Indholdsfortegnelse for August 2020 i Linux Format

Jonni Bidwell It’s hard to properly decouple from Google on mobile. But you can start the journey with the F-Droid app store, where you’ll find builds of Firefox Focus, Telegram and Signal. And if you really need something from the Play store, you can use the slightly sneaky Aurora Store. Nick Peers Ventoy is a brilliant boot disk tool that enables you to place all your bootable media (as ISO files) on a single flash drive, then switch between them as required at startup. At last, one boot disk to rule them all! Les Pounder I regularly use my Android phone for work and recently I found out about a tool called scrcpy, which enables me to use my phone from my Ubuntu machine. So now I can answer calls,…

“With only free software, a Mali G31 chip can now run Wayland compositors with zero-copy graphics, including GNOME 3. It can run every scene in glmark2-es2, and 3D games like Neverball can be played. In addition, it can support hardware-accelerated video players mpv and Kodi. Since we began work on Bifrost, fellow Collaboran Tomeu Vizoso and I have progressed from stubbing out the new compiler and command stream in March to running real programs by May. Driven by a reverse-engineering effort in tandem with the free software community, we’re confident that against proprietary blobs and downstream hacks, open source software will prevail. We plan to improve Bifrost’s coverage of OpenGL ES 2.0 to support more 3D games, now that the basic accelerated desktop is working. We also plan to improve…

Sean Kelly has begun to post enablement patches for CXL (Compute eXpress Link), a new interconnect layered over PCI designed for point-to-point attachment of workload accelerators, as well as expansion memories. CXL is similar to specs such as CCIX, CAPI and NV-Link. It has the weight of Intel behind it and is expected to gain traction. Linux uses a “page cache” structure to keep copies of filesystem data in memory. When you open a file or edit a document, underlying reads and writes to and from secondary storage go via the page cache to improve performance by keeping recently used data around. Matthew Wilcox posted “Large pages in the page cache” which aims to reduce the number of “pages” that need to be tracked by not requiring specific sizes, aiming…

Seven deadly sins  Q I just converted a laptop with Windows 7 to Linux Mint 19.2 to bring new life to it. In the process I substituted the old internal HDD with a new SSD and installed Linux as the only OS of the disk. I then inserted the old Windows 7 disk into a USB external box to occasionally run applications not available on Linux. Basically I need the official iTunes application to manage paid songs downloaded for my iPhone. I tried sudo update-grub , but it’s not enough – the external disk never appears in the Grub menu at startup. Note that the Windows 7 OS on the HDD is fully functional (I can boot it if I change the boot priority from BIOS). Also, if I run Mint,…

Announced in 2017 as a crowdfunder that was impressively supported, Purism’s Librem 5 is a smartphone take on the Librem laptops. The device is equipped with kill switches and other privacy-enhancing measures, and has been positioned as the company’s solution to forced obsolescence, digital surveillance and the lack of a genuine Linux smartphone. The Librem 5 was released in late 2019 and was shipped to some but not all of its early supporters, and those who received the smartphone noted it sported fewer features than originally advertised. Review devices were suspicious by their absence, until six months later when we can finally examine the Librem 5 phone. Weighing in at 230g, the Librem 5 is a charcoal grey slab containing a quad-core processor, 3GB of RAM, and 32GB of eMMC…

We tried each file manager in Gnome (running on Ubuntu 20.04) and KDE Plasma running on an up-to-date Arch Linux. You may not want to install Krusader on Gnome, and you may not want to use a terminal file manager at all. But we did a variety of tasks in all of these settings. Searching on our disorganised drives for files, connecting to network servers we didn’t know were still working in the Future Towers basement… all manner of things that only foolhardy file wranglers would dare. We also hunted around for common gripes and remedies, had a long look at Github issues for each project, and even prepared a short quiz on each candidate’s keyboard shortcuts (which we duly failed). Of course, we also did all of the everyday…

If you want a lightweight GUI file manager that you can use anywhere, then Xfce’s Thunar is perfectly fine. There’s also the popular lightweight fork, PCManFM, or the even lighter SpaceFM – both are worth a closer look. If you want to be even more adventurous than Ranger, try nnn (see page 54) . It’s written in C and blazingly fast thanks to its use of low-level functions. Nnn uses contexts (think tabs that remember things statefully). It doesn’t exactly have built-in panels, but that’s by design. A terminal multiplexer will remedy this, and look very stylish too. We considered including a few others, but they haven’t been updated for a long time. The electron-based JumpFM got a lot of people excited a few years back, for example. Finally, it’s…

