Re: [NTG-context] Trouble setting PDF boxes

Hello, I'm happy to report that I got this working after much trawling through the source and documentation. The code below produces a pdf with the MediaBox, CropBox, BleedBox and TrimBox all in the places I specified in my original message. I hope it helps illustrate how to set these PDF boxes using Lua. I would much appreciate any feedback on how the Lua code can be cleaned up or made more flexible (the bleed is hard-coded in because I didn't know how to obtain the user-specified bleedoffset, for example), or made better in any other way. Jack \setuppapersize[A5][A4] \setuplayout[location=middle, marking=on] \setupinteraction [title={TestDoc}, author={Anon}] \setupbackend [format=PDF/X-1a:2003, intent={ISO Coated v2 300\letterpercent\space (ECI)}] \setupinteractionscreen[width=max,height=max] \startluacode moduledata.mystuff={} respecify_pdf_boxes = function() local pdfverbose = lpdf.verbose local factor = number.dimenfactors.bp local f_value = string.formatters["\letterpercent.6N"] local function boxvalue(n) return pdfverbose(f_value(factor * n)) end local paperwidth = tex.dimen.printpaperwidth local paperheight = tex.dimen.printpaperheight local pagewidth = tex.dimen.paperwidth local pageheight = tex.dimen.paperheight local bleedoffset = 3 / number.dimenfactors.mm local pdfarray = lpdf.array lpdf.addtopageattributes("MediaBox", pdfarray { boxvalue(0), boxvalue(0), boxvalue(paperwidth), boxvalue(paperheight),}) lpdf.addtopageattributes("CropBox", pdfarray { boxvalue(0), boxvalue(0), boxvalue(paperwidth), boxvalue(paperheight),}) lpdf.addtopageattributes("TrimBox", pdfarray { boxvalue((paperwidth - pagewidth) / 2), boxvalue((paperheight - pageheight) / 2), boxvalue((paperwidth + pagewidth) / 2), boxvalue((paperheight + pageheight) / 2),}) lpdf.addtopageattributes("BleedBox", pdfarray { boxvalue((paperwidth - pagewidth) / 2 - bleedoffset), boxvalue((paperheight - pageheight) / 2 - bleedoffset), boxvalue((paperwidth + pagewidth) / 2 + bleedoffset), boxvalue((paperheight + pageheight) / 2 + bleedoffset),}) end moduledata.mystuff.respecify_pdf_boxes = respecify_pdf_boxes lpdf.registerpagefinalizer(moduledata.mystuff.respecify_pdf_boxes, "respecify pdf boxes") \stopluacode \starttext test \stoptext On Sun, 26 Apr 2020 at 02:42, Jack Steyn wrote:

After much searching, my probably laughable attempt consists of combining the answer to the question at https://tex.stackexchange.com/questions/433110/setting-page-attributes-of-ev... with what I can see in the source at https://source.contextgarden.net/tex/context/base/mkiv/lpdf-mis.lua:

\appendtoks \startluacode local formatters = string.formatters

local pdfverbose = lpdf.verbose local pdfarray = lpdf.array

local factor = number.dimenfactors.bp local f_value = formatters["\letterpercent.6N"]

local function boxvalue(n) return pdfverbose(f_value(factor * n)) end

lpdf.addtopageattributes("TrimBox", pdfarray { boxvalue(30), boxvalue(30), boxvalue(180), boxvalue(267),}) \stopluacode \to \aftereverypage

This code throws no errors, but unfortunately it also has no effect. What am I doing wrong?

Jack

On Sat, 25 Apr 2020 at 22:37, Jack Steyn wrote:

...

Hi,

I am having trouble setting the PDF boxes to my desired dimensions. Suppose I have \setuppapersize[*a*][*b*]. I want CropBox = MediaBox = *b*. So far, so good: I can just use cropoffset=0mm in \setuplayout. But I want TrimBox = *a*. However, as far as I can see, I can't achieve this using trimoffset in \setuplayout unless (width of *b*) – (width of *a*) = (height of *b*) – (height of *a*), which does not hold in my case. So it looks like I need to find another way to set the TrimBox (and the BleedBox, which I want to be 3mm wider and taller than the TrimBox). Does anyone know how to do this?

Best,

Jack