Blur BGRAShape?

[dietmar]

Hi,

does anyone has a code example on how to blur a bgrashape?

Thx,
--Dietmar

[winni]

Hi!

There are a lot of filters to blur a TBGRAbitmap, BUT

The TBGRAShape contains only a TBGRAbitmap in the private section.
So you have to create a derived class from the TBGRAShape where the TBGRAbitmap is public.

The TBRAbitmap has it's own board in this forum:

https://forum.lazarus.freepascal.org/index.php/board,46.0.html

It is better tp place your questions about TBGRA there.

Winni

[dietmar]

Hi,

ok, so here we are... has anybody a little bit of code for me?

--Dietmar

[winni]

Hi!

There is no easy way to blur a BGRAshape.

But you can use a workaround:

Replace the BGRAshape with a TShape.

Copy the canvas to a BGRAbitmap.
Blur the BGRAbitmap
Copy it back to the canvas:

Code: Pascal  [Select][+][-]

1. procedure TForm1.Button1Click(Sender: TObject);
2. var bmp : TBGRABitmap;
3.     R : TRect;
4. begin
5.  bmp := TBGRAbitmap.Create (Shape1.Width,Shape1.height);
6.  R := rect(0,0,Shape1.Width,Shape1.height);
7.  bmp.Canvas.CopyRect(R,Shape1.Canvas, R);
8. // draw a circle for test
9.   bmp.EllipseAntialias(Shape1.Width / 2 ,Shape1.height/2,15,15,cssBlack,2,cssRed);
10.  BGRAReplace (bmp,bmp.FilterBlurMotion(8,180,true));
11.  bmp.Draw(Shape1.Canvas,0,0);
12.  bmp.free;
13. end;                  
14.  
15.  

Winni

[dietmar]

Cool, thank you

--Dietmar

[winni]

Hi!

If you insist on TBGRAshape and don't want to fiddle with the TBGRAShape class then I have only one rude solution for you:

Take a partial screenshot and draw it on the Form.canvas - over the BGRAshape.

Code: Pascal  [Select][+][-]

1. procedure TForm1.Button1Click(Sender: TObject);
2. var bmp : TBGRABitmap;
3.     R : TRect;
4.     TopL, BottomR : TPoint;
5. begin
6. TopL :=ClientToScreen(Point(BGRAShape1.left, BGRAShape1.top ));
7. BottomR := ClientToScreen(Point(BGRAShape1.left + BGRAShape1.width,
8.                                 BGRAShape1.top+ BGRAShape1.Height) );
9.  
10. R := Rect(TopL.X,TopL.Y,   BottomR.X, BottomR.y);
11. bmp := TBGRABitmap.create;
12. bmp.TakeScreenshot(R);
13. bmp.EllipseAntialias(BGRAShape1.Width / 2 ,BGRAShape1.height/2,15,15,cssBlack,2,cssRed);
14. BGRAReplace (bmp,bmp.FilterBlurMotion(8,180,true));
15. bmp.draw(canvas,BGRAshape1.left, BGRAshape1.top);
16. bmp.free;
17. end;

But both shown solutions are not satisfying.

TBGRAShape should be enhanced:

Either with a public TBGRAbitmap.

Or with  a public Canvas and a published onPaint event.

Winni

[circular]

Hmm well there are things to consider. The blur would be limited to the rectangle area of the control. Though you might want to go further. It could be a shadow, but still draw the shape over it, etc.

Another solution is to put a TBGRAGraphicControl and draw exactly what you wants.

Another solution would be to create your own control but duplicating the existing one, changing its name and changing how it renders.