Text alignment in generated PDFs (print card from ... to... into...)

[Ben Rubinstein]

I have a stack which generates a PDF report.

Printing is opened using
    	set the printPaperOrientation to "landscape"
       	set the printPaperScale to 0.60
   	open printing to pdf <filename>

Each page is made by filling in various fields, and setting the data for a 
graph widget; then using
	print card from <point> to <point> into <rect>


If I simply use the IDE menus to set page setup to landscape/60%, and Print 
Card to Preview or Save to PDF, it works fine.

But when the PDF is generated by the above code, text in right-aligned fields 
are not aligned neatly, but with a ragged edge. The effect is what I'd expect 
if the text had been measured with one font/size, but displayed with another.


When I started digging, it started to look as though there may be two 
different code paths.

The Dictionary entry for open printing doesn't mention the "... to pdf 
<filename>" syntax. Although not linked from the entry for "open printing", 
the Dictionary does have an entry for the "printerOutput" property, which it 
says can be given a few different values, including

	 file - <filename> : output to the given file. The format of the file depends 
on the platform:

	preview - output to print preview (only supported on Mac OS X).


That's sic: there's nothing after "depends on the platform:" except for the 
next option, "preview".

With printerOutput set to "preview" the document is opened in the mac Preview 
app... and the right-aligned text is indeed right-aligned.

The "file" option works, although the Dictionary entry is unhelpful in 
relation to the syntax: the format needs to be "file:<filename>" (clue found 
in User Guide). Anything else is either an error, or nothing is produced. With 
that format, if the filename ends in .pdf, a PDF is produced, but the document 
is always portrait; if the code specified landscape, the output is squeezed 
(which I take to mean that the printPaperRect lied).

So it seems that, at least on macOS, there are two routes for printing to PDF, 
with exciting variations:

a) open printing to pdf <filename>

This route generates a PDF file on disk; printPaperOrientation and 
printPaperScale are both honoured; but there are text alignment problems.


b) set printerOutput to "preview" ; open printing

This route generates a temporary PDF opened in the Preview app; right aligned 
text is correct; printPaperOrientation is honoured; but printPaperScale is 
ignored.

c) set printerOutput to "file:<filename>" ; open printing

This route generates a PDF file on disk; printPaperOrientation doesn't affect 
the document orientation, but does affect the printPaperRect; printPaperScale 
is ignored. But right-aligned text is fine!


As an extra detail, another undocumented (at least in the Dictionary) feature 
which I evidently discovered somewhere sometime, is that you can use the syntax

	open printing to pdf <filename> with options <array>

to set attributes of the PDF such as Title, Author and so on.

(Attempting to use the syntax
	open printing with options <array>
is an error, however.)

It's all a bit confusing!!

Anyway, this email got longer as I continued to investigate. All I really want 
is to figure out a way to get my nice right-aligned text right. Is it perhaps 
possibly that if I started with a different font or font size, it would render 
the same way in the PDF as it does on screen?

Any tips, lore, suggestions welcome.

Ben