Abstract
This document describes and prioritises gaps for the support of languages using the Gujarati script on the Web and in eBooks. In particular, it is concerned with text layout. It checks that needed features are supported in W3C specifications, in particular HTML and CSS and those relating to digital publications. It also checks whether the features have been implemented in browsers and ereaders. This is a preliminary analysis.
Status of This Document
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document at the time of its publication. Other documents may supersede
this document. A list of current W3C publications and the latest revision
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This document describes and prioritises gaps for the support of languages using the Gujarati script on the Web and in eBooks. In particular, it is concerned with text layout. It checks that needed features are supported in W3C specifications, in particular HTML and CSS and those relating to digital publications. It also checks whether the features have been implemented in browsers and ereaders. This document
linked to from the language matrix that tracks Web support for many languages.
The editor's draft of this document is being developed by the India International Program Layout Task Force, part of the W3C Internationalization Interest Group. It is published by the Internationalization Working Group. The end target for this document is a Working Group Note.
This document was published by the Internationalization Working Group as a
Working Draft.
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discussion of this specification.
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by the W3C Membership.
This is a draft document and may be updated, replaced
or obsoleted by other documents at any time. It is inappropriate to cite this
document as other than work in progress.
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operating under the
1 August 2017 W3C Patent
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15 September 2020 W3C Process Document.
1. Introduction
The W3C needs to make sure that the needs of scripts and languages around the world are built in to technologies such as HTML, CSS, SVG, etc. so that Web pages and eBooks can look and behave as people expect around the world.
This page documents difficulties people encounter when trying to use the Gujarati language in the Gujarati script on the Web.
Having identified an issue, it investigates the current status with regards to web specifications and implementations by user agents (browsers, e-readers, etc.), and attempts to prioritise the severity of the issue for web users.
A summary of this report and others can be found as part of the language matrix.
For a description of the Gujarati script see the (non-W3C) page Gujarati, which summarises aspects of the orthography and typographic features, including relevant Unicode characters and their use.
1.1 Work flow
This version of the document is a preliminary analysis
Gap analysis work usually starts with a preliminary analysis, conducted quickly by one or a small group of experts. Then a more detailed analysis is carried out, involving a wider range of experts. The detailed analysis may involve the development of tests, in order to illustrate issues and track results for browsers. The next phase is ongoing maintenance. It is expected that the resulting document will not be frozen: as gaps are fixed, this should be noted in the document. It is also possible that new gaps are noticed or arise, and they can be added to this document when that happens.
1.2 Prioritization
This document not only describes gaps, it also attempts to prioritise them in terms of the impact on the local user. The prioritisation is indicated by colour.
Key:
It is important to note that these colours do not indicate to what extent a particular features is broken. They indicate the impact of a broken or missing feature on the content author or end user.
Basic styling is the level that would be generally accepted as sufficient for most Web pages. Advanced level support would include additional features one might expect to include in ebooks or other advanced typographic formats. There may be features of a script or language that are not supported on the Web, but that are not generally regarded as necessary (usually archaic or obscure features). In this case, the feature can be described here, but the status should be marked as OK.
The decision as to what priority level is assigned to a described gap is down to the experts doing the gap analysis. It may not always be straightforward to decide. If a given section in this document refers to more than one feature that is broken, each with different impacts on Web users, the priority for the section should be the lowest denominator.
A cell can be scored as OK if the feature in question is specified in an appropriate specification, and is supported by user agents. A specification that is in CR or later and has two implementations in 'major' browsers will count. This means that the feature may not be supported in all browsers yet. (At some point in the future we may try to distinguish, visually, whether support is available in a specification but still pending in major browsers or applications.)
3. Characters and phrases
3.3 Font styles, weight, etc
This covers ways of modifying the glyphs, such as for italicisation, bolding, oblique, etc. Do italic fonts lean in the right direction? Is synthesised italicisation problematic? Are there other problems relating to bolding or italicisation - perhaps relating to generalised assumptions of applicability? See available information or check for currently needed data.
3.4 Glyph shaping and positioning
Does the script in question require additional user control features to support alterations to the position or shape of glyphs, for example adjusting the distance between the base text and diacritics, or changing the glyphs used in a systematic way? Do you need to be able to compose/decompose conjuncts, or show characters that are otherwise hidden, etc? See available information or check for currently needed data.
3.5 Cursive text
If this script is cursive (eg. Arabic, N’Ko, Syriac, etc), are there problems or needed features related to the handling of cursive text? Do cursive links break if parts of a word are marked up or styled? Do Unicode joiner and non-joiner characters behave as expected? See available information or check for currently needed data.
3.6 Baselines, line-height, etc
Does the browser support requirements for baseline alignment between mixed scripts and in general? See available information or check for currently needed data.
