuExist 
-    then Rect.Top := Rect.Top + 25;
-  except
-    on E: Exception do begin
-      writeln('AdjustWindowRectEx: ',E.Message);
-      Result := False;
-    end;
-  end;
+  if MenuExist
+  then Rect.Top := Rect.Top + 25;
 end;
 
 {------------------------------------------------------------------------------
@@ -655,9 +681,9 @@ end;
   Returns:
 
  ------------------------------------------------------------------------------}
-function CopyRect(var lprcDst: TRect; const lprcSrc: TRect): Boolean;
+function CopyRect(var DestRect: TRect; const SrcRect: TRect): Boolean;
 begin
-  Move(lprcSrc, lprcDst, SizeOf(TRect));
+  Move(SrcRect, DestRect, SizeOf(TRect));
   Result := True;
 end;
 
@@ -716,16 +742,6 @@ begin
 end;
 
 
-{------------------------------------------------------------------------------
-  Function: ExcludeClipRect
-  Params:
--------------------------------------------------------------------------------}
-Function ExcludeClipRect(dc: hdc; LEft,Top, Right, Bottom : Integer) : Integer;
-begin
-//TODO: Finish ExcludeClipRect
-Result := SimpleRegion;
-end;
-
 {------------------------------------------------------------------------------
   Function: EndPaint
   Params:
@@ -785,106 +801,65 @@ end;
 
 {------------------------------------------------------------------------------
   Function: InflateRect
-  Params:   Rect: points to structure that increases or decreases in size.
-            dx  : amount to increase or decrease the rectangle width.
-            dy  : amount to increase or decrease the rectangle height.
+  Params:   ARect: points to structure that increases or decreases in size.
+            dx   : amount to increase the rectangle width.
+            dy   : amount to increase the rectangle height.
   Returns:  True if succesful
 
   Increases or decreases the width and height of the specified rectangle.
  ------------------------------------------------------------------------------}
-function InflateRect(var Rect: TRect; dx, dy: Integer): Boolean;
+function InflateRect(var ARect: TRect; dx, dy: Integer): Boolean;
 begin
-  with Rect do
-  begin
-    Dec(Left, dx);
-    Inc(Right, dx);
-    Dec(Top, dy);
-    Inc(Bottom, dy);
+  // make sure, that after deflating holds: Left<=Right
+  if (dx<0) and (ARect.Right-ARect.Left+2*dx<0) then begin
+    ARect.Left:=(ARect.Left+ARect.Right) shr 1;
+    ARect.Right:=ARect.Left;
+  end else begin
+    dec(ARect.Left,dx);
+    inc(ARect.Right,dx);
   end;
 
+  // make sure, that after deflating holds: Top<=Bottom
+  if (dy<0) and (ARect.Bottom-ARect.Top+2*dy<0) then begin
+    ARect.Top:=(ARect.Top+ARect.Bottom) shr 1;
+    ARect.Bottom:=ARect.Top;
+  end else begin
+    dec(ARect.Top,dy);
+    inc(ARect.Bottom,dy);
+  end;
+  
   Result := True;
 end;
 
-{------------------------------------------------------------------------------
-  Function: IntersectClipRect
-  Params:
-  Returns:
- ------------------------------------------------------------------------------}
-function IntersectClipRect(dc: hdc; Leftrect, Toprect, RightREct,Bottomrect : Integer): Integer;
-Begin
-//TODO: FInish me IntersectClipRect in winapi.inc
-result := Error;
-end;
-
 {------------------------------------------------------------------------------
   Function: IntersectRect
-  Params:
-  Returns:
+  Params:  var DestRect: TRect; const SrcRect1, SrcRect2: TRect
+  Returns: Boolean
+  
+  Intersects SrcRect1 and SrcRect2 into DestRect.
+  Intersecting means that DestRect will be the overlapping area of lprcSrc1 and
+  lprcSrc2. If SrcRect1 and SrcRect2 does not overlapp the Result is false, else
+  true.
  ------------------------------------------------------------------------------}
-function IntersectRect(var lprcDst: TRect; const lprcSrc1, lprcSrc2: TRect): Boolean;
-var
-  URect: TRect;
-  h1,h2,v1,v2: Integer;
+function IntersectRect(var DestRect: TRect;
+  const SrcRect1, SrcRect2: TRect): Boolean;
 begin
   Result := False;
 
