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<!DOCTYPE html>
<html lang="en">
<head>
<title>Indic Layout Requirements</title>
<meta charset="utf-8"/>
<script src="https://www.w3.org/Tools/respec/respec-w3c-common" async class="remove"></script>
<script class="remove">
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shortName: "ilreq",
copyrightStart: "2014",
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editors: [
{ name: "Swaran Lata", mailto: "[email protected]", company: "DeitY", w3cid: 39008 },
{ name: "Somnath Chandra", mailto: "[email protected]", company: "DeitY" },
{ name: "Prashant Verma", mailto: "[email protected]", company: "Web Standardization Initiative, DeitY" },
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href: "http:https://cldr.unicode.org",
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title: "Unicode Technical note#10 : South Asian Scripts",
href: "http:https://www.unicode.org/notes/tn10/",
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"UAX29": {
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title: "Draft-Scrip-Grammer Devanagari",
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<link rel="stylesheet" href="local.css" type="text/css" />
</head>
<body>
<div id="abstract">
<p>This document describes the basic requirements for Indic script layout and text support on the Web and in Digital Publications. These requirements provide information for Web technologies such as CSS, HTML, and SVG about how to support users of Indic scripts. The current document focuses on Devanagari, but there are plans to widen the scope to encompass additional Indian scripts as time goes on.</p>
</div>
<div id="sotd">
<p>This document describes the basic requirements for Indic script layout and text support on the Web and in eBooks. These requirements provide information for Web technologies such as CSS, HTML and SVG about how to support users of Indic scripts. The current document focuses on Devanagari, but there are plans to widen the scope to encompass additional Indian scripts as time goes on. </p>
<p>The editor's draft of this document is being developed by the <a href="https://www.w3.org/International/groups/indic-layout/">Indic Layout Task Force</a>, part of the W3C <a href="https://www.w3.org/International/ig/">Internationalization Interest Group</a>. It is published by the <a href="https://www.w3.org/International/core/">Internationalization Working Group</a>. The end target for this document is a Working Group Note.</p>
<div class="note">
<p data-lang="en" style="font-weight: bold; font-size: 120%">Sending comments on this document</p>
<p data-lang="en">If you wish to make comments regarding this document, please raise them as <a href="https://github.com/w3c/ilreq/issues" style="font-size: 120%;">github issues</a>. Only send comments by email if you are unable to raise issues on github (see links below). All comments are welcome.</p>
<p data-lang="en">To make it easier to track comments, please raise separate issues or emails for each comment, and point to the section you are commenting on using a URL for the dated version of the document.</p>
</div>
</div>
<section id="h_introduction">
<h2>Introduction</h2>
<section id="h_about_this_document">
<h2>About this document</h2>
<p>This document describes the basic requirements for Indian Languages layout for display purpose. It discusses some of the major layout requirements in first letter pseudo-element, vertical arrangements of characters, letter spacing, text segmentation, line breaking rules in Indic languages.</p>
<p>The current document focuses on Devanagari, but there are plans to widen the scope to encompass additional Indian scripts as time goes on.</p>
<p>The minimal requirements presented in this document for Indian languages text layout will also be used in E-publishing and CSS standards. This documents covers major issues of e-content in Indian languages in order to create a standard format of text layout to address storage, rendering problems, vertical writing, letter spacing, line breaking etc.</p>
