The SignPuddle Standard for SignWriting Text
draft-slevinski-signwriting-text-07

Abstract

For concreteness, because the universal character set is not yet universal, and because an international standard for the internet community should be documented and stable, this I-D has been released with the intention of producing an RFC to document the character use and naming conventions of the SignWriting community on the Internet.

The SignWriting Script is an international standard for writing sign languages by hand or with computers. From education to research, from entertainment to religion, SignWriting has proven useful because people are using it to write signed languages. The SignWriting Script has two major families: Block Printing for the reader and Handwriting for the writer.

Formal SignWriting uses ASCII strings to name logographic signs. The mathematical names are explained with tokens and regular expression patterns. Symbol keys reference the symbols of the International SignWriting Alphabet 2010. Coordinates define X and Y number values for 2-dimensional placement. Signs are written in a spatial SignBox, where each symbol is positioned with a 2-dimension coordinate. For sorting, each sign can have an optional temporal sequence of symbols that is outside of the SignBox and the visible text. To create sentences, completed signs are written sequentially, interspersed with punctuation symbols.

The query language of Formal SignWriting uses a lite markup, similar to FSW, to define a variety of searching possibilities. The spatial SignBox can be searched for symbols or ranges of symbols. For each symbol or range, the search can specify if the symbol only needs to be found somewhere in the SignBox, or if the symbol needs to be found near certain coordinates. The temporal sequence can be searched for starting symbols, written as a sequential list of symbols and ranges of symbols. When searching the temporal sequence, the search results will be limited to signs that start with a matching temporal sequence. Each query string is transformed into one or more regular expressions. The regular expressions are used to quickly search large amounts of data.

The styling string of Formal SignWriting uses a lite markup to define a variety of styling options. The entire sign can be customized for padding, coloring, and size. Individual symbols within a sign can be customized for coloring and size.

SignWriting 2010 is the modern implementation and international specification of the SignWriting Script for the internet community that includes TrueType Fonts and a compact JavaScript library. SignMaker is a standards based editor, utilizing HTML, CSS, JavaScript, SVG, TrueType Fonts, and PNG images. SignMaker can be used to create a private dictionary or to view dozens of sign language dictionaries derived from SignPuddle Online.

For Unicode, there are several encodings possibilities. Formal SignWriting is UTF-8. The plane 15 encoding is isomorphic with Formal SignWriting strings, using 3 characters for each symbol, along with structural marker characters and number characters. The plane 16 encoding is focused on the symbols only, using 1 character for each symbol. The Unicode 8 specification uses 1 to 3 characters on plane 1 to name each symbol of the International SignWriting Alphabet 2010.

Three appendices discuss additional topics to the standard. The first discusses the Modern SignWriting theory and example document, stable since January 12, 2012. The second discusses the symbol encoding of the International SignWriting Alphabet 2010. The third discusses the SignPuddle Standards: licences, infrastructure, and compatibility.

This memo concretely defines a conceptual character encoding map for the Internet community. It is published for reference, examination, implementation, and evaluation. Distribution of this memo is unlimited.

Status of This Memo

This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79.

Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet-Drafts is at http://datatracker.ietf.org/drafts/current/.

Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress."

This Internet-Draft will expire on November 10, 2016.

Copyright Notice

Copyright (c) 2016 IETF Trust and the persons identified as the document authors. All rights reserved.

This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.

Table of Contents

• 1. SignWriting Script
• 1.1. 2-Dimensional Signs
• 1.2. Punctuation and Text
• 1.3. Block Printing
• 1.4. Handwriting
• 2. Formal SignWriting
• 2.1. Symbol Keys
• 2.2. Coordinates
• 2.3. Spatial SignBox
• 2.4. Temporal Sequence
• 2.5. Sentences
• 3. Query Language
• 3.1. Searching the Spatial Signbox
• 3.2. Searching the Temporal Sequence
• 3.3. Transformation to Regular Expression
• 4. Styling String
• 4.1. Styling the Entire Sign
• 4.1.1. Colorize
• 4.1.2. Padding
• 4.1.3. Background
• 4.1.4. Detail Colors
• 4.1.5. Zoom Level
• 4.2. Styling Individual Symbols
• 4.2.1. Detail Colors
• 4.2.2. Zoom Level
• 5. SignWriting 2010
• 5.1. Font Creation Tools
• 5.2. TrueType Fonts
• 5.3. JavaScript Library
• 5.4. SignMaker Editor
• 6. Unicode Integration
• 6.1. UTF-8
• 6.2. Private Use Area Plane 15
• 6.3. Private Use Area Plane 16
• 6.4. Unicode 8
• 7. IANA Considerations
• 8. Security Considerations
• 9. References
• Appendix A. Modern SignWriting
• Appendix B. International SignWriting Alphabet 2010
• B.1. Grapheme
• B.2. Symbol
• B.3. Hierarchy
• B.4. Combined Character Sequence
• B.5. Validity
• Appendix C. SignPuddle Standard
• C.1. Licenses
• C.2. Infrastructure
• C.2.1. SignPuddle Online
• C.2.2. SignWriting Server
• C.2.3. SignWriting Icon Server
• C.2.4. Wikimedia Incubator
• C.3. Compatibility
• C.3.1. SignTyp
• C.3.2. SignWriter Studio
• C.3.3. DELEGS Online
• C.3.4. SWift
• C.3.5. JSPad
• Author's Address