-  // Sanity Checks
-  if IsRectEmpty(lprcSrc1) or IsRectEmpty(lprcSrc1) then 
-  begin
-    SetRectEmpty(lprcDst);
-    Exit;
+   // test if rectangles intersects
+  Result:=(SrcRect2.Left >= SrcRect1.Right)
+       or (SrcRect2.Right <= SrcRect1.Left)
+       or (SrcRect2.Top >= SrcRect1.Bottom)
+       or (SrcRect2.Bottom <= SrcRect1.Top);
+       
+  if Result then begin
+    DestRect.Left:=Max(SrcRect1.Left,SrcRect2.Left);
+    DestRect.Top:=Max(SrcRect1.Top,SrcRect2.Top);
+    DestRect.Right:=Min(SrcRect1.Right,SrcRect2.Right);
+    DestRect.Bottom:=Min(SrcRect1.Bottom,SrcRect2.Bottom);
+  end else begin
+    SetRectEmpty(DestRect);
   end;
-
-   // next test for no intersection at all.
-   with lprcSrc2 do
-     if ((Left > lprcSrc1.Left  ) and (Left >= lprcSrc1.Right  )) 
-     or ((Right <= lprcSrc1.Left) and (Right < lprcSrc1.Right  )) 
-     or ((Top > lprcSrc1.Top    ) and (Top >= lprcSrc1.Bottom  )) 
-     or ((Bottom <= lprcSrc1.Top) and (Bottom < lprcSrc1.Bottom)) 
-     then begin
-       SetRectEmpty(lprcDst);
-       Exit;
-     end;
-
-   // we got this far, ok intersecting rects
-   UnionRect(URect, lprcSrc1, lprcSrc2);
-   
-   with URect do
-   begin
-     if lprcSrc1.Top = lprcSrc2.Top 
-     then h1 := Top 
-     else if lprcSrc1.Top = Top 
-       then h1 := lprcSrc2.Top 
-       else h1 := lprcSrc1.Top;
-
-     if lprcSrc2.Bottom = lprcSrc1.Bottom 
-     then h2 := Bottom 
-     else if lprcSrc2.Bottom = Bottom 
-       then h2 := lprcSrc1.Bottom 
-       else h2 := lprcSrc2.Bottom;
-
-     if lprcSrc1.Left = lprcSrc2.Left 
-     then v1 := Left 
-     else if lprcSrc1.Left = Left 
-       then v1 := lprcSrc2.Left 
-       else v1 := lprcSrc1.Left;
-
-     if lprcSrc2.Right = lprcSrc1.Right 
-     then v2 := Right 
-     else if lprcSrc2.Right = Right 
-     then v2 := lprcSrc1.Right 
-     else v2 := lprcSrc2.Right;
-   end;
-
-   with lprcDst do
-   begin
-     Left := Min(v1, v2);
-     Right := Max(v1, v2);
-     Top := Min(h1, h2);
-     Bottom := Max(h1, h2);
-   end;
-
-   Result := True;
 end;
 
 {------------------------------------------------------------------------------
@@ -902,13 +877,14 @@ end;
 
 {------------------------------------------------------------------------------
   Function: IsRectEmpty
-  Params:
-  Returns:
+  Params: const lprc: TRect
+  Returns: Boolean
 
+  Returns true if ARect is (0,0,0,0)
  ------------------------------------------------------------------------------}
-function IsRectEmpty(const lprc: TRect): Boolean; 
+function IsRectEmpty(const ARect: TRect): Boolean;
 begin
-  with lprc do
+  with ARect do
     Result := (Left = 0) and (Top = 0) and (Right = 0) and (Bottom = 0);
 end;
 
@@ -1001,15 +977,6 @@ Begin
           );
 end;
 
