[Development] Qt PDF as a new TP module for Qt 5.14

[Lisandro Damián Nicanor Pérez Meyer]

Hi!

On Mon, 12 Aug 2019 at 09:39, Kai Köhne <Kai.Koehne at qt.io> wrote:
[snip]
>
> Qt PDF is so far a Qt labs module [1]. It allows Qt applications to render/view PDF's in QWidget based applications [2], and is built on top of PDFium. However, development has been stagnant, also because it is built on top of a rather old version of PDFium.
>
> Why wasn't PDFium updated? PDFium got merged into Chromium a while ago, and is nowadays built as part of Chromium, using their build system (gn). Updating qtpdf.git to ship with latest PDFium would require quite some work, and keeping it up to date would require continuous work, too - work that nobody was willing to invest into so far.
>
> But it turns out that, since Qt 5.11, we have PDFium already in our sources, and we're actually also building it! It's part of the Qt WebEngine libs that use it for PDF rendering in HTML. So technically, you can already render PDF's by loading them into a Qt WebEngine page. Anyhow, not everybody wants to ship a web browser for 'just' rendering PDF's [3] ...
>

So maintaining it under it's build system it's troublesome, but
letting other people do it in yet another build system is ok. Sorry,
that sounds fishy.

PDF libraries tend to be a common source of CVEs, so whichever library
is used it should be certainly easy to update without the need of a
third party acting as a proxy.