Bug 690781

Summary:	UserUnit not supported by PDF Writer
Product:	Ghostscript	Reporter:	artifex
Component:	PDF Writer	Assignee:	Ken Sharp <ken.sharp>
Status:	NOTIFIED WONTFIX
Severity:	enhancement	CC:	mlungu777
Priority:	P2
Version:	8.64
Hardware:	PC
OS:	Windows XP
Customer:	870	Word Size:	---
Attachments:	ps_XXL_l.ps

Description artifex 2009-09-24 03:18:27 UTC

Very large Postscript files ( e.g. 10x2 meter ) can be converted by Ghostscript.
But when PDF is generated, no UserUnit is used. So the generated PDF can not be
viewed by the Acrobat Reader, which limits the size ( 200 inch ) of PDF files,
when no UserUnit is specified.
It would be an enhancement, if UserUnit would be used when the MediaSize exceeds
200 inch.

Comment 1 artifex 2009-09-24 03:19:55 UTC

Created attachment 5398 [details]
ps_XXL_l.ps

example for a large Postscript file with 10x2 meter

Comment 2 Ray Johnston 2009-09-24 09:41:55 UTC

Does setting the resolution manually to a value less than -r720 (the default)
allow a viewable PDF to be generated?

I thought we automatically set the resolution down when the MediaBox was large,
but I am going from memory, nothaving checked.

Comment 3 Ken Sharp 2009-09-25 05:25:49 UTC

> Does setting the resolution manually to a value less than -r720 (the default)
> allow a viewable PDF to be generated?

No. The problem is that Acrobat has an implementation limit (this is an
*Acrobat* limit, not PDF) of 14,400 units in any dimension for page sizes. Hence
200 inches because the standard unit is 1/72 inch. The user unit is a kludge to
allow larger media sizes, by defining the user unit to be something other than
1/72 inch. (Of course the accuracy of placement potentially suffers)

Why Adobe found it easier to introduce the user unit rather than increase the
maximum media size I have no idea.

The implications for us are massive; every size, position or matrix operation,
as well as any objects referenced from the page with their own matrix (such as
forms or patterns) would have to be rescaled to take account of the current user
unit. Its a lot of work, and would undoubtedly introduce many regressions. Also
its not supported below PDF 1.6 and we nominally produce PDF 1.4.

I'm happy to leave it as an enhancement request, but don't plan on tackling it
any time soon.

Comment 4 Ken Sharp 2011-01-13 08:17:31 UTC

*** Bug 691879 has been marked as a duplicate of this bug. ***

Comment 5 Marcos H. Woehrmann 2012-05-01 10:21:52 UTC

Won't fix, see Comment 3.