-{------------------------------------------------------------------------------
-  Function: RectVisible
--------------------------------------------------------------------------------}
-Function RectVisible(dc : hdc; Rect: TRect) : Boolean;
-Begin
-//TODO: Finish me!  RectVisible in winapi.inc
-result := True;
-end;
-
 {------------------------------------------------------------------------------
   Function: ScrollWindow   In progress pbd
   Params:   Handle
@@ -1020,7 +987,8 @@ end;
 
   scrolls a window or portion of a window
  ------------------------------------------------------------------------------}
-function ScrollWindow(hWnd: HWND; XAmount, YAmount: Integer; Rect, ClipRect: PRect): Boolean;
+function ScrollWindow(hWnd: HWND; XAmount, YAmount: Integer;
+  Rect, ClipRect: PRect): Boolean;
 begin
   Result := ScrollWindowEx(hWnd, XAmount, YAmount, Rect, ClipRect, 0, 0, 0);
 end;
@@ -1030,33 +998,27 @@ end;
   Params:
   Returns: 
  ------------------------------------------------------------------------------}
-Function SetRect(var Rect : TRect; xLeft,yTop,xRight,yBottom : Integer) : Boolean;
+Function SetRect(var ARect : TRect; xLeft,yTop,xRight,yBottom : Integer) : Boolean;
 Begin
   Result := True;
-  try
-    with Rect do
-    begin
-      Left := xLeft;
-      Top := yTop;
-      Right := xRight;
-      Bottom := yBottom;
-    end;
-  except
-    on E: Exception do begin
-      writeln('AdjustWindowRectEx: ',E.Message);
-      Result := False;
-    end;
-  End;
+  with ARect do begin
+    Left := xLeft;
+    Top := yTop;
+    Right := xRight;
+    Bottom := yBottom;
+  end;
 End;
 
 {------------------------------------------------------------------------------
   Function: SetRectEmpty
   Params: Rect to clear 
   Returns: essentially nothing
+  
+  
  ------------------------------------------------------------------------------}
-function SetRectEmpty(var lprc: TRect): Boolean;
+function SetRectEmpty(var ARect: TRect): Boolean;
 begin
-  FillChar(lprc, SizeOf(TRect), 0);
+  FillChar(ARect, SizeOf(TRect), 0);
   Result := True;
 end;
 
@@ -1111,31 +1073,29 @@ end;
 
 {------------------------------------------------------------------------------
   Function: UnionRect          pbd
-  Params: lprcDst: TRect Result  INTENT OUT
-          lprcSrc1, lprcSrc2 TRects to Union INTENT IN
+  Params: var DestRect: TRect; const SrcRect1, SrcRect2: TRect
   Returns: Boolean 0 on failure
 
+  Creates the union rectangle of SrcRect1 and SrcRect2 into DestRect.
+  The union rectangle encloses SrcRect1 and SrcRect2.
  ------------------------------------------------------------------------------}
-function UnionRect(var lprcDst: TRect; const lprcSrc1, lprcSrc2: TRect): Boolean;
+function UnionRect(var DestRect: TRect;
+  const SrcRect1, SrcRect2: TRect): Boolean;
 begin
   Result := True;
-  try
-    lprcDst.Left := Min(lprcSrc1.Left, lprcSrc2.Left);
-    lprcDst.Top := Min(lprcSrc1.Top, lprcSrc2.Top);
-    lprcDst.Right := Max(lprcSrc1.Right, lprcSrc2.Right);
-    lprcDst.Bottom := Max(lprcSrc1.Bottom, lprcSrc2.Bottom);
-  except
-    on E: Exception do begin
-      writeln('AdjustWindowRectEx: ',E.Message);
-      Result := False;
-    end;
-  end;
+  DestRect.Left := Min(SrcRect1.Left, SrcRect2.Left);
+  DestRect.Top := Min(SrcRect1.Top, SrcRect2.Top);
+  DestRect.Right := Max(SrcRect1.Right, SrcRect2.Right);
+  DestRect.Bottom := Max(SrcRect1.Bottom, SrcRect2.Bottom);
 end;
 