<p>It also describes a set of <abbr title="Augmented Backus–Naur Form">ABNF</abbr>-based rules for valid segmentation of Indic orthographic syllables in order to get the proper display in browsers. Text segmentation[[!UAX29]] and line breaking [[!UAX14]] algorithms are considered in detail. Standards for CSS and digital publications will benefit from this document.</p>
</section>
<section id="h_indian_language_complexities">
<h2>Indian language complexities</h2>
<p> India has large linguistic diversity with 22 constitutionally recognized languages and 12 scripts.This document is currently focused largely on the Devanagari script. The expectation is that over time its scope will widen to cover additional major scripts from the list below.</p>
<p>The mapping between languages and scripts is complex. Multiple languages may have common scripts, while a language can be written in multiple scripts. Each language and script is unique in nature and cannot be easily replicated, even if they share common characteristics. The orthographic changes may also occur in some languages and adoption of new orthography is a gradual process, thus posing additional challenges.</p>
<table class="tab-format">
<tr>
<td>Serial No.</td>
<td>Language</td>
<td>Script</td>
</tr>
<tr>
<td>1</td>
<td>Hindi</td>
<td>Devanagari</td>
</tr>
<tr>
<td>2</td>
<td>Sanskrit</td>
<td>Devanagari</td>
</tr>
<tr>
<td>3</td>
<td>Marathi</td>
<td>Devanagari</td>
</tr>
<tr>
<td>4</td>
<td>Konkani</td>
<td>Devanagari</td>
</tr>
<tr>
<td>5</td>
<td>Nepali</td>
<td>Devanagari</td>
</tr>
<tr>
<td>6</td>
<td>Maithili</td>
<td>Devanagari</td>
</tr>
<tr>
<td>7</td>
<td>Sindhi</td>
<td>Devanagari, Perso-Arabic</td>
</tr>
<tr>
<td>8</td>
<td>Bodo</td>
<td>Devanagari</td>
</tr>
<tr>
<td>9</td>
<td>Dogri</td>
<td>Devanagari</td>
</tr>
<tr>
<td>10</td>
<td>Bengali</td>
<td>Bengali</td>
</tr>
<tr>
<td>11</td>
<td>Assamese</td>
<td>Bengali</td>
</tr>
<tr>
<td>12</td>
<td>Manipuri</td>
<td>Bengali, Meetei (Mayak)</td>
</tr>
<tr>
<td>13</td>
<td>Gujarati</td>
<td>Gujarati</td>
</tr>
<tr>
<td>14</td>
<td>Kannada</td>
<td>Kannada</td>
</tr>
<tr>
<td>15</td>
<td>Malayalam</td>
<td>Malayalam</td>
</tr>
<tr>
<td>16</td>
<td>Odia</td>
<td>Odia</td>
</tr>
<tr>
<td>17</td>
<td>Punjabi</td>
<td>Gurmukhi</td>
</tr>
<tr>
<td>18</td>
<td>Tamil</td>
<td>Tamil</td>
</tr>
<tr>
<td>19</td>
<td>Telugu</td>
<td>Telugu</td>
</tr>
<tr>
<td>20</td>
<td>Urdu</td>
<td>Perso-Arabic</td>
</tr>
<tr>
<td>21</td>
<td>Santhali</td>
<td>Ol-Chiki, Devanagari</td>
</tr>
<tr>
<td>22</td>
<td>Kashmiri</td>
<td>Devanagari, Perso-Arabic</td>
</tr>
</table>
<p>The scripts of South Asia share so many common features that a side-by-side comparison
of a few will often reveal structural similarities, even in modern letter forms. They are all
abugidas in which most symbols stand for a consonant with an inherent vowel.The North Indian branch of scripts was, like Brahmi itself, mainly used to write Indo-European languages such as Pali and Sanskrit, and eventually the Hindi, Bengali, and Gujarati
language, though it was also the source for scripts for non-Indo-European languages such
as Tibetan, Mongolian, and Lepcha, as well as many South-East Asian scripts. The South Indian scripts are also derived from Brahmi and, therefore, share many similarities in structural characteristics. For more details visit [[!South-Asian-Scripts]].</p>
<p><a href="#fig_script_development"></a> shows the evolution of Indian scripts over a period of time from Brahmi script.</p>
<figure id="fig_script_development"> <img src="images/Brahmi.jpg" width="617" height="637" alt="Evolution of Indic Scripts"/>
<figcaption>Development of Indian Scripts</figcaption>
</figure>
For more details visit [[!Evolution-of-Indic-Scripts]]</section>
<section id="h_basic_components_of_indian_languages">
<h3>Basic components of Indian languages</h3>
<section id="h_unicode_and_cldr">
<h4>Unicode & CLDR</h4>