Don’t worry if you think something’s not right with a particular Linux distribution. You’re entitled to a full refund after all. Only kidding. In 2012 even Linus himself raged at OpenSUSE developers when he discovered that adding a printer (on his daughter’s laptop) required the root password. Sometimes there are reasons why things are that way (in 2012 there wasn’t the notion of a privileged local user; it’s handled by systemd these days), sometimes it’s a genuine bug, and sometimes you’re just using it wrong. These days Linus is generally calmer (except perhaps on the subject of L1D cache flushing), and his recently purchased development machine (a Threadripper 3970X which you can read all about on ZDNet at www.zdnet.com/article/ look-whats-inside-linustorvalds-latest-linux-development-pc) runs Fedora 32. And we’ll talk about that later on.…

So the Raspberry Pi 4 now has an 8GB model. It was supposed to be a birthday surprise this year, but it was delayed by the Coronavirus pandemic. This new release also saw the 2GB model drop in price to $35, and that made the 1GB model pretty much redundant for consumers and it’s no longer being offered for general sale. The 1GB model is still available for industry use, but if you can get the double the RAM for the same money, then it’s no surprise that consumers from all aspects of the community are jumping at the opportunity to purchase a Pi with a better spec. The Pi4 is a decent piece of computing and a serious alternative for light desktop use. Granted, you won’t be editing video…

The new Raspberry Pi High Quality Camera is fantastic. It may cost much more than the standard camera, but it uses interchangeable lenses (bought separately). We can also use old C and CS mount lenses, or other lenses via adaptors. A proper aluminium screw mount provides a solid fitting to secure our camera to a tripod. The new camera connects to all models of Pi with a Camera connector, including later models of the Pi Zero via an adapter cable. It can be controlled using Python, as we did in this tutorial, and it can be used directly via the raspistill and raspivid commands in the Terminal. But what makes the latest camera so different to those before it is that there’s so much manual control. We can alter the…

You’d think after this file management extravaganza of an issue (see Roundup, HotPicks) you’d think we’d have had enough. But no, it seems we’re hell bent on having you organise your files (it’s synchronicity, we plan nothing! –Ed) this month. So listen up. Nnn, or n cubed, bills itself as the fastest file manager ever written. It’s based on Noice, so the name is a recursive acronym for Nnn’s Not Noice. We really liked our terminal offering in the Roundup, Ranger, but nnn takes things to the next level. It’s written in C, and aims to have as small a memory footprint as possible. As a result, it’s pretty minimal and won’t be to everyone’s tastes. Heck, it doesn’t even have a configuration file, so if you want to change…

The ‘fontsize’ property enables you to resize text without making use of Headings styles. The simplest option is to set font sizes in relation to the default body text by choosing ‘smaller’ or ‘larger’. More precise options are available – see www. w3schools.com/cssref/pr_font_ font-size.asp. To improve the readability of your XHTML code, right-click inside the editing pane and choose Reformat HTML>Mend and Prettify Code. This will reformat the code using indents to make it easier to read and follow. The ePub format has been around for a long time, and Sigil supports both ePub 2 and 3 formats (see https:// bit.ly/lfx265-epub-formats for a detailed comparison). Change version via Edit > Preferences > General Settings…

If you want to have many components available while you design a circuit, there are several online solutions. One of them is Upverter (https:// upverter.com). This site acts as a circuit design program with the added advantage of having many components available and updated continually. To get started programming your Arduino in C, find the examples that come with the simavr source code. These cover several scenarios, which makes it ideal for learning the basics of C programming for AVR chips. See https:// github.com/buserror/ simavr/tree/master/ examples. PICSimLab is another simulator, but it only supports the stable version of atmega328. The experimental build supports more chips and boards. https:// github.com/lcgamboa/ picsimlab.…

Welcome to Netdata, software for distributed real-time performance and health monitoring of UNIX machines. Don’t you dare turn that page! A key advantage of Netdata is that it collects all of its metrics without introducing too much load on to the Linux machine that it runs on. In fact, most of the times you’ll forget that Netdata is running on a Linux machine – it’s only after you look at its impressive visualisations that you’ll remember the software is collecting, processing and visualising all these metrics! Another Netdata advantage is that it carries out real-time monitoring, so you can see what’s happening on the Linux machine at that time. Install Netdata using your package manager. On a Debian or Ubuntu Linux system you can install Netdata by executing apt install…

If you don’t like Netdata or if you want to try something else, you can give Grafana (https://grafana.com), Telegraf (www.influxdata.com/time-series-platform/telegraf) and InfluxDB (www.influxdata.com/products/influxdb-overview) a try. Grafana can’t work in isolation – it needs to obtain its data from one or multiple external sources. InfluxDB, which is a time series database, is the most popular data source for Grafana. On the other hand, Telegraf is used for collecting metrics that it stores to InfluxDB. The main difference between Grafana and Netdata is that you’ll have to create your own setup for Grafana to display and visualise data. Issue 259 of Linux Format contains a tutorial on Grafana – have a look at it if you want to know more about Grafana, Telegraf and InfluxDB. Prometheus (https://prometheus.io) is another popular monitoring application…

