It's an interesting idea. However, I suspect this will probably not be
necessary. We should be able to make the breaker clever enough to handle
this particular case. ATM, I don't have free brain capacity to dive into
this (even though this is an important and long-awaited feature) but it
may make sense to gather ideas and notes from the mailing list archives
and put these on a Wiki page. I remember that several approaches have
been discussed in the past even though they haven't had anything to do
with our current breaking approach.

On 23.09.2005 20:28:14 Andreas L Delmelle wrote:
> Hi,
> 
> (Apologies for the many posts... I'm definitely on a roll :-))
> 
> Now that it has been made clear to me that the layout-engine first 
> calculates *all* break-possibilities, IMO this also seems to make 
> implementing page-position="last" much, much easier.
> 
> Assuming that no areas are generated until the full element list is 
> known, I'm thinking once you have created the Knuth-element list, 
> instead of starting at element index zero to generate the areas, it 
> would also be possible to have the algorithm start at the last element 
> in the list until we reach the first break-possibility that would make 
> the content exceed the height page-master whose page-position is 
> "last", no?
> At the very least, it would enable us to mark the break-possibility at 
> which the algorithm should consider the last page-master... Obviously, 
> we can't complete the full iteration in that direction, or we would run 
> into problems determining the difference between odd and even, but it 
> seems possible to iterate backwards once and assign a sort of 
> 'favorability degree' to each of break-possibilities --increase or 
> decrease penalty values?--, taking into account that the last page 
> *has* to start somewhere after the marked one --before is impossible, 
> since it won't fit. The generated last page can be thrown away (or 
> serialized to be re-used if the marked possibility just happens to 
> coincide with the actual last page-break).
> 
> Am I getting this correctly?


Jeremias Maerki

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