MobileRead Forums - View Single Post - Custom Font -- Where to Map Glyphs, How to Display Characters?

GrannyGrump · 03-03-2014, 02:44 AM

Mods-- I wasn't sure whether to post this in Epub or in Workshop, please move me if needed.

I am assembling a custom font with fleurons and dividers, using freeware TypeLight (I would like to do a mini-tutorial later if I can get this question figured out.)

I remember Jellby remarking on another thread about fonts, that under epub specs, special symbols/glyphs must NOT be mapped to normal characters, and should be assigned to the "Private Use" unicode block. (Remember the thread about the Apple symbol? https://www.mobileread.com/forums/sho...d.php?t=222825
and the one about Old English Blackletter font?
https://www.mobileread.com/forums/sho...d.php?t=224276

BUT --- Apparently there is no way to call up Private Use characters in epub using the usual number entity or named entity code.

In my test epub, to be sure it wasn't a problem with my custom font, I embedded Wingdings font and also Quivira (a redistributable font with wide unicode coverage).

I checked to be sure that each one had a character existing at code point F021 in the Private Use block. I try to call the character using either/both &_#_xf021; or &_#_61473; [assume the underscores are not used, they are here to keep the forum from converting to actual characters].

Sigil, ADE, and Calibre Reader all show a missing character glyph.

Sigil and Calibre DO show the trigram character from code point 2630 in the "Dingbats" Area, but ADE does not, even though I have fonts correctly embedded. I am thinking this is something to do with insufficient Unicode support on the part of ADE.

So it would seem that there is no way to call up these characters programatically. The unicode.org site http://www.unicode.org/charts/#symbols says re: Private Use Area: "The Private Use Area does not contain any character assignments, consequently no character code charts or names lists are provided for this area."

HOWEVER --- if I map the glyphs in the Latin 1 or Latin Extended areas (for example, to tilde, bullet, underscore, etc ), all three softwares show the characters correctly.
So my wish is to map the glyphs to seldom-used Latin characters (or maybe Greek, Cyrillic, whatever would work) in order to get them to display correctly.

Will the Epub Spec Police come knocking at my door? Is there any other alternative that will work?

03-03-2014, 02:44 AM	#1
GrannyGrump Obsessively Dedicated... Posts: 3,221 Karma: 35037583 Join Date: May 2011 Location: PA {back in the usa!} Device: Sony PRS-T2, ADE on PC	Custom Font -- Where to Map Glyphs, How to Display Characters? Mods-- I wasn't sure whether to post this in Epub or in Workshop, please move me if needed. I am assembling a custom font with fleurons and dividers, using freeware TypeLight (I would like to do a mini-tutorial later if I can get this question figured out.) I remember Jellby remarking on another thread about fonts, that under epub specs, special symbols/glyphs must NOT be mapped to normal characters, and should be assigned to the "Private Use" unicode block. (Remember the thread about the Apple symbol? https://www.mobileread.com/forums/sho...d.php?t=222825 and the one about Old English Blackletter font? https://www.mobileread.com/forums/sho...d.php?t=224276 BUT --- Apparently there is no way to call up Private Use characters in epub using the usual number entity or named entity code. In my test epub, to be sure it wasn't a problem with my custom font, I embedded Wingdings font and also Quivira (a redistributable font with wide unicode coverage). I checked to be sure that each one had a character existing at code point F021 in the Private Use block. I try to call the character using either/both &_#_xf021; or &_#_61473; [assume the underscores are not used, they are here to keep the forum from converting to actual characters]. Sigil, ADE, and Calibre Reader all show a missing character glyph. Sigil and Calibre DO show the trigram character from code point 2630 in the "Dingbats" Area, but ADE does not, even though I have fonts correctly embedded. I am thinking this is something to do with insufficient Unicode support on the part of ADE. So it would seem that there is no way to call up these characters programatically. The unicode.org site http://www.unicode.org/charts/#symbols says re: Private Use Area: "The Private Use Area does not contain any character assignments, consequently no character code charts or names lists are provided for this area." HOWEVER --- if I map the glyphs in the Latin 1 or Latin Extended areas (for example, to tilde, bullet, underscore, etc ), all three softwares show the characters correctly. So my wish is to map the glyphs to seldom-used Latin characters (or maybe Greek, Cyrillic, whatever would work) in order to get them to display correctly. Will the Epub Spec Police come knocking at my door? Is there any other alternative that will work? Last edited by GrannyGrump; 03-03-2014 at 02:56 AM.