#103 Differences in physical size for fonts affects baseline alignment
By and large, Indian scripts in browsers are rendered with default fonts provided by back-end Operating Systems. If there are major differences in physical size for a particular font size, which most of the times are, it shows the mixed-script text in an un-organized way. This obviously affects all the base-line attributes.
3.8 Grapheme/word segmentation & selection
This is about how text is divided into graphemes, words, sentences, etc., and behaviour associated with that. Do Unicode grapheme clusters appropriately segment character units for your script? When you double- or triple-click on the text, is the expected range of characters highlighted? When you move through the text with the cursor, or backspace, etc. do you see the expected behaviour? (Some of the answers to these questions may be picker up in other sections, such as line-breaking, or initial-letter styling.) See available information or check for currently needed data.
#106 Spans around partial orthographic syllables can't be styled
If you put a span around the ન્ડ two characters of the 3-character syllable ન્ડિ in ઇન્ડિય (eg. in order to color or otherwise style it), the i vowel-sign no longer appears at the start of the word, but looks like it modifies the next character (ય).
Apparently this requirement is a bit difficult to cater to as it requires the knowledge to be transferred by the font to the rendering engine about which part of the glyph is attributed to which code-point in storage. However, if it can be achieved, nothing like it.
#105 Dandas are wrapped alone to the beginning of a line
Gujarati uses full stop to represent the end of the sentence. However if the user wants to use the danda or double danda, as per to Unicode recommendation, they have to come from Devanagari block of Unicode. Devanagari phrase separator । U+0964 DEVANAGARI DANDA or ॥ U+0965 DEVANAGARI DOUBLE DANDA are encoded in the DEVANAGARI block with the intent that they should be used as common punctuation for all the major scripts of India including Gujarati.
The properties of purna viram and deergh viram should be the same as the properties of FullStop or other punctuation marks, and a new line should not begin with purna viram and deergh viram.
#104 Grapheme clusters fail to represent syllabic conjuncts
The Unicode concept of 'grapheme cluster' currently fails to represent syllabic conjuncts (plus vowels, etc) in scripts like Gujarati. This means that various editing operations, line breaking algorithms, vertical text, etc. are likely to break text at the wrong point.
Indic Layout Requirements provides a grammar for indian orthographic syllable boundaries which works for Gujarati, and CSS uses the concept of 'typographic character unit', rather than grapheme cluster, in its specs with the explanation that these cases are beyond the scope of the grapheme cluster concept and that implementations should provide appropriate support. In addition, a modification to the concept of grapheme cluster is currently in development at the Unicode Consortium, which is likely to resolve the problem for a script like Gujarati.
See requirements at: Indic Layout Requirements
3.9 Inline features & punctuation
Are there specific problems related to punctuation or the interaction of the text with punctuation (for example separation of punctuation from previous text, but allowing no line break between)? Are there issues related to handling of abbreviation, ellipsis, or iteration? Are there problems related to bracketing information or demarcating things such as proper nouns, etc? See available information or check for currently needed data.
3.10 Text decoration
This is about ways of marking text (see also specific sections dedicated to quotations and inline notes/annotations). Is it possible to express emphasis or highlight content as expected? Bold, italic and under-/over-lines are not always appropriate, and some scripts have their own unique ways of doing things, that are not in the Western tradition at all. Text delimiters mark certain items or sections off from the main text, such as book names in Chinese, quotations, head markers in Tibetan, etc, and often involve the use of punctuation. Is there any behaviour that isn't well supported, such as overlines for numeric digits in Syriac? Are there issues about the positioning or use of underlines? Some aspects related to the drawing of lines alongside or through text involve local typographic considerations. Do underlines need to be broken in special ways for this script? Do you need support for additional line shapes or widths? Does the distance or position of the lines relative to the text need to vary in ways that are not achievable? Are lines correctly drawn relative to vertical text? See available information or check for currently needed data.
#107 Underline and overline need to clear glyph ascenders and descenders
Indian language text has some signs called as Matras which sometimes join above the shirorekha or below the normal baseline.
Applications should ensure that the underline and overline when getting rendered, should adaquetly be taken into consideration. Chrome browser seemed to be perfectly rendering the underline and overline feature by breaking the same where a matra occurs. Internet Explorer also handles it a bit differently by appropriately lowering or heightening the respective lines.
3.12 Inline notes & annotations
The ruby spec currently specifies an initial subset of requirements for fine-tuning the typography of phonetic and semantic annotations of East Asian text, including furigana, pinyin and zhuyin fuhao systems. Is is adequate for what it sets out to do? What other controls will be needed in the future? What about other types of inline annotation, such as warichu? (For referent-type notes such as footnotes, see below.) See available information or check for currently needed data.
