[SOLVED] BGRABitmap.Draw - Ignoring X and Y param?

[Dibo]

Hi,

I want draw BGRABitmap on canvas with some offset, but Draw and DrawPart are ignoring X and Y params (even if I use overloaded method with TRect instead of X/Y). Is this a bug or are they for something else (I thought that they working similar like X,Y offset in TBGRABitmap.PutImage method)? This is my test code:

Code: Pascal  [Select][+][-]

1. procedure TForm1.FormPaint(Sender: TObject);
2. var
3.   b: TBGRABitmap;
4.   r: TRect;
5. begin
6.   b := TBGRABitmap.Create(100,100);
7.   r := b.ClipRect;
8.   b.Rectangle(b.ClipRect,clblack);
9.   b.Draw(Self.Canvas,200,200,False);
10.   b.Free;
11. end;
12.  

Rectangle should be offset by 200,200 but it always start from 0,0.
I have stable BGRABitmap 5.6, FPC 2.6.0 Stable, Lazarus 0.9.31 from SVN builded on QT interface

BTW: Why code=pascal doesn't highlight pascal syntax any more on this forum? I noticed this when forum get new layout/engine.

Regards, Dibo

[circular]

This works fine on Windows. There may be a bug in QT code.

Oh I found it.

In bgraqtbitmap.pas, replace :

Code: [Select]

procedure TBGRAQtBitmap.SlowDrawTransparent(ABitmap: TBGRADefaultBitmap;
  ACanvas: TCanvas; ARect: TRect);
begin
  ACanvas.Draw(0,0, ABitmap.Bitmap);
end;
By this

Code: [Select]

procedure TBGRAQtBitmap.SlowDrawTransparent(ABitmap: TBGRADefaultBitmap;
  ACanvas: TCanvas; ARect: TRect);
begin
  ACanvas.StretchDraw(ARect, ABitmap.Bitmap);
end;
Does it work ?

[Dibo]

Works. Thanks!

[Dibo]

But are you sure that it should be StretchDraw? Because now it stretch bitmap to the rect. Maybe it should be something like this? It works too.
ACanvas.Draw(ARect.Left,ARect.Top, ABitmap.Bitmap);

[User137]

In that case function parameter should be a TPoint, not TRect. No point sending 4 values where only 2 are used.

[circular]

Normally, the TRect should be automatically adjusted to the right size when you call the usual Draw method. It is not the case ?

[Dibo]

You are right. I had wrong code. Overloaded draw method with TRect should stretch image, this is logical. So I used draw method with X and Y param and my image doesn't stretch, it is just offset and cut like I wanted. It was a wrong interpretation on my part. Problem solved

[circular]

It's cool that your problem is solved.

I've update on subversion the QT code with the correct code.