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Comment by JepZ | Hacker News Reader

If I understand this correctly Xi and Alacritty are both using OpenGL to do the rendering and recently I heard that Rust supports compiling to Web Assembly.

Sounds as if it should be easy to port those apps to the browser world (WebGL + Web Assembly)? Does anybody know of any plans to do just that?

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"Easy" is not the right word for this, but it's possible. One challenge is that browsers don't export an interface for "shaping". For Latin script, that means kerning and ligatures, and for complex scripts, it means being able to render it correctly at all. Currently, alacritty doesn't really deal with this, but xi-mac does, using the interfaces provided by Core Text.

That's where pathfinder [1] comes in, as the fastest font rasterizer, utilizing the GPU and built in rust. (not affiliated). Ok maybe I'm overselling just a little but it's exciting!

[1]: https://github.com/pcwalton/pathfinder

Thanks for the kind words :) But Pathfinder doesn't do shaping.

Ah, thanks for the clarification. It seems I need to do a bit more research before I advocate others projects, sorry about that. :)

Figma (a UI design tool written in C++ compiled to JS using emscripten) talked about this briefly in their tech blog. They compiled FreeType to JS for rendering fonts to bitmaps: https://blog.figma.com/building-a-professional-design-tool-o...

Figma actually only uses FreeType for parsing fonts (fonts are rendered using a custom WebGL-based renderer). Figma uses HarfBuzz for text shaping, which is easy to run on the web with emscripten: https://github.com/harfbuzz/harfbuzz.

Just found https://github.com/acheronfail/xi-electron but actually I was more thinking of running the whole editor in the browser, not just the frontend.

Do any of the latency advantages of Xi carry over if you wrap it all up in Electron? The Electron editors do pretty badly on this front [1].

[1] https://pavelfatin.com/typing-with-pleasure/

I haven't started measuring it yet, but plan to. The idea of keeping the UI component light and doing all the heavy lifting in the core _might_ work well in Electron (as opposed to having all the logic in JS), and xi-electron is a good testbed for exploring that.

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