@sutton-signwriting/font-db
Version:
a javascript package for node that generates SVG and PNG images for individual symbols and complete signs
77 lines (72 loc) • 2.66 kB
JavaScript
const { svg2png } = require('../common/svg2png')
const { symbolSvg } = require('./swu-symbol-svg');
const fs = require('fs');
/**
* Function that creates a binary PNG image from an SWU symbol key with an optional style string
* @function swu.symbolPng
* @param {string} swuSym - an SWU symbol key with optional style string
* @param {{width:(number|undefined),height:(number|undefined)}} [scale] - options for scaling to specific width or height
* @returns {ArrayBuffer} symbol png
* @example
* // using promise.then
* swu.symbolPng('-C').then( png => {
* console.log(png)
* })
* @example
* // using promise.then with options which scales the image to 100 pixels width
* swu.symbolPng('-C', { width: 100 }).then( png => {
* console.log(png)
* })
* @example
* // using async/await
* const png = await swu.symbolPng('-C')
* @example
* // using async/await with options which scales the image to 100 pixels width
* const png = await swu.symbolPng('-C', { width: 100 })
*/
const symbolPng = async (swuSym, scale) => {
let svg = await symbolSvg(swuSym);
svg = svg.replace(/<text.*text>/g, "");
const png = await svg2png(svg, scale);
return png;
}
/**
* Function that creates a data url PNG image from an SWU symbol key with an optional stle string
* @function swu.symbolPngDataUrl
* @param {string} swuSym - an SWU symbol key with optional style string
* @param {{width:(number|undefined),height:(number|undefined)}} [scale] - options for scaling to specific width or height
* @returns {string} symbol png
* @example
* // using promise.then
* swu.symbolPndDataUrl('-C').then( png => {
* console.log(png)
* })
* @example
* // using promise.then with options which scales the image to 100 pixels width
* swu.symbolPndDataUrl('-C', { width: 100 }).then( png => {
* console.log(png)
* })
* @example
* // using async/await
* const png = await swu.symbolPndDataUrl('-C')
* @example
* // using async/await with options which scales the image to 100 pixels width
* const png = await swu.symbolPndDataUrl('-C', { width: 100 })
*/
const symbolPngDataUrl = async (swuSym, scale) => {
const res = await symbolPng(swuSym, scale);
return 'data:image/png;base64,' + res.toString('base64');
}
if (require.main === module) {
if (process.argv[3]) {
symbolPng(process.argv[2]).then( res => {
fs.writeFileSync(process.argv[3], res);
})
} else {
symbolPngDataUrl(process.argv[2]).then( res => {
console.log(res)
})
}
} else {
module.exports = { symbolPng, symbolPngDataUrl }
}