This post is devoted to a collection of tricks to produce technical graphs.
It could be awesome if TeXmacs has a way to programmatically build sketches like tikz do (perhapswith a GUI interface also associated to it).
I’ve seen a note on embedding graphics composed with Scheme into documents.
You can look at the Graphs plugin to generate programmatically graphs with other tools like TikZ, asymptote, etc… Also in the graphics editor try the ‘!’ key 
You can generate whatever content you want from scheme, also graphics. But we do not yet have a nice facility to do that. That said we have plugins for many common systems, including geogebra, and as I said asymtptote, gnuplot, TikZ, FeynMF, … and you can always generate pictures in Python with matplotlib. What is missing is a way to generate programmatically vector picture and then edit them in the graphics editor (unless you generate them via Scheme). But you can always import a picture and then do “Ink here” to draw over it within the graphics editor.
Ipe is interesting and seems relatively complex graphics editor. One could imagine to have a tool to edit very comple images in Ipe and then importing in TeXmacs (the Ipe format is XML, so easy to convert to our document format). Wrt. to LateXDraw the examples I see on the web are relatively easy to do within our graphics editor. When things become very complex it would anyway be necessary to switch to tools like Inkscape.
I should have been clearer in my post, the graph plugin with Tikz support is really excellent. I should have mentioned it, but I was actually thinking more about combining the possibility of “programming” drawings like Tikz can and also modifying them with a gui.
The support of tikz is very interesting for the compatibility with latex but should not in fact prevent the possibility of thinking of other solutions.
@mgubi As you mentioned we can always import a picture and then do “Ink here” to draw over it within the graphics editor, like this:
Which one is which between Tikz and Texmacs drawings ?
(the left top is texmacs, the others TikZ?) I agree indeed that we are lacking a reasonably flexible way to programmatically produce graphics within TeXmacs. One would have to code an equivalent of TikZ or MetaPost, or maybe more realistically, have a way to convert the output of programs like asymtptote or MetaPost into TeXmacs graphics. I still do not see what is a good way to proceed. Scheme is Turing complete so maybe we could just take inspiration from Racket for a flexible graphics library for TeXmacs.
Can I use the screenshot for TeXmacs twitter account? It would be nicer if the cursor would be inside the graphics editor so that we see the functionality active.
You both win, congrats !
Indeed, the fonts are the right indices … Well done the Sherlocks 
Here are other screenshots (zoom, drawings with grid or without, full page) to choose from in the hope you’ll find one or two better suited for posting to twitter:
Do not hesitate to ask me something different if you prefer.
That’s great. Thanks.
What (color) theme is this? Is it available somewhere?
I use the exam style file and modified just a tad.
I’ve planned to share this template when I’m ok with it, but you will find a first version here.
I was indeed thinking you can contribute this for tm-forge/examples. It does not have to be a fully featured style package. Examples on how to hack the existing features are also ok.
I’ll try to put this on tm-forge/examples but at present time I only modify some 2 or 3 basic macros and don’t render the exam style justice because I don’t use the nice question/answer features of the exam style. Anyway the example may inspire somebody who knows …
I do not think that examples have to be necessary complex. They showcase the various possible uses and that one can produce nice documents. Also you might want to include the logo image in the source so that the document becomes self-sufficient. (you can do it with the green up arrow in the focus bar of the image tag).
Just made a pull request on tm-forge.
It might be as well better to turn this into a Wiki.
