Sorting post card

I am creating an application using a PDF as template to create post cards. The page has 9 post cards across sorted (see below).

1 2 3

4 5 6

7 8 9

Now, when everything is printed and we cut the page, the sorting gets messed up. That is, the first tray contains 1, 10, 19 etc..I am trying to code (sort) in such a way that the first page contains (for eg: lets consider total of 35 post cards)

1 5 9

13 17 21

25 29 33

and second page contains

2 6 10

14 18 22

26 30 34

and so on so that when the pages are cut, each stack is sorted. Hope I made myself clear.

Any help is appreciated.

Thanks

Since we have no idea how you have this coded it is hard to say much

Looks like you could track the page number in a variable

Then as you go across/down the page start with the page number for the first one add 4 for the next one add 4 for the next one and so on until the end of the page then repeat for each page

1 1+4=5 5+4=9
9+4=13 ....
...

2 2+4=6 6+4=10
.....

3 3+4=7 ....

Will that work for you?

If not then maybe you should show us some code