<p><dfn id="def_unicode">Unicode</dfn> is the Universal character encoding standard, used for representing text for information processing. Unicode encodes all of the individual characters used for all the written languages of the world. The standards provide information about the character and their use. </p>
<p><dfn id="def_cldr">Common Locale Data Repository</dfn> is the largest standard repository of locale data in the world. It is managed by the Unicode Consortium. It provides locale data in an XML format for use in computer applications. It facilitates locale-related information sharing among applications regardless of their domains. Its goal is to provide basic linguistic information for diverse “locales” in an open, interoperable form.</p>
<p>This data is usable for localizing applications. </p>
<p>Some examples of the information that CLDR gathers for languages and territories are:</p>
<ul>
<li>Date formats </li>
<li>Time Zones </li>
<li>Number formats </li>
<li>Currency and its formats </li>
<li>Measurement Systems</li>
<li>Collation (Sort order) Specification: Sorting, Searching and Matching</li>
<li>Translations of names for language, territory, script, time zones, currencies </li>
<li>Script and exemplar characters used by a language</li>
<li>Calendaring rules, Formats and important dates.</li>
</ul>
<p class="note">Reference URL: [[!CLDR]]</p>
</section>
<section id="h_unicode_normalization">
<h4>Unicode Normalization</h4>
<p>Unicode normalization [[!UAX15]] is a form of text normalization that transforms equivalent sequences of characters into the same representation. Unicode normalization is important in Unicode text processing applications, because it affects the semantics of comparing, searching, and sorting Unicode sequences</p>
<p>When a unique representation is required , a normalized form of Unicode text can be used to eliminate unwanted distinctions. The key part of normalization is to provide a unique canonical order for visually non distinct sequences of combining characters.</p>
<section id="h_canonical_and_compatible_equivalence">
<h5>Canonical & Compatible Equivalence</h5>
<p>Unicode contains numerous characters to maintain compatibility with existing standards, some of which are functionally equivalent to other characters or sequences of characters. Because of this, Unicode defines some code point sequences as equivalent. Unicode provides two notions of equivalence: canonical and compatible.</p>
<p>Canonical equivalence is a form of equivalence that preserves visually and functionally equivalent characters.</p>
<p><a href="#fig_canonical_equivalence"></a> shows the canonical equivalence:</p>
<figure id="fig_canonical_equivalence"> <img src="images/can-eq.jpg" width="547" height="83" alt="Canonical equivalence in Hindi" />
<figcaption>Canonical Equivalence</figcaption>
</figure>
</section>
</section>
<section id="h_unicode_code_charts_devanagari">
<h4>Unicode Code charts – Devanagari & Devanagari Extended</h4>
<p>The following Unicode Character Code chart is per the Unicode Standard:</p>
<figure> <img src="images/code-chart.jpg" width="549" height="777" alt="Devanagari and Devanagari extended Code Chart" />
<figcaption>Unicode Devanagari and Devanagari extended Code Chart</figcaption>
</figure>
<p class="note">The latest version of Unicode online code charts are available at [[!Code-Charts]] . The charts cover all character content reference of the 12 scripts of Indian languages. These files contains an excerpt from the character code tables and list of character names for the latest version of Unicode Standard. </p>
</section>
</section>
</section>
<section id="h_indic_orthographic_syllable_boundaries">
<h2>Indic orthographic syllable boundaries</h2>
<section id="h_need_for_abnf_valid_segmentation">
<h3>Need for ABNF valid segmentation</h3>
<p>ABNF Valid Segmentation based Indic orthographic syllable definition is provided here for correct and standardized representation of Indian languages layout. This will address various issues mentioned in the following sections. </p>
