Aura H2O font size <14 2 panel rendering for pages.

[masterz87]

I have included a scrambled epub that has a lot of stuff cut out mainly all but the first part of the book, and the images contained therein b/c the uploader refuses to work for me for anything more than ~150KiB.

Anyway, I used the kobo patches and kept the font size for the h20(i believe that's the one) at 12pt but when you select that size then you get double rendering as seen in the screenshot. This _only_ happens in some epubs but not all so I can't track down why this is happening and it is driving me insane.


P.S.
If someone knows a way to extract the CSS rules that kobo uses I'd like to know how to replace coolreader as it's epub reader doesn't render books properly(at least how every other e-reader i've used have done it).

[davidfor]

Originally Posted by masterz87

I have included a scrambled epub that has a lot of stuff cut out mainly all but the first part of the book, and the images contained therein b/c the uploader refuses to work for me for anything more than ~150KiB.

Do you mean the uploader to MR? If so, I've never had any problems with the size. Though I don't upload many.

Anyway, I used the kobo patches and kept the font size for the h20(i believe that's the one) at 12pt but when you select that size then you get double rendering as seen in the screenshot. This _only_ happens in some epubs but not all so I can't track down why this is happening and it is driving me insane.

The epub render can change to two column mode when you use the smallest font sizes. That's what this looks like. I don't know the rules for exactly when it happens as I can't use a font that size so very rarely see it. I have tried it on my Glo HD with the smallest font setting, it doesn't trigger the two column mode. It might be different on the larger devices.

P.S.
If someone knows a way to extract the CSS rules that kobo uses I'd like to know how to replace coolreader as it's epub reader doesn't render books properly(at least how every other e-reader i've used have done it).

Kobo actually uses what it in the book. For epubs, I can't think of them overriding anything except when you choose one of the justification options. And the font size and line spacing option will only affect styles that use relative sizes and act in the same way.

The kepub renderer overrides a little more. For example, it ignores widows and orphans settings and uses 1 for both. But, in general, it uses the styles defined in the book.

[GeoffR]

The Adobe ePub reader determines the number of columns to use based on the width of the screen in em units, i.e. the smaller the font, the wider the screen is when measured in em, and so the more columns used.

Changing the body font sizes in the CSS stylesheet and then rescaling all the other font sizes in proportion might affect the calculations, so if the publisher has done this (many do unfortunately) then the final size of the text on the screen where the number of columns change could be different for each book.

However you can quite easily change the underlying threshold font sizes that are used to select the number of columns to use by editing the Adobe XPGT stylesheet (usually called page-template.xpgt if the book has one, or add your own if it doesn't.)

You might also be able to use the XPGT stylesheet to force a particular number of columns to be used, I haven't looked into that.

Attached is a sample ePub that increases the font size thresholds so that I can get two or three columns on my Glo as the font size is reduced. I don't know much about the format of the XPGT stylesheet, I'm just going by what I have seen some publishers do. Adjust the values "55em", "40em", "25em" to set the width that the screen has to be before more columns are used.

page-template.xpgt

Spoiler:

<ade:template xmlns="http://www.w3.org/1999/xhtml"
	      xmlns:ade="http://ns.adobe.com/2006/ade"
	      xmlns:fo="http://www.w3.org/1999/XSL/Format">

  <fo:layout-master-set>

    <fo:simple-page-master master-name="one_column">
      <fo:region-body column-count="1"/>
    </fo:simple-page-master>

    <fo:simple-page-master master-name="two_columns">
      <fo:region-body column-count="2" column-gap="10pt"/>
    </fo:simple-page-master>

    <fo:simple-page-master master-name="three_columns">
      <fo:region-body column-count="3" column-gap="10pt"/>
    </fo:simple-page-master>

    <fo:simple-page-master master-name="four_columns">
      <fo:region-body column-count="4" column-gap="10pt"/>
    </fo:simple-page-master>

    <fo:page-sequence-master>
      <fo:repeatable-page-master-alternatives>
        <fo:conditional-page-master-reference
	    master-reference="four_columns"
	    ade:min-page-width="55em"/>
        <fo:conditional-page-master-reference
	    master-reference="three_columns"
	    ade:min-page-width="40em"/>
        <fo:conditional-page-master-reference
	    master-reference="two_columns"
	    ade:min-page-width="25em"/>
        <fo:conditional-page-master-reference
	    master-reference="one_column"/>
      </fo:repeatable-page-master-alternatives>
    </fo:page-sequence-master>

  </fo:layout-master-set>

</ade:template>

[GeoffR]

Attached is another example ePub that uses two different XPGT stylesheets, one for the cover page that forces single-column layout, and another for the chapters that forces two-column layout, regardless of font size.

There is probably a much simpler way to do this, but I don't know enough about the format of the XPGT stylesheet, I'm just adapting from examples I have seen publishers use.

[masterz87]

that seems to be the issue, I'm _sure_ that the books that do the stupid double column thing are all using the adobe xpgt stylesheet thing. Comparing 3 books that don't have that but still change font size relatively and one that does the xpgt file only that one does the stupid double column thing. Also when it does that the font-size drastically changes they actually go to the font-size that I would've imagined a 13pt font on a screen of the high dpi that the h20 has would look like.

[Quoth]

Multi column was invented to simplify mechanical typesetting and for wider pages (newspapers, magazines). I find it horrible even in books (the Bible is the only common book I can think of set in more than one column and single column versions exist now).
Why do you want it on eBooks? Or is a publisher foisting it on you? Unless the eReader is about 8" minimum and 250dpi or better I can't see it working well. The cheaper 6" ereaders are not big enough and often only about 167 dpi to 200 dpi (?), like fax resolution.

[GeoffR]

Originally Posted by masterz87

that seems to be the issue, I'm _sure_ that the books that do the stupid double column thing are all using the adobe xpgt stylesheet thing. Comparing 3 books that don't have that but still change font size relatively and one that does the xpgt file only that one does the stupid double column thing. Also when it does that the font-size drastically changes they actually go to the font-size that I would've imagined a 13pt font on a screen of the high dpi that the h20 has would look like.

If it is the XPGT stylesheet causing problems, then the Modify ePub plugin for Calibre has an option to remove it and tidy up the links. Although the XPGT stylesheet seems like it could be used to do all sorts of interesting things, I've never seen a publisher do anything useful with it.