How to draw a rectangle, and then delete it

[BlueIcaro]

Hello, I use this code to draw a rectangule, over a canvas

Code: Pascal  [Select][+][-]

1.   Canvas.Brush.Style := bsClear;
2.   Canvas.Pen.Mode := pmCopy;
3.   Canvas.Rectangle(100,100,200,200);
4.  

When I want to delete it, I use:

Code: Pascal  [Select][+][-]

1.    Canvas.Brush.Style := bsClear;
2.   Canvas.Pen.Mode := pmNotCopy;
3.   Canvas.Rectangle(100,100,200,200);        
4.  

But This code, makes a rectangle with a white border.

Any help?

/BlueIcaro

[typo]

Because clWhite is the inverse color of clBlack.

In order to restore the background correctly, you need to save it previously.

To save and draw:

Code: [Select]

var
  r, r2 :trect;
begin
  r.Top := 100;
  r.Left := 100;
  r.Right := 200;
  r.Bottom := 200;
  r2.Top := 0;
  r2.Left := 0;
  r2.Right := 100;
  r2.Bottom := 100;
  Image2.Canvas.Copyrect(r2, canvas, r);
  Canvas.Brush.Color := clBlack;
  Canvas.Pen.Color := clBlack;
  Canvas.Rectangle(100,100,200,200);
end;                     

To restore:

Code: [Select]

var
  r, r2 :trect;
begin
  r.Top := 100;
  r.Left := 100;
  r.Right := 200;
  r.Bottom := 200;
  r2.Top := 0;
  r2.Left := 0;
  r2.Right := 100;
  r2.Bottom := 100;
  Canvas.Copyrect(r, image2.canvas, r2);
end;       


[BlueIcaro]

Thnak you!!, it's works!!!

/BlueIcaro