Seven-Segment Type

This library provides functionality for displaying text on seven-segment display panels. It makes use of a standardized typeface that currently covers the following characters:

• Numerals
• Punctuation
• Alphabets (both uppercase and lowercase):
  • Latin alphabet, including many supplemental characters and diacritics
  • Greek alphabet, including some accented characters
  • Cyrillic alphabet, including some supplemental characters
• Japanese Katakana, with mappings from Hiragana
• Korean Hangul Jamo

Locales can be specified to improve the mapping of characters, particularly diacritics. For example, for the German ('de') locale, the characters Ä, Ö and Ü are mapped to AE, OE and UE, but by default to A, O and U.

Development page with all the characters

Usage

const sstGeneral = new SevenSegmentType()
const sstGerman = new SevenSegmentType({
  locales: ['de']
})
const sstMultiLang = new SevenSegmentType({
  // Ü would map to UE even in French text
  locales: ['fr', 'it', 'de']
})

const text = "Text to be displayed"

const displayLine = sstGeneral.convert(text)

// String to be rendered with the DSEG font
const stringOutput = displayLine.toDsegString()

// Formats useful for feeding to seven segment displays
const byteArray = displayLine.toBytes()
const pinsLine = displayLine.toPinsArray({
  // if some other pin mapping is more convenient
  pinMap: [0,6,2,4,3,5,1,7]
})

// Splitting the text for a panel with a width of 24 seven segment displays
sstGeneral.convert(multiLineText).split(24).forEach(line =>
{
  line.toBytes()
})
// Splitting takes into account spaces, newline and soft/hard hyphenation characters

// One liner
sstGeneral.convert(text).toDsegString()

The font to use is DSEG font v0.50beta1. The current NPM stable release does not include the correct structure for displaying the characters programmatically.

Stylistic Choice

• Characters are allowed to look the same as the numerals.
• Lowercase letters are generally designed to have more weight in the lower 4 segments and to never have the upper 4 segments all lit at once, ensuring a distinct visual difference from uppercase letters. This may require the "invention" of some new characters, which may take some time to become familiar with and read fluently at first.
• Uppercase and lowercase letters should ideally all be distinct from one another.
• Aside from its numerical usage, the decimal point (DP) is used to mark unknown characters or variations of diacritics or letters. However, it should be used sparingly as some displays might not include it.

Help required

Potential areas for improvement:

• Languages using the Latin alphabet with diacritics
• Greek
• Languages using Cyrillic
• Hiragana (Maybe)
• Korean
• Any other writing systems

This project needs contributors who are native speakers or highly familiar with the languages being worked on as it's important to have a strong sense of how words in these languages are meant to look. This helps determine whether they remain visually recognizable and aesthetically pleasing on seven-segment displays.

Many diacritics map to the same seven-segment characters, so adjustments may be necessary for each language to better differentiate them.

Don't hesitate to suggest major changes, as this project is still very much a work in progress.

Development

Dev Web View

To view all the characters in use on a web page, run:

yarn dev

Build

To build the library, run:

yarn build