mapbox-gl
Version:
A WebGL interactive maps library
248 lines (231 loc) • 11.9 kB
JavaScript
'use strict';
/* eslint-disable new-cap */
const isChar = require('./is_char_in_unicode_block');
module.exports.allowsIdeographicBreaking = function(chars) {
for (const char of chars) {
if (!exports.charAllowsIdeographicBreaking(char.charCodeAt(0))) return false;
}
return true;
};
module.exports.allowsVerticalWritingMode = function(chars) {
for (const char of chars) {
if (exports.charHasUprightVerticalOrientation(char.charCodeAt(0))) return true;
}
return false;
};
module.exports.charAllowsIdeographicBreaking = function(char) {
// Return early for characters outside all ideographic ranges.
if (char < 0x2E80) return false;
if (isChar['Bopomofo Extended'](char)) return true;
if (isChar['Bopomofo'](char)) return true;
if (isChar['CJK Compatibility Forms'](char)) return true;
if (isChar['CJK Compatibility Ideographs'](char)) return true;
if (isChar['CJK Compatibility'](char)) return true;
if (isChar['CJK Radicals Supplement'](char)) return true;
if (isChar['CJK Strokes'](char)) return true;
if (isChar['CJK Symbols and Punctuation'](char)) return true;
if (isChar['CJK Unified Ideographs Extension A'](char)) return true;
if (isChar['CJK Unified Ideographs'](char)) return true;
if (isChar['Enclosed CJK Letters and Months'](char)) return true;
if (isChar['Halfwidth and Fullwidth Forms'](char)) return true;
if (isChar['Hiragana'](char)) return true;
if (isChar['Ideographic Description Characters'](char)) return true;
if (isChar['Kangxi Radicals'](char)) return true;
if (isChar['Katakana Phonetic Extensions'](char)) return true;
if (isChar['Katakana'](char)) return true;
if (isChar['Vertical Forms'](char)) return true;
if (isChar['Yi Radicals'](char)) return true;
if (isChar['Yi Syllables'](char)) return true;
return false;
};
// The following logic comes from
// <http://www.unicode.org/Public/vertical/revision-16/VerticalOrientation-16.txt>.
// The data file denotes with “U” or “Tu” any codepoint that may be drawn
// upright in vertical text but does not distinguish between upright and
// “neutral” characters.
// Blocks in the Unicode supplementary planes are excluded from this module due
// to <https://github.com/mapbox/mapbox-gl/issues/29>.
/**
* Returns true if the given Unicode codepoint identifies a character with
* upright orientation.
*
* A character has upright orientation if it is drawn upright (unrotated)
* whether the line is oriented horizontally or vertically, even if both
* adjacent characters can be rotated. For example, a Chinese character is
* always drawn upright. An uprightly oriented character causes an adjacent
* “neutral” character to be drawn upright as well.
*/
exports.charHasUprightVerticalOrientation = function(char) {
if (char === 0x02EA /* modifier letter yin departing tone mark */ ||
char === 0x02EB /* modifier letter yang departing tone mark */) {
return true;
}
// Return early for characters outside all ranges whose characters remain
// upright in vertical writing mode.