 //##apiwiz##epi##   // Do not remove
 { =============================================================================
 
   $Log$
+  Revision 1.33  2002/06/21 15:41:56  lazarus
+  MG: moved RectVisible, ExcludeClipRect and IntersectClipRect to interface dependent functions
+
   Revision 1.32  2002/06/04 15:17:22  lazarus
   MG: improved TFont for XLFD font names
 
diff --git a/lcl/include/winapih.inc b/lcl/include/winapih.inc
index f3bab5207f..c7cb893df5 100644
--- a/lcl/include/winapih.inc
+++ b/lcl/include/winapih.inc
@@ -78,6 +78,7 @@ function EnableScrollBar(Wnd: HWND; wSBflags, wArrows: Cardinal): Boolean; {$IFD
 function EnableWindow(hWnd: HWND; bEnable: Boolean): Boolean; {$IFDEF IF_BASE_MEMBER}virtual;{$ENDIF}
 function Ellipse(DC: HDC; x1, y1, x2, y2: Integer): Boolean; {$IFDEF IF_BASE_MEMBER}virtual;{$ENDIF}
 //function EqualRect --> independent
+Function ExcludeClipRect(dc: hdc; Left, Top, Right, Bottom : Integer) : Integer; {$IFDEF IF_BASE_MEMBER}virtual;{$ENDIF}
 function ExtTextOut(DC: HDC; X, Y: Integer; Options: Longint; Rect: PRect; Str: PChar; Count: Longint; Dx: PInteger): Boolean;  {$IFDEF IF_BASE_MEMBER}virtual;{$ENDIF}
 
 function FillRect(DC: HDC; const Rect: TRect; Brush: HBRUSH): Boolean; {$IFDEF IF_BASE_MEMBER}virtual;{$ENDIF}
@@ -116,6 +117,7 @@ function GetWindowOrgEx(dc : hdc; var P : TPoint): Integer; {$IFDEF IF_BASE_MEMB
 function HideCaret(hWnd: HWND): Boolean; {$IFDEF IF_BASE_MEMBER}virtual;{$ENDIF}
 
 //function InflateRect --> independent
+function IntersectClipRect(dc: hdc; Left, Top, Right,Bottom: Integer): Integer; {$IFDEF IF_BASE_MEMBER}virtual;{$ENDIF}
 //function IntersectRect --> independent
 Function InvalidateRect(aHandle : HWND; Rect : pRect; bErase : Boolean) : Boolean; {$IFDEF IF_BASE_MEMBER}virtual;{$ENDIF}
 //function IsCharAlphaNumeric --> independent
@@ -140,6 +142,7 @@ function PostMessage(hWnd: HWND; Msg: Cardinal; wParam: LongInt; lParam: LongInt
 
 function RealizePalette(DC: HDC): Cardinal; {$IFDEF IF_BASE_MEMBER}virtual;{$ENDIF}
 function Rectangle(DC: HDC; X1, Y1, X2, Y2: Integer): Boolean; {$IFDEF IF_BASE_MEMBER}virtual;{$ENDIF}
+function RectVisible(dc : hdc; ARect: TRect) : Boolean; {$IFDEF IF_BASE_MEMBER}virtual;{$ENDIF}
 function ReleaseCapture : Boolean; {$IFDEF IF_BASE_MEMBER}virtual;{$ENDIF}
 function ReleaseDC(hWnd: HWND; DC: HDC): Integer;  {$IFDEF IF_BASE_MEMBER}virtual;{$ENDIF}
 function RestoreDC(DC: HDC; SavedDC: Integer): Boolean; {$IFDEF IF_BASE_MEMBER}virtual;{$ENDIF}
@@ -216,29 +219,28 @@ type
 
 //##apiwiz##spi##    // Do not remove
 
-function AdjustWindowRectEx( Var Rect: TRect; Style1: Word; MenuExist : Boolean; Style2 : Word) : Boolean;
+function AdjustWindowRectEx(Var Rect: TRect; Style1: Word; MenuExist : Boolean;
+  Style2 : Word) : Boolean;
 