1. SignWriting Script

The SignWriting Script is the universal and complete solution for written sign language. It has been applied to a wide and deep international community of sign languages including: American Sign Language, Arabian Sign Languages, Australian Sign Language, Bolivian Sign Language, Brazilian Sign Language, British Sign Language, Catalan Sign Language, Colombian Sign Language, Czech Sign Language, Danish Sign Language, Dutch Sign Language, Ethiopian Sign Language, Finnish Sign Language, Flemish Sign Language, French-Belgian Sign Language, French Sign Language, German Sign Language, Greek Sign Language, Irish Sign Language, Italian Sign Language, Japanese Sign Language, Malawi Sign Language, Malaysian Sign Language, Maltese Sign Language, Mexican Sign Language, Nepalese Sign Language, New Zealand Sign Language, Nicaraguan Sign Language, Norwegian Sign Language, Peruvian Sign Language, Philippines Sign Language, Polish Sign Language, Portugese Sign Language, Quebec Sign Language, South African Sign Language, Spanish Sign Language, Swedish Sign Language, Swiss Sign Language, Taiwanese Sign Language, and Tunisian Sign Language.

Sign language is vastly different than spoken language. Instead of the sequential sounds of the voice, there is a 3 dimensional space with simultaneous action. The SignWriting Script creates 2-dimensional writing that is visually icon and full of featural information. This is true on the symbol level and on the sign level. A symbol represents phonemic information and is full of featural information to better understand the phonemes of the symbols. A sign is a 2-dimensional arrangement of symbols and is full of featural information to better understand the morphemes of the signs.

The SignWriting Script is an international standard for writing sign languages by hand or with computers. From education to research, from entertainment to religion, SignWriting has proven useful because people are using it to write signed languages.

Initially developed in 1974, the script was written exclusively by hand for 12 years. Since then the script has spread around the world and continues to be written on paper and chalkboard.

In 1981, SignWriting Publishing rapidly evolved with Block Printing. In 1986, computerization of the SignWriting Block Printing began. The current symbol encoding of the ISWA 2010 has been stable since the font release on October 20th, 2010. The larger character encoding model has been stable since the initial release of Modern SignWriting on January 12th, 2012.

The 2 families of the SignWriting Script are Handwriting for the writer and Block Printing for the reader. Block Printing uses more features and Handwriting often uses less. Block printing is used in education, publishing, and is the basis of the computerized model.

1.1. 2-Dimensional Signs

A sign is a variably-size logographic word. It is a 2-dimensional combination of symbols inside of a signbox with a tight bounding box and an explicit center. The size of the signbox varies with the symbols written inside.

Inside of a 2-dimensional signbox, the symbols are placed in a freeform, 2-dimensional arrangement. This feature of the script expresses spatial relation directly.

Writing based on vision uses two viewpoints: receptive and expressive. The receptive viewpoint is based on the idea of receiving an image. For the receptive viewpoint, the right hand of a signer will be written on the left side of the signbox. When SignWriting is used for transcription, the receptive view is most often used. The related writing systems of DanceWriting and MovementWriting normally use the receptive viewpoint.

The expressive viewpoint is based on the idea of expressing a concept. For the expressive viewpoint, the right hand of a signer will be written on the right side of the signbox. When SignWriting is used for authorship, the expressive view is most often used.

The are two main writing planes: the front wall (Frontal Plane) and the floor (Transverse Plane). The choice of writing plane can affect the shape of the symbols, such as the fill pattern for the hand shape palms or the tail for the movement arrows.

There are two perspectives: front and top. The front perspective is a straight on view of/from the signer. The top perspective is a top-down view of the signer. Usually, a sign will be written from a single perspective.

1.2. Punctuation and Text

Logographic signs are mixed with punctuation to form text.

Punctuation is a single symbol and separates a series of signs into structured sentences. A punctuation symbol is always used alone and should not be used in a sign. Line breaks should not occur before punctuation.

When written vertically, SignWriting can use 3 different lanes: left, middle, and right. The middle lane is the default lane and punctuation is always used in the middle lane. No matter the lane, the center of a sign is aligned with the center of the lane.