<p>This definition will be useful in order to get the uniform display of Indic layout in the browsers, applications, Digital publishing etc.</p>
</section>
<section id="h_abnf_based_definition_of_indic_syllable">
<h3>ABNF based definition of Indic orthographic syllable</h3>
<p><b>V[m] |{CH}C[v][m]|CH </b></p>
<p>The linguistic definition of Indic orthographic syllable has been mapped to ABNF (Augmented Backus–Naur Form) for the purpose of text segmentation, line breaking , drop letter, letter spacing in horizontal text and vertical text representation. The definition has been elaborated , using examples from various Indic scripts in the table below.</p>
<p>The definition is a combination of 3 rules :</p>
<p>Rule 1 : V[m]</p>
<p>Rule 2 : {CH}C[v][m]</p>
<p>Rule 3 : CH (This rule is applicable only at the end of the word)</p>
V(upper case) is independent vowel<br />
<br />
m is modifier (Anusvara/Visarga/Chandrabindu)<br />
<br />
C is a consonant with inherent vowel which may or may not include a single nukta <br />
<br />
v (lower case) is any dependent vowel or vowel sign (mātrā)<br />
<br />
H is halant / virama<br />
<br />
| is a rule separator<br />
<br />
[ ] - The enclosed items is optional under this bracket<br />
<br />
{} - The enclosed item/items occurs zero or repeated multiple times </section>
<section id="h_abnf_syllabe_definition_use_cases_hindi">
<h3>Various example use cases of ABNF based Indic orthographic syllable definition for Indian languages</h3>
<p><strong>Rule 1 : V[m]</strong></p>
<div>
<table class="tab-format">
<tr>
<td><p> </p></td>
<td><p><strong>V (Vowel) is a syllable</strong></p></td>
<td><p><strong>V+ Modifier is a syllable</strong></p></td>
</tr>
<tr>
<td><p>Hindi </p></td>
<td><p>अ, ई, उ</p></td>
<td><p>अं, उँ, आः</p></td>
</tr>
<tr>
<td><p>Kannada</p></td>
<td><p>ಅ, ಇ</p></td>
<td><p>ಅಂ , ಅಃ </p></td>
</tr>
<tr>
<td><p>Tamil</p></td>
<td><p>அ, ஆ, இ</p></td>
<td><p>NA</p></td>
</tr>
<tr>
<td><p>Telugu</p></td>
<td><p>అ, ఇ,</p></td>
<td><p>అం , ఆః</p></td>
</tr>
<tr>
<td><p>Malayalam</p></td>
<td><p>അ, ഇ, ഉ</p></td>
<td><p>അം, അഃ</p></td>
</tr>
<tr>
<td><p>Bengali</p></td>
<td><p>অ , ই , ঋ</p></td>
<td><p>উঃ , এঁ, আঁ</p></td>
</tr>
<tr>
<td><p>Nepali</p></td>
<td><p>अ, आ, इ, उ</p></td>
<td><p>अँ, अं, उः</p></td>
</tr>
<tr>
<td><p>Manipuri language of Bengali script</p></td>
<td><p>অ, ই, উ</p></td>
<td><p>ওঁ, অং (হোয়)</p></td>
</tr>
<tr>
<td><p>Kashmiri language of Devanagari script</p></td>
<td><p>अ , ऑ ,ऒ ,ऎ </p></td>
<td><p>अँ</p></td>
</tr>
<tr>
<td><p>Maithili</p></td>
<td><p>अ, ई, उ </p></td>
<td><p>अं, उँ, आः </p></td>
</tr>
<tr>
<td><p>Dogri</p></td>
<td><p>अ, ई, उ</p></td>
<td><p>अं</p></td>
</tr>
<tr>
<td><p>Odia</p></td>
<td><p>ଅ, ଈ, ଉ</p></td>
<td><p>ଅଂ, ଉଁ, ଆଃ</p></td>
</tr>
<tr>
<td><p>Punjabi</p></td>
<td><p>ਅ, ਆ, ਇ</p></td>
<td><p>ਇੰ, ਉਂ</p></td>
</tr>
<tr>
<td><p>Sanskrit (Excluding Vedic Extensions)</p></td>
<td><p>अ, ई, उ</p></td>
<td><p>अं, उँ, आः</p></td>
</tr>
<tr>
<td><p>Marathi</p></td>
<td><p>अ, ई, ऐ</p></td>
<td><p>अं, उँ, आः</p></td>
</tr>
<tr>
<td><p>Assamese</p></td>
<td><p>অ , ই , ঈ</p></td>
<td><p>অঁ , অং, আঁ , ইঃ</p></td>
</tr>
<tr>
<td><p>Santhali language of Devanagari script</p></td>
<td><p>अ, ई, उ</p></td>
<td><p>अं, उँ, आः</p></td>
</tr>
<tr>
<td><p>Gujarati</p></td>
<td><p>અ, ઇ, ઈ</p></td>
<td><p>અં, અઃ</p></td>
</tr>
<tr>
<td><p>Konkani</p></td>
<td><p>अ, ई, उ</p></td>
<td><p>अं</p></td>
</tr>
<tr>
<td><p>Bodo</p></td>
<td><p>आ , ओ , ए , उ</p></td>
<td><p>ऐं , ऒं</p></td>
</tr>
<tr>
<td><p>Sindhi language of Devanagari script</p></td>
<td><p>अ , ऊ , ई , ऐ</p></td>
<td><p>ओं , एं , उं</p></td>
</tr>
</table>
<p><b>Rule 2 : {CH}C[v][m]</b></p>
<table class="tab-format">
<tr>
<td><p><strong> </strong></p></td>
<td><p><strong>Consonant is a syllable</strong></p></td>
<td><p><strong>Zero or more Consonant(Nukta *) + Virama sequences followed by consonant (+Nukta*)is a syllable</strong></p></td>
<td><p><strong>Zero or more consonant+ (Nukta*)+ virāma sequences followed by a consonant (+Nukta*) followed by a vowel sign is a syllable</strong></p></td>
