Re: One Page Dungeon Layout in groff?

[Deri]

On Monday, 15 August 2022 11:20:10 BST Ralph Corderoy wrote:
> Second, gropdf(1) chokes on gm PDF with
> 
>     PDF Dict Key 'endstream' does not start with '/'
> 
> so I filter gm's output through ps2pdf(1) first.

I created a random png to pdf with gm convert and it produced a pdf which 
caused the same error message. Running "qdf --check" on the pdf produced 
several messages:-

checking AJ.pdf
PDF Version: 1.2
File is not encrypted
File is not linearized
WARNING: AJ.pdf (object 11 0, offset 10197): unknown token while reading 
object treating as string
WARNING: AJ.pdf (object 11 0, offset 10207): unknown token while reading 
object treating as string
WARNING: AJ.pdf (object 11 0, offset 10219): unknown token while reading 
object treating as string
WARNING: AJ.pdf (object 11 0, offset 10227): unknown token while reading 
object treating as string
WARNING: AJ.pdf (object 11 0, offset 10234): unknown token while reading 
object treating as string
WARNING: AJ.pdf (object 11 0, offset 10261): unknown token while reading 
object treating as string
WARNING: AJ.pdf (object 11 0, offset 10281): unknown token while reading 
object treating as string
WARNING: AJ.pdf (object 11 0, offset 10301): unknown token while reading 
object treating as string
WARNING: AJ.pdf (object 11 0, offset 10321): unknown token while reading 
object treating as string
WARNING: AJ.pdf (object 11 0, offset 10341): unknown token while reading 
object treating as string
WARNING: AJ.pdf (object 11 0, offset 10361): unknown token while reading 
object treating as string
WARNING: AJ.pdf (object 11 0, offset 10361): too many errors; giving up on 
readng object
WARNING: AJ.pdf (object 11 0, offset 10364): expected endobj

So, the problems are with object 11 in the pdf. Here it is:-

11 0 obj
<<

endstream
endobj

It starts a hash with "<<" but fails to close it with ">>". Each hash entry is 
a key/value pair where the key is preceded by a "\". The endstream should 
follow after a stream but that is missing. In fact object 11 is not referenced 
by any other object in the file so could be dropped completely, which is 
probably what ps2pdf has done.

Interestingly if you use the command "convert file.png file.pdf" a valid pdf 
is produced which works with gropdf. It may also give a clue what object 11 
was intended to be. In the valid pdf it is specified as a thumbnail of the 
embedded image, but because it is just a single pixel it does not fulfill its 
role very well!

Laurens Wrote:-

> true, it's quicker, converting the postscript to pdf takes longer then the
> actual formatting. I found the quality of the convert map somewhat lacking
> in the pdf example, though. I'll probably stick to what I've got.

Does the map have to be a png? If it can be produced in a vector format, i.e. 
svg, postscript, or even built using groff draw primitives, it will 
considerably improve the quality of the map and substantially reduce the size 
of the pdf produced.

Cheers 

Deri