Is it possible to increase margin on one side?

[hugolundin]

I want to scale a PDF and left-align the original content. Is this possible?

[tavinus]

Hi!
This is not supported at this point but I may try to fit it in.
The scaling sets an offset based on some calculations comparing the base size and target size to center the page. To left-align I guess you would still want some margin on the left size, but a fixed one right? Not sure, but I guess we would need a fixed left margin and then the right margin gets what is left from the paper size. Ideas welcome...

[tavinus]

Ok, so the way it is centered in scaling mode is by setting the Translation X and Y at the scale call which is injected into the new PDF. I am guessing we would need to fix the translation X to some arbitrary postscript-points (we could use mm and inches and transform them if needed as well, since that is already implemented).

However, I am not sure this would work fine in all cases. I will test it to see how it performs.

[tavinus]

Makes me wonder if what you want is just to keep everything in place?
I mean, maybe just removing the translation call could do that, but I am not sure. If that is the case we would need just a flag like --keep-position that would remove the translation from the command.

Or we could add/remove points from the calculated translations (which are based on the scaling factor).

Or we could add a <</PageOffset [-72 0]>> at the setpagedevice call after the scale/translate call. But I am not sure these would work properly together.

Some references:

• https://stackoverflow.com/questions/11153072/resize-a4-pdf-to-sra4-and-center-content
• https://stackoverflow.com/questions/3447720/how-can-i-shift-page-images-in-pdf-files-more-to-the-left-or-to-the-right
• http://www.bobdbob.com/~deneb/doc/ghostscript_margins.html
• https://www-cdf.fnal.gov/offline/PostScript/PLRM2.pdf

[tavinus]

So, would it work for you if the content was kept in place (top-left corner) when scaling?
Or would you actually want to just left-align your pages (without actually scaling it)?
Honestly I am not 100% sure on the top-left, but think it stays there. I think it is either there or bottom-right but I will test it to make sure. This will require a lot of testing, but the problem is that I am not sure I understand what you are trying to do.

[masgo]

Hi, I have a very similar problem: I want to gain whitespace on one side of the paper by shrinking the content. Currently the content is shrunken and centered. So, If I shrink it by 6%, I have 3% whitespace on either side. If it would be possible to push the shrunken content to the border, I would have the 6% space on one side and therefore enough margin for my needs.

[tavinus]

I see.
That may be the better way to do it.
I mean setting percentages for each 4 sides and also offer some presets (top-left for example).
Zero-margin may be too agressive (almost a crop), so a flag for that may also be needed.

I will try to find the time to address this soon.
Cheers!

[tavinus]

Hi!
I have pushed some changes on a new release - v2.2.0

This one makes possible to reposition the PDF:

• Vertical : top/bottom/center
• Horizontal : left/right/center
• xoffset to move horizontally (in points)
• yoffset to move vertically (in points)

Offset makes possible to fine-tune on top of the base positioning.
So you can position at top-left and then fine-tune it with offsetting, for example.

Please let me know if that solves your problem.
The release notes and the --help option explain the new functionality.

Edit 1: v2.2.1 with yet more changes is out!

Edit 2: Please note that GS anchors on bottom-left. It may be a bit weird to adjust the x/y offsets because of that. Play a bit with positive/negative x/y offsets so you can understand how it works and then position the PDF where you want it to be. You can certainly use both vert/hor alignment and x/y offseting together.

Cheers!
Gus

[BryanEllis]

Using the new xtrans/ytrans features I was able to move my page content changing the margins. It is really great.

[hugolundin]

Awesome! I solved this problem using another library, however what you have done seem to solve the original problem. Should I close the issue?

[tavinus]

Cool! Glad to know! 👍
Sorry I could not tackle this before.

v2.3.0 is out BTW

Cheers!
Gus