 Function BeginPaint(Handle : hwnd; var PS : TPaintStruct): hdc;
 
 Function CharLowerBuff(pStr : PChar; Len : Integer): Integer;
-function CopyRect(var lprcDst: TRect; const lprcSrc: TRect): Boolean;
+function CopyRect(var DestRect: TRect; const SrcRect: TRect): Boolean;
 function CreateFont(Height, Width, Escapement, Orientation, Weight: Integer;
   Italic, Underline, StrikeOut, CharSet, OutputPrecision, ClipPrecision,
   Quality, PitchAndFamily: Cardinal; FaceName: PChar): HFONT;
 function CreatePen(Style, Width: Integer; Color: TColorRef): HPEN;
 
 Function EndPaint(Handle : hwnd; var PS : TPaintStruct): Integer;
-Function ExcludeClipRect(dc: hdc; LEft,Top, Right, Bottom : Integer) : Integer;
 function EqualRect(const lprc1, lprc2: TRect): Boolean;
 
 function GetScrollPos(Handle: HWND; nBar: Integer): Integer;
 function GetScrollRange(Handle: HWND; nBar: Integer; var lpMinPos, lpMaxPos: Integer): Boolean;
 
-function InflateRect(var Rect: TRect; dx, dy: Integer): Boolean;
-function IntersectClipRect(dc: hdc; Leftrect, Toprect, RightREct,Bottomrect : Integer): Integer;
-function IntersectRect(var lprcDst: TRect; const lprcSrc1, lprcSrc2: TRect): Boolean;
+function InflateRect(var ARect: TRect; dx, dy: Integer): Boolean;
+function IntersectRect(var DestRect: TRect; const SrcRect1, SrcRect2: TRect): Boolean;
 Function IsCharAlphaNumeric(c : Char) : Boolean;
-function IsRectEmpty(const lprc: TRect): Boolean; 
+function IsRectEmpty(const ARect: TRect): Boolean;
 
 function OffSetRect(var Rect: TRect; dx,dy: Integer): Boolean;
 
@@ -249,16 +251,14 @@ function MakeLResult(l, h: Word): LRESULT;
 Function PtInRect(Rect : TRect; Point : TPoint) : Boolean;
 Function PointtoSmallPoint(const P : TPoint) : TSmallPoint;
 
-function RectVisible(dc : hdc; Rect: TRect) : Boolean;
-
 function ScrollWindow(hWnd: HWND; XAmount, YAmount: Integer; Rect, ClipRect: PRect): Boolean;
-function SetRect(Var Rect : TRect; xLeft,yTop,xRight,yBottom : Integer) : Boolean;
-function SetRectEmpty(var lprc: TRect): Boolean;
+function SetRect(Var ARect : TRect; xLeft,yTop,xRight,yBottom : Integer) : Boolean;
+function SetRectEmpty(var ARect: TRect): Boolean;
 function SetScrollPos(Handle: HWND; nBar, nPos: Integer; bRedraw: Boolean): Integer;
 function SetScrollRange(Handle: HWND; nBar, nMinPos, nMaxPos: Integer; bRedraw: Boolean): Boolean;
-Function SmallPointtoPoint(const P : TSmallPoint) : Tpoint;
+Function SmallPointToPoint(const P : TSmallPoint) : Tpoint;
 
-function UnionRect(var lprcDst: TRect; const lprcSrc1, lprcSrc2: TRect): Boolean; //pbd
+function UnionRect(var DestRect: TRect; const SrcRect1, SrcRect2: TRect): Boolean; //pbd
 
 
 //##apiwiz##epi##    // Do not remove
@@ -269,6 +269,9 @@ function UnionRect(var lprcDst: TRect; const lprcSrc1, lprcSrc2: TRect): Boolean
 { =============================================================================
 
