From: pandeng@telepath.com (Steve Schafer (TeamB))
Subject: Re: Changing the background of a bitmap
Date: 04 Mar 1999 00:00:00 GMT
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On Thu, 04 Mar 1999 13:49:53 +0900, Graham Stratford
<stratford@kb.jcs.co.jp> wrote:

>I have a 256-color bitmap, which has a black image on a white
>background. I want to change the background to another color. Is there
>any simple way to do this?

Assuming the source bitmap is called MyBitmap:

 var
   Dest: TBitmap;
   R: TRect;
 begin
 Dest := TBitmap.Create;
 with Dest do
   begin
   Width := MyBitmap.Width;
   Height := MyBitmap.Height;
   R := Rect(0, 0, Width, Height);
   with Canvas do
     begin
     with Brush do
       begin
       Style := bsSolid;
       Color := clRed;
       end;
     BrushCopy(R, MyBitmap, R, clWhite);
     end;
   end;
 end;

The destination bitmap will be the same as the original, except that
all white pixels will become red pixels.

-Steve