Automattic/node-canvas

drwaImage with scale or crop render very blur when export pdf file

オープン

#1,822 opened on 2021/06/03

 (4 件のコメント) (0 件のリアクション) (0 人の担当者)JavaScript (1,195 件のフォーク)batch import
BugGood first issueHelp wanted

Repository metrics

Stars
 (10,689 個のスター)
PR merge metrics
 (PR metrics pending)

説明

drwaImage with scale or crop render very blur.

Here is result PDF

This is preview with 200%:

preview with 200%

I wite a demo for show my problem for export PDF.

const exportPdf = async () => {
  const { createCanvas, loadImage } = require('canvas');
  const fs = require('fs');
  const path = require('path')
  let canvasWidth = 200;
  let canvasHeight = 200;
  const canvas = createCanvas(canvasWidth, canvasHeight, 'pdf');
  const ctx = canvas.getContext('2d');
  // image is a 800 x 800 px png 
  const imgUrl = "http://capcium.com/wp-content/themes/capcium/dist/images/-placeholders/img-example-square.png" 
  let img = await loadImage(imgUrl);
  const padding = 100;

  ctx.scale(0.1, 0.1)
  // draw origin image
  ctx.drawImage(img, padding, padding);
  // draw image with scale
  ctx.drawImage(img, img.width + padding * 2, padding, img.width - 1, img.height - 1);
  // draw image with crop
  ctx.drawImage(img, 0, 0, img.width - 1, img.height - 1, padding, img.height + padding * 2, img.width, img.height);
  
  const outPath = path.join(__dirname, `./output_${+new Date()}.pdf`)
  canvas.createPDFStream().pipe(fs.createWriteStream(outPath));
  console.log('end')
}

exportPdf()

コントリビューターガイド