   $Log$
+  Revision 1.28  2002/06/21 15:41:56  lazarus
+  MG: moved RectVisible, ExcludeClipRect and IntersectClipRect to interface dependent functions
+
   Revision 1.27  2002/06/04 15:17:22  lazarus
   MG: improved TFont for XLFD font names
 
diff --git a/lcl/interfaces/gtk/gtkwinapi.inc b/lcl/interfaces/gtk/gtkwinapi.inc
index 4b09517278..d295346391 100644
--- a/lcl/interfaces/gtk/gtkwinapi.inc
+++ b/lcl/interfaces/gtk/gtkwinapi.inc
@@ -1907,6 +1907,20 @@ begin
   end;
 end;
 
+{------------------------------------------------------------------------------
+  Function: ExcludeClipRect
+  Params:  dc: hdc; Left, Top, Right, Bottom : Integer
+  Returns: integer
+
+
+ ------------------------------------------------------------------------------}
+function TgtkObject.ExcludeClipRect(dc: hdc;
+  Left, Top, Right, Bottom : Integer) : Integer;
+begin
+  // ToDo:
+  Result:=SimpleRegion;
+end;
+
 {------------------------------------------------------------------------------
   Function: ExtTextOut
   Params:  none
@@ -3159,6 +3173,29 @@ begin
 
 end;
 
+{------------------------------------------------------------------------------
+  Function: IntersectClipRect
+  Params:  dc: hdc; Left, Top, Right, Bottom: Integer
+  Returns: Integer
+
+  Shrinks the current clipping region in the device context dc to the boundary
+  defined by Left, Top, Right, Bottom.
+
+  The result can be one of the following constants
+      Error
+      NullRegion
+      SimpleRegion
+      ComplexRegion
+      Region_Error
+
+ ------------------------------------------------------------------------------}
+function TGTKObject.IntersectClipRect(dc: hdc;
+  Left, Top, Right, Bottom: Integer): Integer;
+begin
+  // ToDo:
+  Result:=SimpleRegion;
+end;
+
 {------------------------------------------------------------------------------
   Function: InvalidateRect
   Params: aHandle:
@@ -3171,41 +3208,23 @@ function TGTKObject.InvalidateRect(aHandle : HWND; Rect : pRect;
   bErase : Boolean) : Boolean;
 var
   gdkRect : TGDKRectangle;
-  {$IFDEF ClientRectBugFix}
   Widget: PGtkWidget;
-  {$ENDIF}
 begin
 //  Writeln(format('Rect = %d,%d,%d,%d',[rect^.left,rect^.top,rect^.Right,rect^.Bottom]));
   Result := True;
-  try
-    gdkRect.X := Rect^.Left;
-    gdkRect.Y := Rect^.Top;
-    gdkRect.Width := (Rect^.Right - Rect^.Left);
-    gdkRect.Height := (Rect^.Bottom - Rect^.Top);
-    
-    {$IFDEF ClientRectBugFix}
-    Widget:=GetFixedWidget(PGtkWidget(aHandle));
-    if Widget=nil then Widget:=PgtkWidget(aHandle);
+  gdkRect.X := Rect^.Left;
+  gdkRect.Y := Rect^.Top;
+  gdkRect.Width := (Rect^.Right - Rect^.Left);
+  gdkRect.Height := (Rect^.Bottom - Rect^.Top);
+  
+  Widget:=GetFixedWidget(PGtkWidget(aHandle));
+  if Widget=nil then Widget:=PgtkWidget(aHandle);
 
-    if bErase then
-      gdk_window_clear_area(Widget^.Window,
-                            gdkRect.X,gdkRect.Y,gdkRect.Width,gdkRect.Height);
-
-    gtk_widget_draw(Widget, @gdkRect);
-    {$ELSE}
-    if bErase then
-      gdk_window_clear_area(PGtkWidget(aHandle)^.Window,
-                            gdkRect.X,gdkRect.Y,gdkRect.Width,gdkRect.Height);
-
-    gtk_widget_draw(PGtkWidget(aHandle), @gdkRect);
-    {$ENDIF}
-  except
-    on E: Exception do begin
-      writeln('TGTKObject.InvalidateRect: ',E.Message);
-      Result := False;
-    end;
-  end;
+  if bErase then
+    gdk_window_clear_area(Widget^.Window,
+                          gdkRect.X,gdkRect.Y,gdkRect.Width,gdkRect.Height);
 
