Programming Leftovers

posted by Roy Schestowitz on Nov 07, 2025

• Serge Zaitsev ☛ By the power of grayscale!

  When people talk about computer vision, they usually think of OpenCV or deep neural networks like YOLO. But in most cases, doing computer vision implies understanding of the core algorithms, so you can use or adapt them for your own needs.

  I wanted to see how far I could go by stripping computer vision down to the bare minimum: only grayscale 8-bit images, no fancy data structures, plain old C, some byte arrays and a single header file. After all, an image is just a rectangle of numbers, right?

• Swift Programming Language ☛ Swift on FreeBSD Preview

  We have been hard at work to bring the Swift toolchain to FreeBSD. A preview Swift bundle for FreeBSD 14.3+ is available at https://download.swift.org/tmp-ci-nightly/development/freebsd-14_ci_latest.tar.gz. The bundle contains a Swift development compiler and Swift runtimes needed for compiling Swift programs on, and for, FreeBSD 14 on x86_64 machines.

• Python

  • Robotic Systems LLC ☛ tview python console

    The tview graphical monitoring application has been getting a lot of work lately. First was support for enumerating controllers by UUID, then monitoring faults and graphically highlighting them and then decoding textual values for fault codes. I’m excited to announce yet another improvement for tview, this one on the larger side: an interactive python REPL (read-evaluate-print-loop)! Available now in pypi moteus-gui v0.3.93.

• R / R-Script

  • Rlang ☛ Faking plotly’s ‘y unified’ tooltip in ggiraph

    We settled on ggiraph as our interactive visualisation package for a new Shiny dashboard. The goal was simple: capture the Y-axis value, grouped by the X-axis to display in a tooltip when a user hovers over an element. I’ve used plotly before, and it has a handy “y unified” argument that does this perfectly (see plotly reference). The hitch? ggiraph doesn’t offer that option.

    The Solution: This little snag is now sorted! I’m writing this blog post to solidify the lesson for myself and hopefully save others the headache if they run into the same problem. Let’s start with the setup.

  • Rlang ☛ Dimension reduction

    According to Wikipedia, Uniform manifold approximation and projection (UMAP) "is a nonlinear dimensionality reduction technique". It will allow us to project many dimensions (well, only 3 in this example) onto a 2D plane.

  • Rlang ☛ Graceful Internet Packages

    Join us for our next Community Call, “Graceful Internet Packages,” featuring Matthias, Tan, and Salix. In this session, we’ll explore how to design and maintain R packages that interact with online data sources. Our speakers will share practical lessons, examples, and best practices to help R package developers create reliable packages.

• Java/Golang

  • Frank Delporte ☛ Links from the JFall talk 'Foreign Function & Memory (FFM) API on Raspberry Pi'

    The Foreign Function & Memory (FFM) API, finalized in Java 22, promised to make such integrations with native code a lot easier. With Java reaching a new Long Term Support version, it’s time to bump the Pi4J project to Java 25 and make full use of FFM!

    In this talk, you’ll learn how this FFM implementation is much easier to support and achieves high performance due to less memory copying and less interop code. It will also help improve the Pi4J project: fewer dependencies, a smaller JAR footprint, support for more protocols, and compatibility with more SoCs, among other benefits.

• Rust

  • Rust Weekly Updates ☛ This Week In Rust: This Week in Rust 624

    Hello and welcome to another issue of This Week in Rust!