Not setting page sizes in a loop

Still working on my imposing app.  Got all the good stuff done and threw it in a loop for multiple pages and not it wont keep the pagesize that I specify.  The output ends up being the same as the original...  This is baffling me.   Anyone have any thoughts?

Hi,

so it works as you want:

procedure TForm1.Button1Click(Sender: TObject);
var
  i, n,
  cid,
  PageNum: integer;
  pw, ph,
  npw, nph: double;
begin
  QP := TQuickPDF.Create;
  if QP.UnlockKey({$I PDFkey.inc})=1 then;
  QP.LoadFromFile(fn ,'');  // fn has a valid name of PDF-file
  n := QP.PageCount;
  pw := QP.PageWidth;
  ph := QP.PageHeight;
  npw := pw*2;     // to get enough place
  nph := ph*2;
  for i:=1 to n
  do begin
    PageNum := QP.NewPage;    // ever the last = n+1
    cid := QP.CapturePage(1); // ever the first! capture deletes!
// now we have again n pages, value of PageNum becomes wrong.
// But we knew the newpage we want to draw on is selected and on location n
    QP.SetOrigin(1);
    QP.SetPageDimensions(npw, nph);
// DRAW CAPTURED PAGE INTO NEW LAYOUT / AS 2 x 2 ARRAY
    QP.DrawCapturedPage(cid, 0, 0, pw, ph);
    QP.DrawCapturedPage(cid, pw, 0, pw, ph);
    QP.DrawCapturedPage(cid, 0, ph, pw, ph);
    QP.DrawCapturedPage(cid, pw, ph, pw, ph);
  end;
  QP.SaveToFile(ChangeFileExt(fn, '_imposed.pdf'));
  QP. Free;
end;

In your code is a very small but powerfull mistake:

CapturePage(i)

This small thing makes a lot of trouble, because on step i=2 you take for capture page with old number 3 and so on...

If your input has two or more page, after your loop old page 2 becomes page 1 without changes.

Why?
After capturing (even used or not) the choosen page is deleted, so all pagenumbers after it change. So you have to take ever the first page. On the other hand NewPage appends, so you have after this n pages, as on start. Ever the actually first page goes and comes back imposed on last (new) page.


Cheers,
Werner



Edited by edvoigt - 28 Feb 12 at 4:38PM

Hi,

you didn't understand me. You have in your loop only to exchange in line

ThisCaptureID = QP.CapturePage(i)

index i by constant 1. Because of captering ever the first page, you get every (old) page of document in their right order one after the other. Newpage ever appends and so on the end of document grows step by step the new doc as you want it.

Let's assume, the doc has 3 Pages:

At start it looks after Newpage so:
1, 2, 3, n1 (n1 denotes the coming new page 1).

After captering page on place 1 is no more there and we have 3 pages in document:
2, 3, n1

From Newpage n1 is selected and you may draw the captured (old) page 1 so often as you want anywhere on n1. The next loop-step shall take page 2. It is now on first place, therefore we dont't capture page i (it would be the page on place 2, it is page 3). We take ever the page on first place!

After this wie have
3, n1, n2

and in last loop
3, n1, n2, n3
n1, n2, n3.

To your question:
How do I move to a particular page then?

You have to distinguish between the pagenumber as in QPL is used. It denotes ever the ordering number (or number of location) in a document, not what is written as pagenumber anywhere on page.

You may select a page over her pagenumber in this sense, to manipulate it and with QP.MovePage you may move selected page from one location to another. But in your lop is no moving needed.


In hope, that my answer is what you want,

Werner

Hi,

I see, you're on the right way.

Only a small advice. It is a good idea, to do the newpage ever as first statement in loop. Every PDF has at least one page, so this new page is ever used for drawing the captured first page. There is no risk. Your test

if pagenum=1 ...

is not needed.

Start in the loop ever with this both statements and it works fine, as you'll see

      For i = 1 To numpages
        'CREATE THE NEW PAGE FIRST this is where TO PLACE THE CAPTURE ON                       ThisPageNum = QP.NewPage()        'DRAW CAPTURED PAGE INTO NEW LAYOUT / AS 2 x 2 ARRAY

... and so on with your imposition stuff.

Happy coding,

Werner