martin-t / visualizr

A tool for visualizing the internal representation of objects in the R language

Visualizr

A tool for visualizing the internal representation of objects in the R language

TODO screenshot

The code is split into 2 parts:

• Inspectr - an R package which reads the internals of R objects and sends them to visualizr
• Visualizr - a GUI which draws the internals and relationships between objects

Dependencies

• Rust
• Visualizr uses the macroquad game engine - if you're on Linux, you need to install its dependencies.
• Inspectr uses rextendr so you need to install it. The devtools package is also recommended.

Usage

Currently you need to compile this project from source to use it.

• Compile and run visualizr - cargo run in the project's root.

• Run R in inspectr/

  • Compile and load inspectr: rextendr::document() ; devtools::load_all()
  • Now the visualize function should be available - use it on arbitrary R objects and visualizr will draw them.

Development

Misc note: rextendr::document() (sometimes?) doesn't notice when a dependency changes - you have to make a change in inspectr directly for commonr/bindingsr to be recompiled.

Lessons Learned

• There are 2 libs for interfacing with R: rextendr and cargo-framework. Rextendr appears to be higher level while cargo-framework appears to expose raw SEXPs. In reality:
  • Cargo-framework has verious issues:
    • Doesn't handle nightly (fails to parse version string, who knows what other issues there are).
    • Some functions e.g. run fail even with stable.
    • You need to manually delete the .so file to trigger a recompile (I only tested on linux).
    • For some inexplicable reason it copies the entire source code of its sublibs into your source code.
    • Maybe I was holding it wrong but it seemed to (also?) create a new project in a different directory than I specified, twice.
  • Rextendr is much more mature and you can access raw SEXPs from it as well. I recommend using rextendr since I can't think of anything where cargo-framework would be better.
  • Rextendr's bindings don't include internal headers but it's trivial to create your own bindings with #define USE_RINTERNALS and use those.
    • You can cast between the SEXP type from the 2 libs.
• All Rust GUI libs are awful. I wanted something that offers draggable boxes for SEXPs and an easy way to draw lines between them.
  • I couldn't figure out how to get the position of a GUI element in egui. It is possible, https://github.com/setzer22/egui_node_graph does it, it's just a mess to figure out and i gave up.
  • Macroquad's GUI (megaui) is much easier to figure out but has various small but annoying issues: selecting or copying text randomly doesdn't work; if there's too much text, it all disappears until the user scrolls; it reports the wrong mouse position until it moves, ...
  • I don't have a good solution here, macroquad is probably the lesser evil.

License

AGPL-v3 or newer