<td><p><strong>zero or more consonant+ (Nukta*)+ virāma sequences followed by a consonant (+Nukta*) followed by modifier is a syllable</strong></p></td>
<td><p><strong>zero or more consonant+ (Nukta*)+ virāma sequences followed by a consonant (+Nukta*) followed by a vowel sign and modifier is a syllable</strong></p></td>
</tr>
<tr>
<td><p>Hindi </p></td>
<td><p>र, क, ज, ल, म</p></td>
<td><p>प्प, क्ख,च्त, ज्ज्व, त्क्ल, त्स्न , र्त्स्न्य, फ़्क</p></td>
<td><p>र्ता, र्त्स्न्या, फ़्जी, क्या, स्थि</p></td>
<td><p>तः,स्तं, स्त्रँ, स्तः, फ़्ज़ँ </p></td>
<td><p>र्त्स्न्या: त्स्न्युं, त्स्न्युँ, फ़्ज़ें,हि</p></td>
</tr>
<tr>
<td><p>Kannada</p></td>
<td><p>ರ, ಕ, ಜ, ಲ, ಮ</p></td>
<td><p>ಪ್ಪ, ಕ್ಖ,ಚ್ತ, ಜ್ಜ್ವ, ತ್ಕ್ಲ, ರ್ತ, ರ್ತ್ಸ, ರ್ತ್ಸ್ನ</p></td>
<td><p>ರ್ತಾ, ರ್ತ್ಸ್ನ್ಯಾ , ಖ್ವಾ</p></td>
<td><p>ತಃ, ಸ್ತಂ</p></td>
<td><p>ರ್ತ್ಸ್ನ್ಯಾಃ , ತ್ಸ್ನ್ಯುಂ</p></td>
</tr>
<tr>
<td><p>Tamil</p></td>
<td><p>க, ச, ங</p></td>
<td><p>க்ஷ</p></td>
<td><p>ஶ்ரீ , ஸ்ரீ , ரா</p></td>
<td><p>NA</p></td>
<td><p>NA</p></td>
</tr>
<tr>
<td><p>Telugu</p></td>
<td><p>ర, క, జ, ల</p></td>
<td><p>ప్ప, క్ఖ, చ్త,జ్జ్వ , ర్త్స్న , ర్త్స్న్య</p></td>
<td><p>ర్తా, ర్త్స్న్యా , ఖ్ఖి</p></td>
<td><p>తః, స్తం</p></td>
<td><p>క్కిం , ఖ్ఖిం , గ్గిం</p></td>
</tr>
<tr>
<td><p>Malayalam</p></td>
<td><p>ര, ക, ജ, ല, മ</p></td>
<td><p>പ്പ, ജ്ജ്വ, ത്സ, ക്ത</p></td>
<td><p>ക്ഷി, ത്തി, ത്സാ, ജ്ഞി , മ്മീ</p></td>
<td><p>നഃ, മഃ</p></td>
<td><p> ക്ലി , ത്തിം</p></td>
</tr>
<tr>
<td><p>Bengali</p></td>
<td><p>ক, ঙ, ঘ, ছ</p></td>
<td><p>ক্ক, ষ্ট, ষ্ণ, থ্র</p></td>
<td><p>ণ্যে, ন্ত্রে , গ্নে , গ্নী , ন্ত্রী </p></td>
<td><p>NA</p></td>
<td><p> স্যাঁ, ট্যাঁ, খ্রীঃ, ষ্টাং</p></td>
</tr>
<tr>
<td><p>Nepali</p></td>
<td><p>क छ ड भ </p></td>
<td><p>क्क क्ख ज्ज्व</p></td>
<td><p>र्पे , स्ति</p></td>
<td><p>तः स्त्रं</p></td>
<td><p>त्स्न्युँ</p></td>
</tr>
<tr>
<td><p>Manipuri language of Bengali script</p></td>
<td><p>ক, ল, ম, প </p></td>
<td><p>ন্দ, ক্ত , পৃ, র্জ্জ </p></td>
<td><p>র্তি, (পার্তি) , ঙ্থ্রৈ</p></td>
<td><p>ক্তং (খজিক্তং)</p></td>
<td><p>দাঃ, ন্দ্রাং, প্ত্রেং</p></td>
</tr>
<tr>
<td><p>Kashmiri language of Devanagari script</p></td>
<td><p>र, क, ज, ल</p></td>
<td><p>त्य, थ्व, च्य</p></td>
<td><p>न्यॊ, र्ता प्रा, क्या , प्रॉ</p></td>
<td><p>स्तं</p></td>
<td><p>NA</p></td>
</tr>
<tr>
<td><p>Maithili</p></td>
<td><p>र, क, ज</p></td>
<td><p>क्ख , न्ह, न्ध , फ़्क</p></td>
<td><p>र्ता, र्त्स्न्या, फ़्जी, क्या </p></td>
<td><p>तः,स्तं, स्त्रँ, स्तः</p></td>
<td><p>त्स्न्युं , त्स्न्युँ, फ़्ज़ें </p></td>
</tr>
<tr>
<td><p>Dogri</p></td>
<td><p>क, ज,स ,ल</p></td>
<td><p>ग्ग, द्ध , क्क</p></td>
<td><p>फ्ही , म्मी , ड़ि , क्का</p></td>
<td><p>जं , सं</p></td>
<td><p>यें , च्चैं , रें</p></td>
</tr>
<tr>
<td><p>Odia</p></td>
<td><p>କ, ଜ, ମ, ର, ଳ</p></td>
<td><p>କ୍କ, ଚ୍ଚ, ଟ୍ଟ, ଜ୍ଜ, ନ୍ନ , ଜ୍ଜ୍ୱ , ର୍ଣ୍ଣ, , ର୍ତ୍ସ </p></td>
<td><p>ର୍ତ୍ତା, ଜ୍ଞା, ଜ୍ଞୀ , ସ୍ଥି</p></td>
<td><p>ତଃ, ସ୍ତଂ, ସ୍ତଃ</p></td>
<td><p>ହିଂ</p></td>
</tr>
<tr>
<td><p>Punjabi</p></td>
<td><p>ਕ, ਜ, ਧ,ਵ</p></td>
<td><p>ਪ੍ਰ, ਕ੍ਰ , ਸ੍ਵ</p></td>
<td><p>ਨ੍ਹਾ,ਕੌ,ਹੋ</p></td>
<td><p>ਧੰ, ਯੱ, ਨੰ</p></td>
<td><p>ਮਾਂ, ਪੁੱ, ਚਿੱ </p></td>
</tr>
<tr>
<td><p>Sanskrit (Excluding Vedic Extensions)</p></td>
<td><p> ग,ड,प,र,ण</p></td>
<td><p>ल्म, त्य, ल्प</p></td>
<td><p>क्षे, र्था, यो , प्तो</p></td>
<td><p>तं ,न्तः, मः , प॑ , र॒</p></td>
<td><p>षाः, ताः, स्यां , दी॑ , हि॒</p></td>
</tr>
<tr>
<td><p>Marathi</p></td>
<td><p>ल, ष, ळ</p></td>
<td><p>स्व, क्ष्ण</p></td>
<td><p>व्या, त्स्ना</p></td>
<td><p>कं, स्पं </p></td>
<td><p>त्क्रां,त्र्यां </p></td>
</tr>
<tr>
<td><p>Assamese</p></td>
<td><p>ক , খ, ঘ</p></td>
<td><p>ন্ত্ৰ , ৰ্খ, ৰ্জ , ৰ্ট</p></td>
<td><p>ৰ্কে , ন্হা, ছ্ছা , ম্প্ৰ্দা</p></td>
<td><p>ৰ্নিং , ৰ্ণাং , ট্ৰাং , ৰ্কিং </p></td>
<td><p>NA</p></td>
</tr>
<tr>
<td><p>Santhali language of Devanagari script</p></td>
<td><p>र, क, ज, ल, म</p></td>
<td><p>NA</p></td>
<td><p>र्ता, ड़ि</p></td>
<td><p>तः, कं , मः </p></td>
<td><p>ताः, रें</p></td>
</tr>
<tr>
<td><p>Gujarati</p></td>
<td><p>ર, ક , લ, મ</p></td>
