Formula Editor in GNU Emacs

 

 


Here's a simple formula editor using SVG for quick note taking in GNU Emacs. Presently, it's a single line editor. You can use arrow keys to move around, Shift+arrow keys for selection and backspace for deleting characters. Use Ctrl + x prefix for special actions like grouping (g), fractions (f) and exponents (e).

(require 'formula)
 
M-x formula-mode

Code:

https://gitlab.com/atamariya/emacs/-/blob/dev/lisp/svg.el
https://gitlab.com/atamariya/emacs/-/blob/dev/lisp/formula.el
 

How it works?

In the video, an event loop is started in the scratch buffer. All the edit operations update text and text property in a temporary buffer, say a.txt. Based on this information, in-memory SVG DOM is updated. Ultimately, the display engine updates the view with this SVG image.

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