The best app I know of for this is Monodraw (https://monodraw.helftone.com/)
I've searched for something like this before. I was looking to create diagrams in a markdown file. I found mermaid was a better option in that specific case. https://mermaid-js.github.io/mermaid/#/
Can it reverse engineer a diagram?
It would be kinda neat to store only the output in, say, a readme file or whatever, and not have to have a second file with the input.
This looks really cool. To me personally graphs look the best with "ASCII only" option turned on.
I feel like this is something I have been looking for for years.
Is this from (2018)?
Nice. I've seen similar tools for small subsets of what this is doing, but it'll be useful to have a set of utilities like this done well in one place.
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One thing I've wanted for ages (and might like to write but will likely never find time) is something that does drawio/viso-like diagram manipulation but works in ASCII/Unicode, defaults to text output, and maintains limits (forcing the grid granularity and sufficient spacing for connectors) to make that practical even if offering a more “graphical” output and edit experience.
I've seen a few tools that let you draw diagrams in ASCII/unicode but they have all been more akin to paint than drawio, in that you can't edit objects or move them around after placing, and have connectors & such reflow.
It would be useful for dropping diagrams into otherwise text-only media (flow and table diagrams in readme files, adding table diagrams on dba.stackoverflow without needing to instead link to a graphic or edit more by hand, ...) while allowing a prettier output (as SVG or a bitmap) for where that is relevant. If anyone knows of such a tool I've missed that they can point me to, or wants to go away and write one for me, please do!