<td><p>ક્ક, દ્ય, સ્ત્ર , ર્જ્જ, ર્પ્ક્ક</p></td>
<td><p>ર્તા,ર્ત્સ્ન્યા, ક્યા</p></td>
<td><p>તઃ, સ્તઃ</p></td>
<td><p>ર્ત્સ્ન્યાઃ, હિં</p></td>
</tr>
<tr>
<td><p>Konkani</p></td>
<td><p>ळ</p></td>
<td> <p>य, स्प, ल्म, स्थ , ल्ल्य</p></td>
<td><p>ज्यु, त्मे, स्त्री, स्तू, भ्रू</p></td>
<td><p>स्कं, स्थं, न्हं, द्वं </p></td>
<td><p>व्हां, म्हों, ल्लें, र्दें</p></td>
</tr>
<tr>
<td><p>Bodo</p></td>
<td><p>ब, फ, ख , ज</p></td>
<td><p>प्ता , ज्ज , ब्ला </p></td>
<td><p>ब्ला , यो , न्दो , न्थि</p></td>
<td><p>सं , रं , गं , न्थं</p></td>
<td><p>खां , दुं </p></td>
</tr>
<tr>
<td><p>Sindhi language of Devanagari script</p></td>
<td><p>क, घ , ज , ग</p></td>
<td><p>क्ट , ग्घ , फ्ख , स्त्र , च्ग़ , न्ज</p></td>
<td><p>बि , लू , यि , क्षी </p></td>
<td><p>धं , धृं , षं</p></td>
<td><p>हिं , सौं , श्रिं </p></td>
</tr>
</table>
<strong> * Nukta within a bracket is optional.Consonant may or may not include Nukta.</strong>
<p><b>Rule 3 : CH</b></p>
<p>This rule is applicable only for those Indian languages where pure consonant appears at the end of the word.</p>
<table class="tab-format">
<tr>
<td><p> </p></td>
<td><p>Examples of Rule3 - Consonant + virama at the end of the word</p></td>
</tr>
<tr>
<td><p>Hindi </p></td>
<td><p>NA</p></td>
</tr>
<tr>
<td><p>Tamil</p></td>
<td><p>வணக்கம் , தமிழ் , எண்ணம், செயல்</p></td>
</tr>
<tr>
<td><p>Kannada</p></td>
<td><p>ಬ್ಯಾಂಕ್</p></td>
</tr>
<tr>
<td><p>Telugu</p></td>
<td><p>క్ , జ్ , ఞ్ </p></td>
</tr>
<tr>
<td><p>Malayalam</p></td>
<td><p>വാക്ക്, ചാക്ക് , നിനക്ക്</p></td>
</tr>
<tr>
<td><p>Bengali</p></td>
<td><p>ত্ (হঠাৎ) , This rule would not be applicable if ৎ is declared as pure consonant. </p></td>
</tr>
<tr>
<td><p>Nepali</p></td>
<td><p>छन्, हुन्, गर्दैनन्, गर्छस्</p></td>
</tr>
<tr>
<td><p>Manipuri language of Bengali script</p></td>
<td><p> খ্বাঙজেৎ</p></td>
</tr>
<tr>
<td><p>Kashmiri language of Devanagari script</p></td>
<td><p> NA</p></td>
</tr>
<tr>
<td><p>Maithili</p></td>
<td><p> NA</p></td>
</tr>
<tr>
<td><p>Dogri</p></td>
<td><p>राह् , ओह् </p></td>
</tr>
<tr>
<td><p>Odia</p></td>
<td><p>NA</p></td>
</tr>
<tr>
<td><p>Punjabi</p></td>
<td><p>NA</p></td>
</tr>
<tr>
<td><p>Sanskrit (Excluding Vedic Extensions)</p></td>
<td><p>तेजस्, मरुत् , माम्</p></td>
</tr>
<tr>
<td><p>Assamese</p></td>
<td><p>ত্ (হঠাৎ) , This rule would not be applicable if ৎ is declared as pure consonant. </p></td>
</tr>
<tr>
<td><p>Santhali language of Devanagari script</p></td>
<td><p>NA</p></td>
</tr>
<tr>
<td><p>Gujarati</p></td>
<td><p>આત્મસાત્</p></td>
</tr>
<tr>
<td><p>Konkani</p></td>
<td><p>NA</p></td>
</tr>
<tr>
<td><p>Bodo</p></td>
<td><p>NA</p></td>
</tr>
<tr>
<td><p>Sindhi language of Devanagari script</p></td>
<td><p>NA</p></td>
</tr>
</table>
</div>
</section>
</section>
<section id="h_text_segmentation">
<h2>Text segmentation</h2>
<p>A string of Unicode-encoded text often needs to be broken up into text elements programmatically. Common examples of text elements include what users think of as characters, words, lines (more precisely, where line breaks are allowed), and sentences. The precise determination of text elements may vary according to orthographic conventions for a given script or language. The goal of matching user perceptions cannot always be met exactly because the text alone does not always contain enough information to unambiguously decide boundaries. For example, the period (U+002E FULL STOP) is used ambiguously, sometimes for end-of-sentence purposes, sometimes for abbreviations, and sometimes for numbers. In most cases, however, programmatic text boundaries can match user perceptions quite closely, although sometimes the best that can be done is not to surprise the user. Word boundaries are used in a number of different contexts. The most familiar ones are selection (double-click mouse selection, or “move to next word” control-arrow keys), and “Whole Word Search” for search and replace. They are also used in database queries, to determine whether elements are within a certain number of words of one another .