if (char < 0x1100) return false;
if (isChar['Bopomofo Extended'](char)) return true;
if (isChar['Bopomofo'](char)) return true;
if (isChar['CJK Compatibility Forms'](char)) {
if (!(char >= 0xFE49 /* dashed overline */ && char <= 0xFE4F /* wavy low line */)) {
return true;
}
}
if (isChar['CJK Compatibility Ideographs'](char)) return true;
if (isChar['CJK Compatibility'](char)) return true;
if (isChar['CJK Radicals Supplement'](char)) return true;
if (isChar['CJK Strokes'](char)) return true;
if (isChar['CJK Symbols and Punctuation'](char)) {
if (!(char >= 0x3008 /* left angle bracket */ && char <= 0x3011 /* right black lenticular bracket */) &&
!(char >= 0x3014 /* left tortoise shell bracket */ && char <= 0x301F /* low double prime quotation mark */) &&
char !== 0x3030 /* wavy dash */) {
return true;
}
}
if (isChar['CJK Unified Ideographs Extension A'](char)) return true;
if (isChar['CJK Unified Ideographs'](char)) return true;
if (isChar['Enclosed CJK Letters and Months'](char)) return true;
if (isChar['Hangul Compatibility Jamo'](char)) return true;
if (isChar['Hangul Jamo Extended-A'](char)) return true;
if (isChar['Hangul Jamo Extended-B'](char)) return true;
if (isChar['Hangul Jamo'](char)) return true;
if (isChar['Hangul Syllables'](char)) return true;
if (isChar['Hiragana'](char)) return true;
if (isChar['Ideographic Description Characters'](char)) return true;
if (isChar['Kanbun'](char)) return true;
if (isChar['Kangxi Radicals'](char)) return true;
if (isChar['Katakana Phonetic Extensions'](char)) return true;
if (isChar['Katakana'](char)) {
if (char !== 0x30FC /* katakana-hiragana prolonged sound mark */) {
return true;
}
}
if (isChar['Halfwidth and Fullwidth Forms'](char)) {
if (char !== 0xFF08 /* fullwidth left parenthesis */ &&
char !== 0xFF09 /* fullwidth right parenthesis */ &&
char !== 0xFF0D /* fullwidth hyphen-minus */ &&
!(char >= 0xFF1A /* fullwidth colon */ && char <= 0xFF1E /* fullwidth greater-than sign */) &&
char !== 0xFF3B /* fullwidth left square bracket */ &&
char !== 0xFF3D /* fullwidth right square bracket */ &&
char !== 0xFF3F /* fullwidth low line */ &&
!(char >= 0xFF5B /* fullwidth left curly bracket */ && char <= 0xFFDF) &&
char !== 0xFFE3 /* fullwidth macron */ &&
!(char >= 0xFFE8 /* halfwidth forms light vertical */ && char <= 0xFFEF)) {
return true;
}
}
if (isChar['Small Form Variants'](char)) {
if (!(char >= 0xFE58 /* small em dash */ && char <= 0xFE5E /* small right tortoise shell bracket */) &&
!(char >= 0xFE63 /* small hyphen-minus */ && char <= 0xFE66 /* small equals sign */)) {
return true;
}
}
if (isChar['Unified Canadian Aboriginal Syllabics'](char)) return true;
if (isChar['Unified Canadian Aboriginal Syllabics Extended'](char)) return true;
if (isChar['Vertical Forms'](char)) return true;
if (isChar['Yijing Hexagram Symbols'](char)) return true;
if (isChar['Yi Syllables'](char)) return true;
if (isChar['Yi Radicals'](char)) return true;
return false;
};
/**
* Returns true if the given Unicode codepoint identifies a character with
* neutral orientation.
*
* A character has neutral orientation if it may be drawn rotated or unrotated
* when the line is oriented vertically, depending on the orientation of the
* adjacent characters. For example, along a verticlly oriented line, the vulgar
* fraction ½ is drawn upright among Chinese characters but rotated among Latin
* letters. A neutrally oriented character does not influence whether an
* adjacent character is drawn upright or rotated.
