Iosevka/font-src/gen/ttfa-controls/index.mjs
2023-11-10 03:33:40 -08:00

104 lines
2.7 KiB
JavaScript

import ttfaRanges from "../../generated/ttfa-ranges.mjs";
import * as Gr from "../../support/gr.mjs";
import { ArrayUtil } from "../../support/utils.mjs";
export async function generateTtfaControls(gsOrig, gsTtf) {
let ttfaControls = [`# Machine generated. Do not modify.`];
let alignments = [];
for (const cfg of ttfaRanges) {
const alignment = new Alignment(cfg.scriptTag, cfg.featureTag, cfg.ranges);
alignment.collectDefault(gsOrig, gsTtf);
alignments.push(alignment);
}
for (const go of gsOrig.glyphs()) {
const hc = Gr.HintClass.get(go);
if (!hc) continue;
const gd = gsTtf.queryBySourceGlyph(go);
if (!gd) continue;
const [s, f] = hc;
for (const alignment of alignments) {
if (s === alignment.scriptTag && f === alignment.featureTag)
alignment.allGlyphs.set(go, gd);
}
}
for (const alignment of alignments) {
alignment.extend(gsOrig, gsTtf);
alignment.write(ttfaControls, gsTtf);
}
return ttfaControls;
}
class Alignment {
constructor(scriptTag, featureTag, ranges) {
this.scriptTag = scriptTag;
this.featureTag = featureTag;
this.ranges = ranges;
this.defaultGlyphs = new Map();
this.allGlyphs = new Map();
}
collectDefault(gsOrig, gsTtf) {
for (const [lo, hi] of this.ranges) {
for (let lch = lo; lch <= hi; lch++) {
const go = gsOrig.queryByUnicode(lch);
if (!go) continue;
const gd = gsTtf.queryBySourceGlyph(go);
if (!gd) continue;
this.allGlyphs.set(go, gd);
this.defaultGlyphs.set(go, gd);
}
}
}
extend(gsOrig, gsTtf) {
for (;;) {
let sizeBefore = this.allGlyphs.size;
for (const [go, gd] of this.allGlyphs) {
const cvs = [
...Gr.AnyCv.query(go),
Gr.Texture.ExtL,
Gr.Texture.ExtR,
Gr.Texture.ExtLR,
Gr.Texture.ShrL,
Gr.Texture.ShrR,
Gr.Texture.ShrLR
];
for (const gr of cvs) {
const gnLinked = gr.get(go);
if (!gnLinked) continue;
const goLinked = gsOrig.queryByName(gnLinked);
if (!goLinked) continue;
const gdLinked = gsTtf.queryBySourceGlyph(goLinked);
if (!gdLinked) continue;
this.allGlyphs.set(goLinked, gdLinked);
}
}
let sizeAfter = this.allGlyphs.size;
if (sizeAfter <= sizeBefore) break;
}
}
write(sink, gsTtf) {
const gOrd = gsTtf.decideOrder();
let nonDefaultGlyphIndices = [];
for (const [go, gd] of this.allGlyphs) {
if (this.defaultGlyphs.has(go)) continue;
nonDefaultGlyphIndices.push(gOrd.reverse(gd));
}
if (!nonDefaultGlyphIndices.length) return;
const glyphIndicesRangesStr = ArrayUtil.toRanges(nonDefaultGlyphIndices)
.map(([lo, hi]) => (lo === hi ? `${lo}` : `${lo}-${hi}`))
.join(", ");
sink.push(`${this.scriptTag} ${this.featureTag} @ ${glyphIndicesRangesStr}`);
}
}