Claude Code: Now in Beta in Zed

My guess: their shaders or text rendering don't account for sub-pixel anti-aliasing, which is critical to getting decent text rendering on low pixel density displays.

If they'd used Skia (which is what Electron and Chromium use), they would've got this for free. Instead they tried to reinvent the world and didn't realise how big the world was.

I love how we just reinvent the wheel again, and again, and again, and again...

MacOS native apps have had great sub-pixel rendering all along, but I guess since we have to develop everything in Electron now it's time to reimplement all the exiting functionality.

> MacOS native apps have had great sub-pixel rendering all along

Apple removed subpixel anti-aliasing in Mojave, seven years ago, because it's not necessary on the HiDPI/Retina displays they ship as standard. They still do greyscale anti-aliasing but that's not the same thing as subpixel.

Discussion from the time: https://news.ycombinator.com/item?id=17476873

> because it's not necessary on the HiDPI/Retina displays they ship as standard.

I disagree. Subpixel anti-aliasing triples the available horizontal resolution, and makes text crisper. The algorithms are known and regardless of the density it should always be applied to text and vector graphics elements.

The RGB stripe layout is so useful that OLED manufacturers are moving to it in 2026, away from the long-derided PenTile where magenta/green fringing is seen even on the densest displays.

In fact rendering on macOS is completely broken, and I don't know how people stand by it. At any scaling factor selected that is not a perfect factor of the actual hardware resolution (the 'looks like' value in Settings), the final framebuffer is scaled and interpolated to the display resolution, and everything is noticeably more blurry.

Windows has had some form of hardware-independent rendering since Windows 7, and proper pixel density control arrived in Windows 8.

Subpixel rendering is effective but it's also a massive pain in the ass to maintain, especially if you want to take full advantage of the GPU. Microsoft has kept it around for much longer but even they are steadily moving away, bits and pieces of the Win11 UI render with greyscale AA regardless of system settings because their newer GUI toolkits don't even attempt to support subpixel fonts.

That said, for something like a text editor where fonts are central the entire application and the worst subpixel edge cases like animation are unlikely to come up, it's maybe not unreasonable to ask them to go the extra mile. It's going to be a sticking point on Windows and Linux for a long time if they don't.

- As mentioned, macOS removed subpixel anti aliasing a while ago

- Zed is not an electron app

- In the linked issue you can see that this issue does not exist in Electron.

As far as I can figure out, the root issue is even simpler than that. Their hinter is broken. The edges of characters aren't aligned with the pixel grid, so there's lots of fuzzy/blurry looking text.