*/
exports.charHasNeutralVerticalOrientation = function(char) {
if (isChar['Latin-1 Supplement'](char)) {
if (char === 0x00A7 /* section sign */ ||
char === 0x00A9 /* copyright sign */ ||
char === 0x00AE /* registered sign */ ||
char === 0x00B1 /* plus-minus sign */ ||
char === 0x00BC /* vulgar fraction one quarter */ ||
char === 0x00BD /* vulgar fraction one half */ ||
char === 0x00BE /* vulgar fraction three quarters */ ||
char === 0x00D7 /* multiplication sign */ ||
char === 0x00F7 /* division sign */) {
return true;
}
}
if (isChar['General Punctuation'](char)) {
if (char === 0x2016 /* double vertical line */ ||
char === 0x2020 /* dagger */ ||
char === 0x2021 /* double dagger */ ||
char === 0x2030 /* per mille sign */ ||
char === 0x2031 /* per ten thousand sign */ ||
char === 0x203B /* reference mark */ ||
char === 0x203C /* double exclamation mark */ ||
char === 0x2042 /* asterism */ ||
char === 0x2047 /* double question mark */ ||
char === 0x2048 /* question exclamation mark */ ||
char === 0x2049 /* exclamation question mark */ ||
char === 0x2051 /* two asterisks aligned vertically */) {
return true;
}
}
if (isChar['Letterlike Symbols'](char)) return true;
if (isChar['Number Forms'](char)) return true;
if (isChar['Miscellaneous Technical'](char)) {
if ((char >= 0x2300 /* diameter sign */ && char <= 0x2307 /* wavy line */) ||
(char >= 0x230C /* bottom right crop */ && char <= 0x231F /* bottom right corner */) ||
(char >= 0x2324 /* up arrowhead between two horizontal bars */ && char <= 0x2328 /* keyboard */) ||
char === 0x232B /* erase to the left */ ||
(char >= 0x237D /* shouldered open box */ && char <= 0x239A /* clear screen symbol */) ||
(char >= 0x23BE /* dentistry symbol light vertical and top right */ && char <= 0x23CD /* square foot */) ||
char === 0x23CF /* eject symbol */ ||
(char >= 0x23D1 /* metrical breve */ && char <= 0x23DB /* fuse */) ||
(char >= 0x23E2 /* white trapezium */ && char <= 0x23FF)) {
return true;
}
}
if (isChar['Control Pictures'](char) && char !== 0x2423 /* open box */) return true;
if (isChar['Optical Character Recognition'](char)) return true;
if (isChar['Enclosed Alphanumerics'](char)) return true;
if (isChar['Geometric Shapes'](char)) return true;
if (isChar['Miscellaneous Symbols'](char)) {
if (!(char >= 0x261A /* black left pointing index */ && char <= 0x261F /* white down pointing index */)) {
return true;
}
}
if (isChar['Miscellaneous Symbols and Arrows'](char)) {
if ((char >= 0x2B12 /* square with top half black */ && char <= 0x2B2F /* white vertical ellipse */) ||
(char >= 0x2B50 /* white medium star */ && char <= 0x2B59 /* heavy circled saltire */) ||
(char >= 0x2BB8 /* upwards white arrow from bar with horizontal bar */ && char <= 0x2BEB)) {
return true;
}
}
if (isChar['CJK Symbols and Punctuation'](char)) return true;
if (isChar['Katakana'](char)) return true;
if (isChar['Private Use Area'](char)) return true;
if (isChar['CJK Compatibility Forms'](char)) return true;
if (isChar['Small Form Variants'](char)) return true;
if (isChar['Halfwidth and Fullwidth Forms'](char)) return true;
if (char === 0x221E /* infinity */ ||
char === 0x2234 /* therefore */ ||
char === 0x2235 /* because */ ||
(char >= 0x2700 /* black safety scissors */ && char <= 0x2767 /* rotated floral heart bullet */) ||
(char >= 0x2776 /* dingbat negative circled digit one */ && char <= 0x2793 /* dingbat negative circled sans-serif number ten */) ||
char === 0xFFFC /* object replacement character */ ||
char === 0xFFFD /* replacement character */) {
return true;
}
return false;
};
/**
* Returns true if the given Unicode codepoint identifies a character with
* rotated orientation.
*
* A character has rotated orientation if it is drawn rotated when the line is
* oriented vertically, even if both adjacent characters are upright. For
* example, a Latin letter is drawn rotated along a vertical line. A rotated
* character causes an adjacent “neutral” character to be drawn rotated as well.
*/
exports.charHasRotatedVerticalOrientation = function(char) {
return !(exports.charHasUprightVerticalOrientation(char) ||
exports.charHasNeutralVerticalOrientation(char));
};