Regarding Font Rendering Abnormalities

[jxh150535011]

In a Node.js environment, when I keep the default setting disableFontFace: true, some fonts display as blank with warnings about missing font paths. To fix this, I set disableFontFace: false. However, this causes other content (such as red text) to display as garbled characters. How can I resolve this issue?

Note:

With disableFontFace: true, the red text renders correctly, but black date fields appear blank.

With disableFontFace: false, the dates show properly, but the red text becomes garbled.

[calixteman]

Without the pdf file, it's pretty hard (impossible ?) to say something.
Maybe some fonts aren't embedded and it's why disableFontFace:true is failing but I'm not sure of that.

[jxh150535011]

Without the pdf file, it's pretty hard (impossible ?) to say something. Maybe some fonts aren't embedded and it's why disableFontFace:true is failing but I'm not sure of that.

Ignoring the issue with disableFontFace: true for now, I think it's fine to keep it as false. What I'm concerned about now is the issue with messy characters. Because fontChar displays messy characters. To avoid displaying messy characters, we can simply change the returned unicode to fontChar and the characters will display normally. However, it's evident that the font style is lost.

For example, although it is displayed below, the font is incorrect, because the correct font is shown in the last picture

[jxh150535011]

Without the pdf file, it's pretty hard (impossible ?) to say something. Maybe some fonts aren't embedded and it's why disableFontFace:true is failing but I'm not sure of that.

I forgot to add that it works normally on the web, but the fonts cannot be displayed properly only in the Node.js environment. It should be due to the lack of my local fonts in the Node.js environment. And I don't know how to add these fonts
I tried to register a font with the canvas, but obviously it failed because I didn't know what the font was

canvas = require('canvas');
const fontFile = resolve('node_modules/pdfjs-dist/standard_fonts/LiberationSans-Regular.ttf');
canvas.registerFont(fontFile, { family: 'serif' });
canvas.registerFont(fontFile, { family: 'SimSun' });

[jxh150535011]

I think I've found a solution, but it's a bit invasive. I don't know the specific principle, but it works

First, set disableFontFace to true. This will enable the normal display of fonts in "red". For characters with missing fonts, modify the code

pdfjs-dist/legacy/build/pdf.mjs

if (simpleFillText && !accent) { ctx.fillText(character, scaledX, scaledY);
修改为:
if (!font.attached && !accent) { ctx.fillText(character, scaledX, scaledY);