Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Error disabling text font antialias #2411

Open
System25 opened this issue Jul 21, 2024 · 1 comment
Open

Error disabling text font antialias #2411

System25 opened this issue Jul 21, 2024 · 1 comment

Comments

@System25
Copy link

Issue

The text font antialias is not properly disabled.

When I run:
convert -size 320x100 xc:white -font Arial -pointsize 12 \ +antialias -annotate +28.5+68.5 'Lorem ipsum' font_tile.png

I get the following image:
font_tile

But, when I try to create the same thing with NodeJS-canvas, I get the following image:
image

I believe that you need to set the text antialias to none at font level with "cairo_font_options_set_antialias":
https://github.com/ImageMagick/ImageMagick/blob/42c30be7ef6a5d272d2a21dedce23f5023cb5723/coders/pango.c#L233

I also tried disabling the antialias at font level by following: https://wiki.archlinux.org/title/Font_configuration/Examples/No_anti-aliasing but that is also not good:
no_antialias

Steps to Reproduce

import { createCanvas } from 'canvas';
import * as fs from 'fs';

const canvas = createCanvas(320, 100);
const ctx = canvas.getContext('2d');

ctx.antialias = 'none';
ctx.imageSmoothingEnabled = false;

ctx.fillStyle = '#FFFFFF';
ctx.fillRect(0, 0, 320, 100);

ctx.fillStyle = '#000000';
ctx.strokeStyle = '#000000';
ctx.font = '12px Arial';

ctx.fillText('Lorem ipsum', 28.5, 68.5);
const buffer = canvas.toBuffer("image/png");
fs.writeFileSync("./image.png", buffer);    

Your Environment

  • Version of node-canvas 2.11.2
  • Environment Ubuntu 22.04.4 LTS
@System25
Copy link
Author

Hi, I manage to print the text right.
You need ctx.textDrawingMode = 'glyph' and disabling the antialias at font level by following: https://wiki.archlinux.org/title/Font_configuration/Examples/No_anti-aliasing

Anyways, it would be really cool if you could disable the antialias by programming.

Thank you very much!

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
None yet
Projects
None yet
Development

No branches or pull requests

1 participant