Pasting to BGRA Bitmap - [Solved]

[zxandris]

Okay I've had a look around and the code below doesn't appear to work, and I can't see why.  I saved from the picture object to check and it's just empty.  Any help would be appreciated.

Code: Pascal  [Select][+][-]

1. procedure TframeImageViewer.actIVPasteExecute(Sender: TObject);
2. var
3.    pic : TPicture;
4. begin
5.     // WIP
6.     Pic := TPicture.Create;
7.     try
8.        if clipboard.HasFormat(CF_Picture) then
9.        begin
10.             if not assigned(BgraView) then BgraView := TBgraBitmap.create(0,0, BGRAPixelTransparent);
11.             try
12.                 pic.Bitmap.LoadFromClipboardFormat(CF_Picture);
13.                 BgraView.SetSize(pic.Bitmap.width, pic.bitmap.height);
14.                 BgraView.Canvas.Draw(0, 0, pic.graphic);
15.                 rst.x := bgraView.width;
16.                 rst.y := bgraView.Height;
17.                 pnlImage.Repaint;
18.             except
19.                   //
20.             end;
21.        end;
22.     finally
23.            pic.free;
24.     end;
25. end;
26.  

[zxandris]

Okay did more searching and fiddling and this works...

Code: Pascal  [Select][+][-]

1. procedure TframeImageViewer.actIVPasteExecute(Sender: TObject);
2. var
3.    pic : TPicture;
4.    bmp : TBitmap;
5. begin
6.     // WIP
7.     if Clipboard.HasPictureFormat then begin
8.        bmp := tbitmap.Create;
9.        try
10.           bmp.Assign(Clipboard);
11.           if not assigned(BgraView) then BgraView := TBgraBitmap.create(0,0, BGRAPixelTransparent);
12.           try
13.               BgraView.SetSize(bmp.width, bmp.height);
14.               BgraView.Canvas.Draw(0, 0, bmp);
15.               rst.x := bgraView.width;
16.               rst.y := bgraView.Height;
17.               pnlImage.Repaint;
18.           except
19.                 //
20.           end;
21.        finally
22.               bmp.free;
23.        end;
24.     end;
25.  

But how to I paste and maintain the alpha, would anyone know that?

[zxandris]

Okay on further searching and a little testing, these seem to maintain transparency between applications.

Copy

Code: Pascal  [Select][+][-]

1. var
2.    bmp : TBitmap;
3. begin
4.      // This seems to copy transparency
5.      if assigned(BgraView) then
6.      begin
7.         bmp := TBitmap.create;
8.         try
9.             bmp := BgraView.MakeBitmapCopy(clNone, false);
10.             Clipboard.Open;
11.             CLipboard.Assign(bmp);
12.             clipboard.Close;
13.         finally
14.                bmp.free;
15.         end;
16.     end;
17. end;
18.  

Paste

Code: Pascal  [Select][+][-]

1. procedure TframeImageViewer.actIVPasteExecute(Sender: TObject);
2. var
3.    bmp : TBitmap;
4. begin
5.     // WIP
6.     if Clipboard.HasPictureFormat then
7.     begin
8.            bmp := tbitmap.Create;
9.            try
10.               bmp.Assign(Clipboard);
11.               if not assigned(BgraView) then BgraView := TBgraBitmap.create(0,0, BGRAPixelTransparent);
12.               try
13.                   BgraView.SetSize(bmp.width, bmp.height);
14.                   BgraView.Canvas.Draw(0, 0, bmp);
15.                   rst.x := bgraView.width;
16.                   rst.y := bgraView.Height;
17.                   pnlImage.Repaint;
18.               except
19.                     //
20.               end;
21.            finally
22.                   bmp.free;
23.            end;
24.     end;
25. end;
26.  

Now obviously those are from my app, but could easily be changed. I thought I would offer them here for those also looking for a solution to this.