We might want to make some improvements to take our Pac-Man game to the next level. Consider how we might change the level layout. Perhaps when the player has picked up all the dots, we could load in a second level. We could even make the levels automatically generated, therefore creating an unlimited amount of gameplay. Some other alterations that might bring fun challenges to the game include: change where the player starts, by altering Pac-Man’s spawn location; increase or decrease the number of ghosts in the game for different levels; and make the ghosts faster or slower as the player progresses through the levels. If we really wanted to take things to the next level, we could introduce multiplayer. In the past, Pac-Man games have experimented with different forms…

D3.js (https:// d3js.org) is a low-level JavaScript library, which means that you’ll need to write lots of code even for the simplest of the examples. On the other hand, D3.js gives you absolute control over the output. D3.js works with selectors. In order to do almost everything in D3.js you’ll have to select one or more elements in the DOM (Document Object Model) and modify them according to your will. The d3.select (“body”) call is such a selection that uses the “body” keyword. Learn more about Vega and Vega Lite at: https://vega. github.io and https://github. com/vega/vega, respectively. The Vega Lite documentation can be found at https://vega. github.io/vegalite/docs The Vega docs are located at: https://vega. github.io/vega/ docs. Find sample data sets at: https://github. com/vega/vega-datasets.…

D3.js has a large API and looks complex at first, but it’s really not. This assumption comes from the fact that D3 is not a graphics library but a JavaScript library that can manipulate the DOM tree. Therefore, its core elements are not circles, lines and points but nodes and DOM elements. As a result, its output is not created by putting shares on your screen, but rather by styling and changing the attributes of the elements you want. The other reason that D3 is considered complex is that in order to create a plot using D3.js you’ll need to know lots of other technologies including CSS selectors and properties, SVG and the JavaScript object model. Last, you’ll need to know how to work with JSON in JavaScript to be…

Waiting for Godot Get into gaming the easy way… we kick off building your own game with the open source 2D/3D gaming engine. Develop like a pro! Wondering how to super-charge your coding? We test the best integrated development kits in town. Open source PIC We explore how you can use open source to design, develop and build lightweight projects with PIC chips. Enter the Zen zone! Project management has never been easier than with Zenkit. It’s the ideal way to add order to your life and start relaxing. Contents of future issues subject to change. We might be too busy distro hopping to write anything!…

We’re all quite old here at Linux Format. Effy’s looking forward to retirement, I’m enjoying the fresh and exciting new aches and pains that my joints bring each day, and Jonni’s looking forward to many decades paying off his boat’s mortgage. So we’re all set in our ways. Effy’s been using Mint for an age, I’m happy using Ubuntu and even Jonni doesn’t like updating his install of Arch too often these days. But there’s a new generation of Linux users coming through and they’re looking for new features, new approaches and they’re bringing with them the next-gen of Linux distros. Some of these distros sport cutting-edge technology, while others offer a super-slick user experience. But at their hearts they’re all running the Linux kernel. So this issue we’ve tasked…

Linus Torvalds announced the release of Linux 5.7. The new kernel includes support for thermal pressure monitoring and frequency invariant scheduler accounting. The latest kernel includes “almost 14 thousand non-merge commits...from close to two thousand developers”. Linus occasionally shares small personal updates in his announcement mails. In the past month he noted that for the first time in 15 years his latest desktop machine isn’t Intel-based: “No, I didn’t switch to ARM yet, but I’m now rocking an AMD Threadripper 3970x. My ‘allmodconfig’ test builds are now three times faster than they used to be, which doesn’t matter so much right now during the calming-down period, but I will most definitely notice the upgrade during the next merge window”. Crosstalk vulnerability The latest processor security vulnerability has been announced. SRBDS…

We’d love to try and answer any questions you send to lxf.answers@futurenet.com, no matter what the level. We’ve all been stuck before, so don’t be shy. However, we’re only human (although many suspect Jonni is an out of control Roomba), so it’s important that you include as much information as you can. If something works on one distro but not another, then tell us. If you get an error message, please tell us the exact message and precisely what you did to invoke it. If you have, or suspect, a hardware problem, let us know about the hardware. Consider installing hardinfo or lshw. These programs list the hardware on your machine, so send us their output. If you’re unwilling, or unable, to install these, run the following commands in a…

