Some lines of text (not all) look blurry


I was trying out Atom today, and I’m running into issues with text rendering. Currently I’m on an Windows 7 machine.

My problem is that when I open a file, the text is blurry for a few lines, then clear for a few lines, then blurry for a few lines, then clear for a few lines. It does this about 3 or 4 times down the length of the page.

Does anyone know what could cause something like this and how to fix it?


Could you give the following information?

  • Which version of Atom are you using?
  • Which themes (syntax and UI) are you using?
  • Can you reproduce the issue after completely exiting Atom and restarting using atom --safe?


That would say to me that the text pixels are a different frequency (pixel spacing) than the screen pixels. So they are “beating” with each other. That is a kind of aliasing. Sub-pixel anti-aliasing would probably fix that. I don’t remember how to turn that on and off in Atom. I know that when using a graphics accelerator there is no sub-pixel anti-aliasing.

  • Using Atom 1.0.0.
  • Using Windows 7.
  • The effect seems to happen on both of my monitors:
  • Primary monitor is 1920 x 1200 resolution.
  • Secondary monitor is 1280 x 1024 resolution.
  • Using One Light for both UI Theme and Syntax Theme, but it also happens if I use Atom Light on both.
  • Running atom --safe didn’t make any difference (still has the same alternating blurry).


Can you post a screen shot of what it looks like?


It’s odd because I filled a page with the letter “a,” and everything looked the same (blurry).

(sorry, only one image per post…)


Then I filled the page with “0” and only the top looked blurry.


Then I look at my original file, and I see the blurring is alternating every few lines.

I’m having trouble now telling whether some of it is an optical illusion, but on my first picture I am pretty sure there is something going on. Overall though, the text in the editor and tabs doesn’t look great. I can’t exactly place what it is, but just seems weird to look at.


I’m not seeing it coming through on the screenshots. Everything looks pretty uniform to me. Though I don’t have the sharpest eyes … so perhaps I’m missing something.


I zoomed in on a place where I thought the difference was most visible. I thought that line #34 looked the “best” and that line #37 looked “blurry”.

It is odd when you zoom in, because it seems like the blurry lines are only shades of gray, while the sharp looking lines have some colors to them (blues, reds, browns, etc.).


This is a great demonstration of the difference between subpixel antialiasing and non-subpixel antialiasing :smile: Lines 34-36 are subpixel antialiased. Line 37 is not. This is perfect, thanks!

@as_cii is there any more information that would be helpful for debugging this?


I opened a bug for this on github. There was another bug about subpixel antialiasing, but it seemed to either be that subpixel antialiasing was either all on, or all off.