+  gtk_widget_draw(Widget, @gdkRect);
 end;
 
 {------------------------------------------------------------------------------
@@ -3683,6 +3702,16 @@ begin
   Assert(False, Format('trace:< [TgtkObject.Rectangle] DC:0x%x, X1:%d, Y1:%d, X2:%d, Y2:%d', [DC, X1, Y1, X2, Y2]));
 end;
 
+{------------------------------------------------------------------------------
+  Function: RectVisible
+  Params:  dc : hdc; ARect: TRect
+  Returns: True if ARect is not completely clipped away.
+ ------------------------------------------------------------------------------}
+function TgtkObject.RectVisible(dc : hdc; ARect: TRect) : Boolean;
+begin
+  Result:=true;
+end;
+
 {------------------------------------------------------------------------------
   Function: ReleaseCapture
   Params:  none
@@ -4781,6 +4810,9 @@ end;
 { =============================================================================
 
   $Log$
+  Revision 1.80  2002/06/21 15:41:56  lazarus
+  MG: moved RectVisible, ExcludeClipRect and IntersectClipRect to interface dependent functions
+
   Revision 1.79  2002/06/19 19:46:10  lazarus
   MG: Form Editing: snapping, guidelines, modified on move/resize, creating components in csDesigning, ...
 
diff --git a/lcl/interfaces/gtk/gtkwinapih.inc b/lcl/interfaces/gtk/gtkwinapih.inc
index 4934e2de59..94f2db1e23 100644
--- a/lcl/interfaces/gtk/gtkwinapih.inc
+++ b/lcl/interfaces/gtk/gtkwinapih.inc
@@ -62,6 +62,7 @@ function EnableMenuItem(hMenu: HMENU; uIDEnableItem: Integer; bEnable: Boolean):
 function EnableScrollBar(Wnd: HWND; wSBflags, wArrows: Cardinal): Boolean; override;
 function EnableWindow(hWnd: HWND; bEnable: Boolean): Boolean; override;
 function Ellipse(DC: HDC; x1,y1,x2,y2: Integer): Boolean; override;
+Function ExcludeClipRect(dc: hdc; Left, Top, Right, Bottom : Integer) : Integer; override;
 function ExtTextOut(DC: HDC; X, Y: Integer; Options: Longint; Rect: PRect; Str: PChar; Count: Longint; Dx: PInteger): Boolean;  override;
 
 function FillRect(DC: HDC; const Rect: TRect; Brush: HBRUSH): Boolean; override;
@@ -95,6 +96,7 @@ Function GetWindowSize(Handle : hwnd; var Width, Height: integer): boolean; over
 
 function HideCaret(hWnd: HWND): Boolean; override;
 
+function IntersectClipRect(dc: hdc; Left, Top, Right, Bottom: Integer): Integer; override;
 function InvalidateRect(aHandle : HWND; Rect : pRect; bErase : Boolean) : Boolean; override;
 
 function KillTimer (hWnd : HWND; uIDEvent : cardinal) : boolean; override;
@@ -113,6 +115,7 @@ function PostMessage(hWnd: HWND; Msg: Cardinal; wParam: LongInt; lParam: LongInt
 
 function RealizePalette(DC: HDC): Cardinal; override;
 function Rectangle(DC: HDC; X1, Y1, X2, Y2: Integer): Boolean; override;
+function RectVisible(dc : hdc; ARect: TRect) : Boolean; override;
 Function ReleaseCapture : Boolean; override;
 function ReleaseDC(hWnd: HWND; DC: HDC): Integer; override;
 function RestoreDC(DC: HDC; SavedDC: Integer): Boolean; override;
@@ -154,6 +157,9 @@ Function WindowFromPoint(Point : TPoint) : HWND; override;
 { =============================================================================
 
   $Log$
+  Revision 1.32  2002/06/21 15:41:57  lazarus
+  MG: moved RectVisible, ExcludeClipRect and IntersectClipRect to interface dependent functions
+
   Revision 1.31  2002/06/04 15:17:26  lazarus
   MG: improved TFont for XLFD font names