Grapheme cluster boundaries are important for collation, regular expressions, UI interactions (such as mouse selection, arrow key movement, backspacing), segmentation for vertical text, identification of boundaries for Initial-letter styling, and counting “character” positions within text. [[!UAX29]]</p>
<section>
<h3>Word Boundaries</h3>
<p>Solution for word boundaries:<br />
User-percieved characters boundaries should be based on tailored Grapheme Cluster Boundaries to conform Indic orthographic syllable definition <br />
</p>
<p>In case of Devanagari phrase separator । , U+0964 DEVANAGARI DANDA, (called <i class="foreign">purna viram</i> in Hindi) and ॥ , U+0965 DEVANAGARI DOUBLE DANDA, (<i class="foreign">deergh viram</i> in Hindi) used to mark end of the verse as in Sanskrit text, shlokas etc.),In some of the browsers ending word is selected with <i class="foreign">purna viram</i> on double-click while in some browsers <i class="foreign">purna viram</i> is selected as a separate.So the properties of <i class="foreign">purna viram</i> and <i class="foreign">deergh viram</i> should be same as the properties of FullStop or other punctuation marks so that new line should not begin with <i class="foreign">purna viram</i> and <i class="foreign">deergh viram</i>.</p>
<p>For others characters, the text segmentation should be done as Indic orthographic syllable.</p></section>
<section>
<h3>Typographic units </h3>
<p>Indic script behavior in initial letter styling is based on syllables, rather than individual letter forms.</p>
<img src="images/drop-letter1.jpg" alt="example of drop letter"/>
<p>The above Figure shows an example of a drop intial in Hindi. In the first word of the paragraph, स्कूल ('skūl'), the sequence of characters is stored in memory is as follows:</p>
<img src="images/initial-letter-ex.jpg" alt="initial letter example" />
<p>There are two syllables in this word: SA+VIRAMA+KA+UU and LA. Note, however, that there are three Unicode grapheme clusters here: SA+VIRAMA, KA+UU and LA.</p>
<p>Styling is done on the basis of the whole orthographic syllable, not the first character, nor even the first grapheme. </p>
</section>
</section>
<section id="h_line_breaking">
<h2>Line breaking</h2>
<p>When inline-level content is laid out into lines, it is broken across line boxes. Such a break is called a line break. In most writing systems, in the absence of hyphenation a line break occurs only at word boundaries. Many writing systems use spaces or punctuation to explicitly separate words, and line break opportunities can be identified by these characters. Line breaking, also known as word wrapping, is the process of breaking a section of text into lines such that it will fit in the available width of a page, window or other display area. </p>
<section id="h_hyphenation">
<h3>Hyphenation</h3>
<p> There are different cases of hyphenation, some of the cases are given below :</p>
<p><b>Case 1 :</b> Hyphens are commonly used in Copulative compounds words in Hindi language. Hindi has both prefixes and suffixes which are joined to words with a hyphen.</p>
<p>नर-नारी, लाभ-हानि, माता-पिता, ऊंच-नीच</p>
Case 2:Single word can breaks at the end of the line follow Indic orthographic syllable using hyphen.Following example shows correct representation of word आकर्षण and विज्ञापन using hyphen :
<br />
<img src="images/untitled.jpg" width="537" height="227" alt="Example of Line breaking" /> </section>
<section id="h_guiding_principles_line_breaking_indian_languages">
<h3>Guiding principles of Line breaking for Indian languages</h3>
<p>In Indic writing system , it is preferred that line breaks at word boundaries ,if required following principles may be adhered :</p>
<p><b>Rule 1:</b> New line cannot begin with following symbols/Punctuation marks. Also these should be retain with the associated text</p>
<table class="tab-format">
<tr>
<td><p><strong>Symbols</strong> </p></td>
<td><p><strong>Character name</strong> </p></td>
<td><p><strong>Unicode code-point</strong> </p></td>
</tr>
<tr>
<td><p>। </p></td>
<td><p>DEVANAGARI DANDA </p></td>
<td><p>U + 0964 </p></td>
</tr>
<tr>
<td><p>॥ </p></td>
<td><p>DEVANAGARI DOUBLE DANDA </p></td>
<td><p>U + 0965 </p></td>
</tr>
<tr>
<td><p>) </p></td>
<td><p>RIGHT PARENTHESIS </p></td>
<td><p>U + 0029 </p></td>
</tr>
<tr>
<td><p>+ </p></td>
<td><p>PLUS SIGN </p></td>
<td><p>U + 002B </p></td>
</tr>
<tr>
<td><p>* </p></td>
<td><p>ASTERISK </p></td>
<td><p>U + 002A </p></td>
</tr>
<tr>
<td><p>- </p></td>
<td><p>HYPHENATIONPOINT-VISIBLE HYPHEN<br>
HYPHENATION-SOFT HYPHEN </p></td>
<td><p>U + 2027<br>
U+ 00AD </p></td>
</tr>
<tr>
<td><p>/ </p></td>
<td><p>SOLIDUS </p></td>
<td><p>U + 002F </p></td>
</tr>
<tr>
<td><p>, </p></td>
<td><p>COMMA </p></td>
<td><p>U + 002C </p></td>
</tr>
<tr>
<td><p>. </p></td>
<td><p>FULL STOP </p></td>
<td><p>U + 002E </p></td>
</tr>
<tr>
<td><p>: </p></td>
<td><p>COLON </p></td>
