- From: Lofton Henderson <lofton@rockynet.com>
- Date: Tue, 16 Dec 2008 11:31:08 -0700
- To: WebCGM WG <public-webcgm-wg@w3.org>
Hi WebCGM WG -- This is one of a series about the six I18N comments. Although I18N sent a separate message for each of their comments -- which is how we should reply to I18N -- all comments are conveniently found in a single table [1]. All comments apply to 9.3.2.2, the ACI mapList element [2] [1] http://www.w3.org/International/reviews/0811-webcgm/ [2] http://www.w3.org/TR/2008/WD-webcgm21-20080917/WebCGM21-Config.html#ACI-maplist In this message, I have proposed a response. I have one omission/uncertainty about the specific issue. Email discussion welcome. We will resolve definitely in a WG teleconference. Comment #6 pertains to using a "unicode normalization form" to compare the font names in the metafile with the 'cgmFont' value. It is labelled Substantive by I18N. Comment #6 ===== "Normalization for string comparison should include conversion to a Unicode normalization form, to eliminate issues related to precomposed vs. decomposed characters and issues related to ordering of multiple combining characters." Proposed response: ---------- WebCGM agrees that this is the consistent and reliable way to perform such comparisons. Text to this effect will be added to the description of the 'cgmFont' value -- conversion to unicode normalization form should precede the comparison and follow the other WebCGM-specific normalizations. Add a new sentence to the end of the 'cgmFont' description. "Correct and consistent results when comparing metafile font names with the 'cgmFont' value -- for font names outside of WebCGM's restricted @@core set of thirteen specific fonts@@ [@@link to section 6.5, T.16.13@@] -- require that WebCGM processors convert to a @@unicode normalization form@@ [@@link to the right place in I18N spec "Character Model for the World Wide Web@@] before performing the comparison. This should happen after the WebCGM-specific normalizations." Altogether now, the changes proposed for I18N-5 and I18N-6 would change the 'cgmFont' description: Change 'cgmFont' paragraph from: "The name of the font in the metafile for which font substitution is requested. Before attempting to match a font used in the metafile to the string cgmFont, the both font names are normalized by: converting to lower-case; and stripping out all whitespace, UNDERSCORE, and HYPHEN characters. Note: These normalization rules are applicable for font names specified using the characters of ISOLatin1. They will likely be inapplicable for font names specified using other non-Latin characters." to: "The name of the font in the metafile for which font substitution is requested. Before attempting to match a font used in the metafile to the string cgmFont, both font names are normalized by a WebCGM-specific normalization: converting to lower-case; and stripping out all whitespace, UNDERSCORE, and HYPHEN characters. Note: This WebCGM-specific normalization is derived from and intended for the substantial volume of existing metafiles that aim to invoke fonts from WebCGM's restricted core set of thirteen specific fonts (see @@section 6.5, T.16.13@@). Many such metafiles contain well-known and trivial deviations in the construction of those font names, and they are most often are encoded in WebCGM's default character encoding of ISO 8859-1. The rules may be less useful outside of this intended scope of normalization. After this WebCGM-specific normalization, correct and consistent results when comparing metafile font names with the 'cgmFont' value -- for font names outside of WebCGM's restricted @@core set of thirteen specific fonts@@ [@@link to section 6.5, T.16.13@@] -- may require that WebCGM processors convert to a @@unicode normalization form@@ [@@link to the right place in I18N spec "Character Model for the World Wide Web@@] before performing the comparison." INCOMPLETE: We don't yet have a reply from I18N to our question about whether we should recommend a specific one of the four normalization forms. Maybe it doesn't matter, i.e., any one of the 4 forms would work equally well? Regards, -Lofton.
Received on Tuesday, 16 December 2008 18:36:25 UTC