For body weight shifts to one side or the other, the center of the sign is aligned with a fixed horizontal offset from the middle lane into either the left or right lane.

The left and right lanes are used to represent body weight shifts and are represented by a horizontal offset from the middle lane. Body weight shifts are important to the grammar of sign languages, used for two different grammatical aspects: 1) role shifting during sign language storytelling, and 2) spatial comparisons of two items under discussion. One "role" or "item" is placed on the right side of the body (right lane), and the other on the left side of the body (left lane), and the weight shifts back and forth between the two, with the narrator in the middle (middle lane).

1.3. Block Printing

Valerie Sutton writes, "SignWriting Printing is easy to read. It is designed for the reader. The Printing can be written by hand as well as by computer. If I am writing a letter to a friend in ASL, I write the letter in SignWriting Printing, taking the time to make sure that my handwritten-symbols are easy and clear to read. I try to write as clearly as if I were using a computer. Of course it is slower, but it is worth it, knowing that my friend will be able to read my letter!"

With Block Printing, a sign is a cluster of several symbols arranged in 2-dimensions space. Each symbol has a definite appearance and understanding within an established symbol set. The exact form of each symbol is structured, standardized, and highly featural.

Each symbol can have two aspects. The first is the line that defines the positive shape of the symbol. The second aspect is the fill (or negative space) of the symbol that is sometimes used inside the lines for palm facing, and inside some arrow heads and tails. Not every symbol has fill. Fill matters when symbols overlap. The negative space of the symbol on top will cover part of the symbol underneath.

The Block Printing family is aimed at the needs of the reader and the publisher. The Block Printing family has been standardized with a fully developed model.

1.4. Handwriting

Valerie Sutton writes, "SignWriting Handwriting is easier to write by hand, than the Printing. It is designed for the writer. There are several variations of Handwriting, and since most of the time, the writer is only writing for private notes, some writers create their own shortcuts that work just for them...and that is fine!"

The purpose is not to recreate the iconic symbols of the International SignWriting Alphabet exactly by hand, but the purpose is to enable the writer to quickly write notes on paper or chalkboard. Handwriting often drops features of the SignWriting Script for efficiency and speed. If too many features are dropped, the writing may loose it's clarity over time as the writer is distanced from the writing. This is common for Shorthand.

A popular form of SignWriting is cursive. It can be shared among a groups of writers or it can be individualized and personal. Cursive writing is designed to have fluid marks and a natural flow. Cursive writing may use fewer features than the iconic symbols, but the various marks should be related to the standardized symbols in appearance and meaning. Once developed, this style of writing is great for taking notes in a class.

Shorthand is a skill of the proficient writer [SHORTHAND]. In 1982, Sign Language Stenographers could record sign language with SignWriting Shorthand at normal signing speed [STENOGRAPHY]. To develop this skill, practice and special training were required.

The marks of SignWriting Shorthand are a personal style of quick and efficient strokes with a highly developed reception to what signifies meaning. The marks are personal reminders rather than a fully developed text. The shorthand in and of itself is often an incomplete representation of the gestures that were experienced. The shorthand writing can be thought of as a short-term memory device. Often shorthand notes must be revised and extended at a later time, the sooner the better.

2. Formal SignWriting

According to Wikipedia, "In mathematics, computer science, and linguistics, a formal language is a set of strings of symbols that may be constrained by rules that are specific to it." [FORMAL]

Formal SignWriting defines a formal language for the signed languages of the world. Any sign of any sign language can be written as a string of ASCII characters.

Formal SignWriting is a heuristic model. The first prototypes were created in 2008. Through trial and error, the model was successively refactored to reduce the complexity and the computation cost of the implementations. The model has been optimized for common usage and processing. The final model has been stable since January 12th, 2012.

The mathematical names of Formal SignWriting are plain text strings of characters. These names are described with regular expressions. Formal languages and regular expressions are used to solve fundamental problems.

           Y Axis
             | 250
             | 
             |
             |
             |
             |
X Axis       |
  -----------+------------
  250        |         749
             |
             |
             |
             |
             |
             | 749
            

@font-face {
  font-family: "SignWriting 2010";
  src: 
    local('SignWriting 2010'),
    local('SignWriting_2010'),
    url('https://cdn.rawgit.com/Slevinski/signwriting_2010_fonts/\
master/fonts/SignWriting%202010.ttf') format('truetype');
}
@font-face {
  font-family: "SignWriting 2010 Filling";
  src: 
    local('SignWriting 2010 Filling'),
    local('SignWriting_2010_Filling'),
    url('https://cdn.rawgit.com/Slevinski/signwriting_2010_fonts/\
master/fonts/SignWriting%202010%20Filling.ttf') format('truetype');
}