<td><p>U + 003A </p></td>
</tr>
<tr>
<td><p>; </p></td>
<td><p>SEMICOLON </p></td>
<td><p>U + 003B </p></td>
</tr>
<tr>
<td><p>= </p></td>
<td><p>EQUALS SIGN </p></td>
<td><p>U + 003D </p></td>
</tr>
<tr>
<td><p>> </p></td>
<td><p>GREATER-THAN SIGN </p></td>
<td><p>U + 003E </p></td>
</tr>
<tr>
<td><p>] </p></td>
<td><p>RIGHT SQUARE BRACKET </p></td>
<td><p>U + 005D </p></td>
</tr>
<tr>
<td><p>_ </p></td>
<td><p>LOW LINE </p></td>
<td><p>U + 005F </p></td>
</tr>
<tr>
<td><p>| </p></td>
<td><p>VERTICAL LINE </p></td>
<td><p>U + 007C </p></td>
</tr>
<tr>
<td><p>} </p></td>
<td><p>RIGHT CURLY BRACKET </p></td>
<td><p>U + 007D </p></td>
</tr>
<tr>
<td><p>~ </p></td>
<td><p>TILDE </p></td>
<td><p>U + 007E </p></td>
</tr>
<tr>
<td><p>% </p></td>
<td><p>PERCENT SIGN </p></td>
<td><p>U + 0025 </p></td>
</tr>
</table>
Rule 2: The definition of Indic orthographic syllable may be used to break the line and a hyphen should be at the breaking point so that word can be read intuitively
However the language specific morpho-phonemic rules and industry practices (from media, publishing and grammar books) could be used for hyphenation. U+ 00AD (soft hyphen) is used in some languages such as Tamil and Malayalam.
<p><b>Rule 3: </b>The hyphenated words can be broken at the hyphen e.g.:</p>
<ul>
<li>नर-नारी should be treated as:</li>
<li>नर- on the first line and नारी on the next line</li>
</ul>
<p><img src="images/hyphen1.jpg" alt="hyphenation example at line breaking" width="793" height="377" /></p>
<p><b>Rule 4:</b> Expression with mathematical symbol should be treated as single unit so that at the end of the line expression should not breaks at operator level</p>
<p><b>Rule 5:</b> Breaking should not be allowed at numerical values such as currency values, year etc. e.g.</p>
<p>“100.00” or “10,000”, nor in “12:59”</p>
</section>
</section>
<section id="h_initial_letter_styling">
<h3>Initial letter styling</h3>
<p>Drop initial is a typographic effect emphasizing the initial letter(s) of a block element with a presentation similar to a 'floated' element.</p>
<section id="h_selecting_initial_letters">
<h4>Selecting initial letters</h4>
<p>Initial letters in Indic scripts must be selected on the basis of orthographic syllables, rather than individual letter forms (see an example at the end of <a href="#h_text_segmentation"></a>). A detailed definition of Indic syllables can be found in <a href="#h_indic_orthographic_syllable_boundaries"></a>. In Indian languages the size of the initial letter is determined by the number of the lines between the top line of the syllable and the lowest bit in the orthographic Indic syllable cluster where subjoined consonant and other diacritics appear.</p></section>
<section id="h_typical_drop_initial_usage_in_indic_scripts">
<h4>Typical drop initial usage in Indic scripts</h4>
<p>Most of the Indic drop initial letters in magazines and newspapers use 2 to 4 line drops. Some examples are shown below.</p>
<figure> <img src="images/dropcap-example2.png" alt="examples of indic initial letters" />
<figcaption>Examples of Indic Initial letters</figcaption>
</figure>
<p>The <a href="https://www.w3.org/TR/dpub-latinreq/#raised-caps-and-sunken-caps">sunken and raised</a> initial letter are not preferred in Indian languages. In the above examples , reference points on the drop cap must align precisely with reference points in the text. .In Indic scripts the top reference point is the hanging base line for those scripts that have one, and the mean/median line for those that don't, and the bottom alignment point is the text after-edge</p>
<p><a href="https://www.w3.org/TR/css-inline-3/#initial-letter-wrapping">Initial letter wrap property</a> is not applicable for Indian languages. No <a href="https://www.w3.org/TR/css-inline-3/#initial-letter-wrapping">contour-filling</a> is required in Indian languages.</p>
<p>Alignment of the top line of the non-highlighted characters at the top of the thicker top line of the initial letter is common in India. In some examples the top lines of the initial letter and the following letters don't touch. This is due to variable technology/formats used by the publishers. It is preferred that both the top lines of Initial letter and neighbouring text should touch.</p>
<p>Here are some additional examples of initial highlighted letter and drop letter based on the Indic syllable definition.</p>
<p class="exampleList"><img src="images/I-letter1.png" alt="Bengali example" /></p>
<p class="exampleList"><img src="images/I-letter2.png" alt="Punjabi example" /></p>
<p class="exampleList"><img src="images/I-letter3.png" alt="Tamil example"/></p>
<p class="exampleList"><img src="images/I-letter5.png" alt="Malayalam example"/></p>
<p class="exampleList"><img src="images/I-letter4.png" alt="Odia example"/></p>
<p class="exampleList"><img src="images/I-letter6.png" alt="Marathi example" width="555" height="255"/></p>