4. Lines and Paragraphs
4.1 Line breaking
Does the browser capture the rules about the way text in your script wraps when it hits the end of a line? Does line-breaking wrap whole 'words' at a time, or characters, or something else (such as syllables in Tibetan and Javanese)? What characters should not appear at the end or start of a line, and what should be done to prevent that? See available information or check for currently needed data.
See also hyphenation below.
4.2 Hyphenation
Is hyphenation used for your script, or something else? If hyphenation is used, does it work as expected? (Note, this is about line-end hyphenation when text is wrapped, rather than use of the hyphen and related characters as punctuation marks.) See available information or check for currently needed data.
4.3 Text alignment & justification
When text in a paragraph needs to have flush lines down both sides, does it follow the rules for your script? Does the script need assistance to conform to a grid pattern? Does your script allow punctuation to hang outside the text box at the start or end of a line? Where adjustments are need to make a line flush, how is that done? Do you shrink/stretch space between words and/or letters? Are word baselines stretched, as in Arabic? What about paragraph indents, or the need for logical alignment keywords, such as start/end, rather than left/right? See available information or check for currently needed data.
4.4 Letter spacing
Some scripts create emphasis or other effects by spacing out the words, letters or syllables in a word. Are there requirements for this script/language that are unsupported? (For justification related spacing, see below.) See available information or check for currently needed data.
#109 Text units for letter-spacing are incorrect
Gujarati is an alphasyllabary and the heart of the writing system is the Akshar. It is very common in the gujarati script to represent/brake words based on Akshara, which is instinctively recognized by users of the script. The same requirement is given here.
As the W3C specification points to Unicode Text Segmentation (TR 29), it is observed that some of the browsers support it (e.g. Chrome and Firefox) whereas Microsoft Edge and Interner Explorer seems to break the words in individual characters.
Also, in cases where there is wrong Akshara formation e.g. Consonant+Matra+Matra, the breaking seems to stack ill formed akshara into one set instead of clearly breaking it separate. This breaking behaviour needs to improve.
There are currently no mechanisms for syllable spacing in HTML/CSS.
4.5 Lists, counters, etc.
The CSS Counter Styles specification describes a limited set of simple and complex styles for counters to be used in list numbering, chapter heading numbering, etc.The rules plus more counter styles (totalling around 120 for over 30 scripts) are listed in the document Ready-made Counter Styles. Do these cover your needs? Are the details correct? Are there other aspects related to counters and lists that need to be addressed? See available information or check for currently needed data.
4.6 Styling initials
Does the browser or ereader correctly handle special styling of the initial letter of a line or paragraph, such as for drop caps or similar? How about the size relationship between the large letter and the lines alongide? where does the large letter anchor relative to the lines alongside? is it normal to include initial quote marks in the large letter? is the large letter really a syllable? etc. Are all of these things working as expected? See available information or check for currently needed data.
#111 Incorrect segmentation for styling initials
Because of the problems associated with grapheme cluster boundaries (see above), first-letter selection in CSS doesn't work well for conjuncts. For example, chrome fails to style the whole conjunct in પ્રૌદ્યોગીકી when using ::first-letter in a selector, and styles only the પ્ instead of પ્રૌ. Similar is the case of Internet Explorer, it only styles પ. This is problematic for many words in a script such as Gujarati, and forces the content author to use explicit spans rather than the proper mechanism for selecting initial letter.
Indian Layout Requirements provides a grammar for indian orthographic syllable boundaries which works for Gujarati, and CSS uses the concept of 'typographic character unit', rather than grapheme cluster, in its specs with the explanation that these cases are beyond the scope of the grapheme cluster concept and that implementations should provide appropriate support. In addition, a modification to the concept of grapheme cluster is currently in development at the Unicode Consortium, which is likely to resolve the problem for a script like Gujarati.
In addition, the alignment of styled initial-letter character glyphs with the rest of the text is not clearly specified or implemented.
See requirements at: Indic Layout Requirements
5. Page & book layout
5.1 General page layout & progression
How are the main text area and ancilliary areas positioned and defined? Are there any special requirements here, such as dimensions in characters for the Japanese kihon hanmen? The book cover for scripts that are read right-to-left scripts is on the right of the spine, rather than the left. Is that provided for? When content can flow vertically and to the left or right, how do you specify the location of objects, text, etc. relative to the flow? For example, keywords 'left' and 'right' are likely to need to be reversed for pages written in English and page written in Arabic. Do tables and grid layouts work as expected? How do columns work in vertical text? Can you mix block of vertical and horizontal text correctly? Does text scroll in the expected direction? Other topics that belong here include any local requirements for things such as printer marks, tables of contents and indexes. See available information or check for currently needed data.