[dcalacci]

>So here's my idea for a great emacs-based document editor: markdown with inline math previews coupled with a full live preview to the side. All the necessary modes for this already exist

So org-mode has you covered there, basically. Org isn't markdown, but it's close (and full of tons of note-taking features), and you can do inline latex with live preview in org-mode. I use it for notes all the time.

[gcr]

> inline latex with live preview in org-mode

This certainly isn't the default. Could you elaborate more on how you set this up?

Edit: Found my answer. M-x org-preview-latex-fragment, which is bound to C-c C-x C-l.

Edit 2: Hey look, you can get tikz working! Evaluate or add this to your .emacs:

    (add-to-list 'org-latex-packages-alist '("" "tikz" t))
    (setq org-latex-create-formula-image-program 'imagemagick)

Then, type the following into an Org-mode document and press C-c C-x C-l:

    \begin{tikzpicture}[scale=0.1]
    \draw[fill=green] (3,0) circle (9);
    \draw[fill=orange] (1,0) circle (5);
    \draw[fill=blue] (0,0) circle (3);

\end{tikzpicture}