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Draw text transparently on a canvas

I need to draw a text on a canvas.
Here are the problems:

1)TextOut draws a frame behind the text(like does a fillrect first and then draws the text over the rect). I only need to draw the text. I tried to make Canvas.Brush.Color:=clNone but that only made it white.

2)for the text to be seen without the mentioned frame, its colour should be the invert of the area around it. I remember this is done somehow with NOT operator, but I don't exatcly remember how.

Igor UL7AAjr

Hi duke_n,
did you try Canvas.Brush.Style = bsClear?

-----
Igor.

duke_n

ASKER

My man you are a genius!

now what about the second problem?

duke_n

ASKER

ah, I found what I meant.

to set Canvas.Pen.Mode:=pmNot;

but it doesn't seem to affect the font.

ASKER CERTIFIED SOLUTION

Igor UL7AAjr

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duke_n

ASKER

this is really weird. I used this function many many times, but now nothing works:

var
BMp:TBitMap;
s:string;
pt:TPoint;
begin
s:='Show me the money' ;
BMP:=TBitmap.Create;
BMP.Width:=Canvas.TextWidth(s);
BMP.Height:=Canvas.TextHeight(S) ;
bmp.Canvas.Brush.Style:=bsClear;
BMP.Canvas.TextOut(0,0,s);
PT.x:=200;
Pt.y:=50;
Pt:=Image1.ClientToScreen(PT);
if INteger(BitBlt(Image1.{Picture.Bitmap.}Canvas.Handle,Pt.x,Pt.y,BMP.Width,BMP.Height,BMP.Canvas.Handle,0,0,SRCERASE))<>0 then
ShowMessage('Success');
bmp.Free;

The weirdest thing is that it shows "Success" but it doesn't change the canvas.

duke_n

ASKER

HAHA, Got it

var
BMp:TBitMap;
s:string;
pt:TPoint;
begin
s:='Show me the money' ;
BMP:=TBitmap.Create;
BMP.Width:=Canvas.TextWidth(s);
BMP.Height:=Canvas.TextHeight(S) ;
bmp.Canvas.Brush.Style:=bsClear;
BMP.Canvas.TextOut(0,0,s);
Image1.Picture.Bitmap.Width:=Image1.Width;
Image1.Picture.Bitmap.Height:=Image1.Width;
PT.x:=200;
Pt.y:=80;

if INteger(BitBlt(Image1.Picture.Bitmap.Canvas.Handle,Pt.x,Pt.y,BMP.Width,BMP.Height,BMP.Canvas.Handle,0,0,SRCINVERT))<>0 then
ShowMessage('Success');

InvertRect(Image1.Picture.Bitmap.Canvas.Handle,RECT(Pt.x,Pt.y,Pt.x+BMP.Width,Pt.y+BMP.Height));
bmp.Free;

end;

duke_n

ASKER

Thank you very much.

You have been of great help