Daisy Wiki PDF Notes

Introduction

Daisy generates PDFs by feeding XSL-FO (a vocabulary for specifying formatting semantics) to Apache FOP (and XSL-FO processor). The PDFs are generated on the fly when a user requests them.

Images

FOP caches images, normally indefinitely. Daisy clears FOPs' image cache from time to time, by default every 5 minutes (this is configurable in the cocoon.xconf file). So if you upload a new version of an image, it can take up to 5 minutes before appearing in the PDF. Closing and reopening your browser would also give immediately the new variant, since images are retrieved on a per-session basis (the sessionid is encoded in the image URL).

Links

In PDF output, link URLs are mentioned in footnotes.

Layout limitations

Below we list the known limitations in PDF output.

Table column widths

FOP can't auto-balance column widths like web browsers do. Therefore, by default all columns in a table are made the same width, which might give undesirable results. However, you can assign custom column widths in the editor through the table settings dialog. Next to the absolute widths such as cm and mm, there's also the special unit * (star). This is for proportional widths. For example, assigning the columns of a two-column table the widths 1* and 2* respectively, will make the first column take one third of the width and the second two thirds.

Another possibilities is to assign a class to the table and use that to perform appropriate styling in a custom skin or document type specific XSLT.

Text flow around images

Text flow around images is not supported.

Table cell vertical alignment

Table cell vertical alignment is not supported.