Quote:
Originally Posted by HarryT
Hi Bob,
Thank you for your useful summary.
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Actually the summary did not cover all the cases. A real book has forced page breaks for things like chapter boundaries and widow and orphan rules can change the page break also. In addition images will cause page breaks since the image can't be split very easily. Every time the font is changed, and the cybook lets you pick your own, the entire book page scheme is thrown out the window. Different fonts kern differently so even if you have the same size the same number of words won't fit on a page.
When a book has specialized text like a quote with different margins or a poem embedded in it then the rules change once again.
Not only is pagination computed in the forward direction it has to be computed backwards as well. If you look at a real mobipocket implementation of their reader and walk past a chapter and then back up you will notice that they attempt to keep the partial page intact (which is done by remembering it from when you went forward). If you go to a new chapter and then backup the history isn't there and the partial page is rendered improperly.
Book readers that support real pagination have a limit to fonts and font sizes and then they store every page boundary in a separate database. This effort is best done on a computer before the book is ever downloaded since it is very compute intensive. This removes flexibility like changing font sizes or font families on the fly after the fact.
Dale