[xep-support] XEP and italic font-style

I'm using XEP 4.7.

I have a Chinese document where some characters get rendered
in italic, even though I have not registered a font file for
font-style italic. It is my understanding that if XEP encounters
a font-style of italic in FO, but no italic font has been registered
for the active font-family, it would fallback to the normal/roman
typeface.

Is XEP performing an auto-slanting of the font? Does the
TrueType format allow a font to include italic/slant information,
even if the main glyph metrics are normal/roman?

Note, when I explictly register the font-style italic in xep.xml
(using the same file for normal style registration), the italics
disappear. For example:

      <font-family name="zycjkhei">
        <font>
          <font-data name="zycjkhei" ttf="zh_cn/zyhei.ttf" embed="true"/>
        </font>
        <font style="italic">
          <font-data name="zycjkhei" ttf="zh_cn/zyhei.ttf" embed="true"/>
        </font>
      </font-family>
      <font-family name="zycjksun">
        <font>
          <font-data name="zycjksun" ttf="zh_cn/zysong.ttf" embed="true"/>
        </font>
        <font style="italic">
          <font-data name="zycjksun" ttf="zh_cn/zysong.ttf" embed="true"/>
        </font>
      </font-family>
      <font-family name="fzfs">
        <font>
          <font-data name="fzfs" ttf="zh_cn/fzfs.ttf" embed="true"/>
        </font>
        <font style="italic">
          <font-data name="fzfs" ttf="zh_cn/fzfs.ttf" embed="true"/>
        </font>
      </font-family>

When the style="italic" definitions are removed, XEP somehow
manages to italicize text.

--ewh

--
Earl Hood
Software Engineer
ATCL Doctools
earl.hood@hp.com
-------------------
(*) To unsubscribe, send a message with words 'unsubscribe xep-support'
in the body of the message to majordomo@renderx.com from the address
you are subscribed from.
(*) By using the Service, you expressly agree to these Terms of Service http://www.renderx.com/terms-of-service.html