New Components, what is the best ancestor?


I'm writing a Graphical display component, It shouldn't ever have focus,
just a canvas to paint on. At the moment my control is derived from
TGraphicControl, according to the Delphi help file this is quite fast for
graphics and no input. I have one problem with it though (or maybe the
problem is with something else) When I resize on of the windows containing
this control (with Alignment=alClient) it paints the background of the form
(normally clBtnFace){*word*128}and then it pants my component, this flickers
allot. I've tried the following techniques to reduce the flicker with no
avail, this is why I'm thinking it might be the tGraphicControl:

(1) In oncreate I have:    componentstyle:=componentstyle+[csopaque];
(2) I paint on a buffer (tBitmap) and then use the BitBlt API function to
paint it to the canvas
(3) I've overridden WM_EraseBackground and set Msg.result:=1;

Can anyone please help me with this problem
Johann Kellerman