Add help text for paper size of PDF output

[danielhjames]

Useful to know if you live in a country which uses A4 paper :-)

[vilcans]

It's a good idea to support A4. Have you tested this so that the layout and margins are correct, and text never overflows in A4 format?

Regarding the pull request, I think changing the page size shouldn't require code changes. I'll make sure to make it configurable instead.

[danielhjames]

Hi @vilcans I did test it with my own screenplay of 59 pages, looks good to me in A4!

A command-line option to change paper size at runtime would be neat. I see there are a bunch of other settings in export/pdf.py but the screenplay use case is not like a general PDF renderer, where any style is desirable.

[vilcans]

I made a branch with support for specifying paper size, and the result is that there's a large top margin on screenplays in A4 format. Probably because the number of lines is hardcoded for the letter size. I'll look into it more.

[danielhjames]

Hi @vilcans in another project I have controlled the style of PDF outputs using the CSS Paged Media specification, similar to export/default.css in screenplain:

https://www.w3.org/TR/css-page-3/

This allows very precise control, but I don't see any support for this Paged Media specification in ReportLab. Also, the screenplain use case is limited to a single format and a small number of paper sizes. Therefore hard coding the parameters for each supported paper size could be the simplest solution.