Node operates text to generate images

This time I will bring you node operation text generation pictures , what are the precautions for node operation text generation pictures, the following is a practical case, let’s take a look .

Solutions

Convert text to svg -> Convert svg to png -> Merge images

Related wheels

1. images Node.js Lightweight cross-platform image encoding and decoding library, no additional installationdependencies

2. text-to-svg text to svg

3. svg2png svg to png picture

Sample code

'use strict';
const fs = require('fs');
const images = require('images');
const TextToSVG = require('text-to-svg');
const svg2png = require("svg2png");
const Promise = require('bluebird');
Promise.promisifyAll(fs);
const textToSVG = TextToSVG.loadSync('fonts/文泉驿微米黑.ttf');
const sourceImg = images('./i/webwxgetmsgimg.jpg');
const sWidth = sourceImg.width();
const sHeight = sourceImg.height();
const svg1 = textToSVG.getSVG('魏长青-人人讲App', {
 x: 0,
 y: 0,
 fontSize: 24,
 anchor: 'top',
});
const svg2 = textToSVG.getSVG('邀请您参加', {
 x: 0,
 y: 0,
 fontSize: 16,
 anchor: 'top',
});
const svg3 = textToSVG.getSVG('人人讲课程', {
 x: 0,
 y: 0,
 fontSize: 32,
 anchor: 'top',
});
Promise.coroutine(function* generateInvitationCard() {
 const targetImg1Path = './i/1.png';
 const targetImg2Path = './i/2.png';
 const targetImg3Path = './i/3.png';
 const targetImg4Path = './i/qrcode.jpg';
 const [buffer1, buffer2, buffer3] = yield Promise.all([
  svg2png(svg1),
  svg2png(svg2),
 svg2png(svg3),
 ]);
 yield Promise.all([
  fs.writeFileAsync(targetImg1Path, buffer1),
  fs.writeFileAsync(targetImg2Path, buffer2),
  fs.writeFileAsync(targetImg3Path, buffer3),
 ]);
 const target1Img = images(targetImg1Path);
 const t1Width = target1Img.width();
 const t1Height = target1Img.height();
 const offsetX1 = (sWidth - t1Width) / 2;
 const offsetY1 = 200;
 const target2Img = images(targetImg2Path);
 const t2Width = target2Img.width();
 const t2Height = target2Img.height();
 const offsetX2 = (sWidth - t2Width) / 2;
 const offsetY2 = 240;
 const target3Img = images(targetImg3Path);
 const t3Width = target3Img.width();
 const t3Height = target3Img.height();
 const offsetX3 = (sWidth - t3Width) / 2;
 const offsetY3 = 270;
 const target4Img = images(targetImg4Path);
 const t4Width = target4Img.width();
 const t4Height = target4Img.height();
 const offsetX4 = (sWidth - t4Width) / 2;
 const offsetY4 = 400;
 images(sourceImg)
 .draw(target1Img, offsetX1, offsetY1)
 .draw(target2Img, offsetX2, offsetY2)
 .draw(target3Img, offsetX3, offsetY3)
 .draw(target4Img, offsetX4, offsetY4)
 .save('./i/card.png', { quality : 90 });
})().catch(e => console.error(e));

Precautions

text-to-svg needs the support of Chinese fonts, otherwise the Chinese will be garbled.

It only took more than 500 milliseconds to execute it once on my broken computer. I feel it is enough. I hope to share it to give everyone a reference.                                         ​​​​​​

I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the php Chinese website!

Recommended reading:

Regular expression application in JS

typeof and type judgment in JS (with code)

How does JS detect scripts in the browser

The above is the detailed content of Node operates text to generate images. For more information, please follow other related articles on the PHP Chinese website!