Help, we need to create a crossfade from two bitmaps using a WinG canvas

Hi

We have a 640x480 image which needs to crossfade out into another image, we
need to create this effect using a WinG canvas as its for Win31 machines and
we use the WinG canvas for faster display.  Using Delphi 1 and WinG.pas

Any help please?

Thanks
Geoff Coope
silkmoth plc

PS.  Prefer Code