This document specifies a reference set of Label Generation Rules (LGR) for the Oriya (Odia) script for the second level. The starting point for the development of this LGR can be found in the related Root Zone LGR [RZ-LGR-4-Orya]. For details and additional background on the script, see "Proposal for an Oriya Script Root Zone Label Generation Ruleset (LGR)" [Proposal-Oriya]. The format of this file follows [RFC 7940].
While Oriya is the name under which the script is encoded in Unicode, and is therefore used here to formally identify the script, the name Odia has become the preferred name in English for both script and language as it is closer to the pronunciation of their native names.
The repertoire contains 62 code points for letters, covering the Oriya (Odia) language as well as all other languages written with the Oriya script and ranging from 1 to 4 on the [EGIDS] scale. The repertoire is a subset of [Unicode 6.3]. For more detail, see Section 5, "Repertoire" in [Proposal-Oriya]. (The proposal cited has been adopted for the Oriya script portion of the Root Zone LGR.)
For the second level, the repertoire has been augmented with the ASCII digits, U+0030 to U+0039, and U+002D HYPHEN-MINUS for a total of 73 repertoire elements.
Code points outside the Oriya script that are listed in this file are targets for out-of-script variants and are identified by a reflexive (identity) variant of type "out-of-repertoire-var". They do not form part of the repertoire.
Each code point or range is tagged with the script or scripts that the code point is used with, one or more tag values denoting character category, and one or more references documenting sufficient justification for inclusion in the repertoire, see "References" below. Comments provide alternate names of some code points.
This reference LGR is designed for use in zones shared by more than one script. Where appropriate, cross-script variants have been defined to mutually exclude labels from different scripts that could otherwise be substituted by the users. Once a label has been delegated for one script, any variant labels from other scripts consisting of cross-script variants would be blocked. Any label containing at least one code point that is not a cross-script variant would be considered distinct. Because of that, even large numbers of defined cross-script variants generally do not lead to a high percentage of labels experiencing a collision.
This LGR defines one set of cross script variants with the Malayalam script, two sets of cross-script variants with the Myanmar script and no in-script variants. For details, see Section 6, "Variants" in [Proposal-Oriya].
Digit Variants: The Oriya reference LGR does not include native digits, so there are no semantic variants defined. However, one Oriya digit is a near homoglyph of a European digit of a different value. U+0B68 ORIYA DIGIT TWO is a near homoglyph of U+0039 DIGIT NINE. Should an extension be contemplated that adds native digits, adding such a homoglyph variant would require transitive variant relations between the two digits NINE, at which time this conflict would have to be resolved.
Variant Disposition: All variants are of type “blocked”, making labels that differ only by these variants mutually exclusive: whichever label containing either of these variants is chosen earlier would be delegated, while any other equivalent label should be blocked. There is no preference among these variants.
This LGR does not define allocatable variants.
The specification of variants in this reference LGR follows the guidelines in [RFC 8228].
The basic characters in Oriya are classified into eight main categories. They are Consonants, Vowels, Matra, Halant, Nukta, Visarga, Candrabindu and Anusvara.
Consonants: The Oriya script is a syllabic alphabet in which all consonants have an inherent vowel. Diacritics, which can appear above, below, before, or after the consonant they belong to, are used to change the inherent vowel. More details in Section 3.5, "Structured consonants" and Section 3.6, "Unstructured consonants" in [Proposal-Oriya].
Vowels and Matras: A dependent vowel sign or "matra" is used to represent a vowel sound that is not inherent to the consonant. It is always depicted in combination with a single consonant, or with a consonant cluster. When vowels occur independently the are written with standalone vowel letters. More details in Section 3.12, "Matra sign (Dependent Vowel)" in [Proposal-Oriya].
Halant: A Halant, also known as Virama, is used after a consonant to "strip" it of its inherent vowel. The Halant form of a consonant is the form produced by adding the Halant, encoded as U+0B4D ( ୍ ) ORIYA SIGN VIRAMA to the nominal shape. A Halant follows all but the last consonant in every Oriya syllable. More details in Section 3.7, "The Implicit Vowel Killer Halant" in [Proposal-Oriya].
Nukta: The nukta sign ( ଼ ) is used in the Oriya language just like in many other scripts used in South Asia. It can be commonly used with U+0B21 ( ଡ ), U+0B22 ( ଢ ). More details in Section 3.8, "Nukta" in [Proposal-Oriya].
Visarga: U+0B03 ORIYA SIGN VISARGA is frequently used in Sanskrit and represents a sound very close to /h/. More details in Section 3.9, "Visarga & Avagraha" in [Proposal-Oriya].
Candrabindu: The Candrabindu denotes nasalization of the preceding vowel and consonants as in ଅଁଳା /ãala/name of seasonal fruit (U+0B05 U+0B01 U+0B33 U+0B3E). Oriya users commonly use it for writing the words and sounds of Sanskrit. More details in Section 3.10, "Nasalization: Candrabindu" in [Proposal-Oriya].
Anusvara: Anusvara replaces a conjunct group of a Nasal Consonant+Halant+Consonant belonging to a particular varga (plosive). The Anusvara represents a homorganic nasal. Before a non-varga consonant (non-plosive) the Anusvara represents a nasal sound. More details in Section 3.11, "Anusvara" in [Proposal-Oriya].
Actions include the default actions for LGRs as well as that needed to invalidate labels with misplaced combining marks. They are marked with ⍟. For a description see [RFC 7940].
These rules have been formulated so that they can be adopted for LGR specification.
The following symbols are used in the WLE rules:
C → Consonant
M → Matra
V → Vowel
B → Anusvara
H → Halant
N → Nukta
C1 → Consonants used with Nukta
X → Visarga
D → Candrabindu
The rules are:
More details in Section 7, Whole Label Evaluation Rules (WLE)" in [Proposal-Oriya].
This reference LGR for Oriya for the 2nd Level has been developed by Michel Suignard and Asmus Freytag, based on the Root Zone LGR for Oriya and information contained or referenced therein, see [RZ-LGR-4-Orya]. Suitable extensions for the second level have been applied according to the [Guidelines]. The original proposal for a Root Zone LGR for the Oriya script, that this reference LGR is based on, was developed by the Neo-Brahmi Generation Panel. (NBGP) For more information on methodology and contributors to the underlying Root Zone LGR, see Sections 4 and 8 in [Proposal-Oriya], as well as [RZ-LGR-Overview].
The following general references are cited in this document:
For references consulted particularly in designing the repertoire for the Oriya script for the second level please see details in the Table of References below. References [0] and [6] refer to the Unicode Standard versions in which the corresponding code points were initially encoded. References [101] and above correspond to sources given in [Proposal-Oriya] justifying the inclusion of the corresponding code points. Entries in the table may have multiple source reference values. Reference [150] indicates the source for common rules.
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