[reportlab-users] Reportlab performance

[Robin Becker]

On 17/05/2010 09:27, Andy Robinson wrote:

> On 17 May 2010 08:04, Henning von Bargen<H.vonBargen at t-p.com>  wrote:

>> Another idea that came to my mind:

> ...

>> 3. In the final step of the PDF creation process, when

>>    the /Pages object is written, just put the TOC pages

>>    before the content pages.

>

> This is a good idea.  Very often the cover, TOC and other 'front

> matter' can be printed without visible numbers. Reordering pages at

> the end might not be too hard.

>

> We need an API which allows this to work with Platypus without massive

> changes.   Some way to say "the following pages / story-sections

> eventually belong elsewhere in the document; make them now but flag

> them".  Or perhaps even "reserve some blank pages, jump ahead, then

> compact and remove unused ones at the end".  Then have a final

> 'reshuffle' pass at the end.   Of course the reordering pass needs to

> 'offset' the target page numbers as they will have moved.

>

> How about ActionFlowables called GoTo and GoSub? ;-)

.......

I don't think this is really a platypus specific problem; the canvas code array 
stores all of the pdf operations prior to the final rendering which happens wne 
save is called. I think what really matters is whether those operations contain 
any position dependent values; if not then it should be possible to collect the 
code from the TOC/Front matter pages at the end and then re-inject at the front 
of the actual document. However this requires support from the canvas layer 
rather than platypus since proviing the _code locations can be recorded some 
fairly simple flowables woud do the trick.
-- 
Robin Becker