I noticed that Journey to the West got slower and slower to read in Adobe Digital Editions. I found out why, and fixed it. Here are the download links again:
Download:
Journey to the West Downloads
License: Creative Commons Attribution-NonCommercial 2.5
Attribution: Based from work copyrighted 2005 by Silk Pagoda (also CC Attribution Non-Commercial 2.5 Licensed).
The reason Adobe Digtial Editions was slow on the ePub version is based on the structure of ePub versus the structure of Mobipocket.
Say that all of my book’s content is in one HTML file. When I stick that into ePub, it’s still just one HTML file. Adobe Digital Editions—and really, just about any ePub reader—unzips and puts the entire file into memory.
That’s fine if the file is, say, the size of a 50 page story. But for a story that’s over 1200 pages long, that method is going to run into problems.
Solution: break up the huge HTML file into 100 much smaller files—one for each chapter.
Now as you go through the book, Adobe Digital Editions will only have perhaps a few small chapters in memory—the ones immediately before and after your position in the overall book. ((Or Adobe Digital Editions is dumber than I think it is, and only has the current chapter in memory. Still, it’s better than having all 100 loaded.)) This speeds everything up considerably. And thus you can read as quickly at Chapter 1 as you can at Chapter 100.
Why didn’t this problem affect the Mobipocket version? Because the mobigen compiler automatically does what I had to do for the ePub—it automatically broke up the longer book into 100 separate files ((100 separate records in its internals, which is actually a Palm database.)), and thus the reader never had more than a few chapters loaded at a time.
And this is where I say Computer Science! and drop off for a good night’s rest.
Spontaneous ∂erivation 
There’s still several ways that you could improve the ePub:
– avoid the inline ToC: the NCX is enough
– use indenting in your CSS for the paragraphs
– add margins on the CSS @page property for DE, or else it might display the page number OVER your text
– add a cover (that’s tricky since there’s no real best practices concerning covers)
– blockquotes for poems and songs ?
Hi Hadrien,
Edit: I moved the comments here, because I believe you were referring to this post. If not, let me know and I’ll move the comments to the correct one. :)
As for the suggestions,
– I left in an inline ToC mostly for the generation of a Mobipocket. I know that you don’t need it for straight ePub—but at the same time, it’s odd to rely on the side panel for chapters with long subtitles, as in Journey to the West.
– Why should I add indenting? Surely an ebook reader takes care of that—which is the case for Mobipocket, the Kindle, calibre, FBReader, Stanza. I’m not going to override the user’s wishes.
– I’ll add margins for Digital Editions.
– I didn’t really want to add a cover image, because finding decent cover art is difficult.
– Blockquotes shift inwards too much for the poems/verses, which are anyways an integral part of the text. I’ve settled for them being separated.
– DE display them in a side panel but they could be displayed in all sort of ways. I agree that it’s more convenient if you’re using the same source for Mobipocket but I really consider that it makes more sense for a ToC to be part of the metadata of a book, rather than its content (and browsing through several pages of ToC at the beginning of a book can be annoying too)
– I agree that this should be taken care of by the reading system, unfortunately, DE doesn’t allow you to set this, which means that for this ePub in DE there’s no indenting at all. I’d like to see a set of best practices concerning fonts, margins, indenting etc. I believe that it’s possible to have both a layout recommended by the publisher and custom user settings if we define a set of rules concerning CSS.
– Same problem here, we shouldn’t have to add margins for DE but unfortunately, they decided to display the page number in the flow.
– I agree, although there’s many ressources for this and for Journey to the West, there’s probably an old cover or various illustrations that are in the public domain.
– I’ll probably create a specific environment in Feedbooks for poems/verses since they require specific CSS properties.
– About the ToC at the beginning; that’s what the “Text” guide does in Mobipocket—it’s where the reader starts reading, and is usually set to skip over the ToC. (And yes, I do wonder why Adobe decided to ditch even the basic guides like this.)
– It would be nice to have user-overrides possible at large. Right now it’s “publisher wins” with regards to specific CSS, and not so much user override.
– Agree about the margins.
– I’ll think about the cover, then. I know there’s one evocative image… but I might have to compose a cover if an intact one doesn’t exist as a scan on the web.
– Something special for poems/verses would be nice.