Since it’s KDE’s flagship file manager, Dolphin is meant to do everything it needs to without modification. Still, you can find various service menus in the KDE store, which are easy enough to install. Common applications will integrate nicely anyway, and lots of what the store extension services do would be better done from the servicing application. Still, each to their own. Likewise, there are a few add-ons for Krusader in the store, but most of them seemed to be rather old. Midnight Commander doesn’t have much in the way of easy extensions. But you can program your own macros using variables and even prompt for user input. There’s a so-called extension file, which you can customise in the .config/mc directory, but its purpose is to define custom applications for…

Cast your mind back 15 years, to that pre-credit crunch optimism of the mid-2000s. Windows users were appalled by Windows Vista, and this new Ubuntu operating system was claiming that it could displace Windows. This, despite being based on Linux (something you needed to have either contributed to yourself or subscribed to an arcane journal such as Linux Format to understand) and thinking that orangey-brown hue was a good desktop colour. Well, Windows may not have been wiped out by Ubuntu. But Linux has developed in leaps and bounds. It’s more useable than ever and key industry players take it much more seriously now. Thanks to Valve and Vulkan, we can play thousands of Windows-only titles on our Linux boxes. More companies than ever are shipping Linux on consumer hardware.…

Amanda Brock is CEO of OpenUK (https://openuk. uk), a new non-profit body focused on promoting Open Technology, but this is a recent appointment in a line of influential positions. She has a CV that includes open source advisory work at the United Nations Technology Innovations Labs, being a European rep for Open Invention Network (the largest defensive patent pool in the world) and being on an Open Projects Advisory for the OASIS Standards Body. She also spent five years as General Counsel for Canonical where she set up the legal function. Part of the reason Amanda is involved in so many projects and initiatives is apparent the moment the VoIP connection kicks in. Even a global pandemic can’t stop Amanda being a connector. She’s someone who enjoys talking to people…

Firefox 75, which is included in Ubuntu 20.04, introduced support for hardware accelerated video decoding and WebGL via VA-API. This support is currently only available if you’re using Wayland, rather than the traditional X11 display server. You’ll also need VA-API set up for your hardware (check the vainfo command), which the dimensions of this box preclude us from helping you with. This is all still considered experimental, so don’t be too surprised if it doesn’t work, or you have to cherry pick options. Start Firefox from a terminal with MOZ_ENABLE_WAYLAND=1 firefox . Then head to about:support and check that the Window Protocol (in the Graphics section) is indeed set to Wayland. Good. Either OpenGL or WebRender (even more experimental) compositing should be enabled, so scroll back to the start of…

Despite its size and low power, the Raspberry Pi has proven to be a useful addition to any game streaming set up. While it won’t run modern games, it can stream them from a PC with Steam or Parsec. All you need is the PC or laptop (or custom game server) running on the same network as the Raspberry Pi and a game controller or two connected. The same is true with Google Stadia. You might have heard about Google’s game streaming platform, which pre-launched in November 2019 ahead of full launch in 2020. It enables the streaming of AAA games to your desktop PC computer, potentially with just a subscription. Want to stream games to TV? You can, using a Google Chromecast Ultra and dedicated wireless game controller (see…

Nnn is tiny but highly extensible. There are several plugins available in the Git repo (check out the list at https://github.com/jarun/nnn/tree/master/plugins, which also shows their dependencies), and even a script to install them easily. You can run this script directly (but even though it runs as your user it’s good practice to check it first) with curl -Ls https://raw.githubusercontent.com/jarun/nnn/master/plugins/getplugs | sh This will install all the plugins in ~/.config/nnn/plugins. To use them we list them in the NNN_PLUG environment variable, together with a hotkey to invoke them. For example if you’ve got the mediainfo tool installed ( sudo apt install mediainfo ), invoke the mediainf plugin (which requires $PAGER to be set too) with: export PAGER=less export NNN_PLUG='m:mediainf’ then start nnn as normal. Now find a media file, hit ;…

VECTOR DRAWING Inkscape Version: 1.0 Web: https://inkscape.org Were you to ask an open source user to name three drawing packages, the third one they’d mention would very likely be Inkscape, after GIMP and Krita. However, it’s the only vector graphics package on that list. That makes Inkscape hugely important to the open source world and after 16 years of development it’s just turned the big 1.0. Getting hold of the latest build of Inkscape is about as easy as it comes. Inkscape offers builds in both Flatpak and Snap formats, which are now both widely supported. For Ubuntu users there’s a PPA that you can latch on to and obtain updates from, usingsudo add-apt-repository ppa:inkscape.dev/stablesudo apt updatesudo apt install inkscape The 1.0 release brings with it a host of low-levelperformance…

The gpsim software can also simulate your projects. If you can look past its slightly crude interface, it’s possible to design a breadboard and simulate what it does. You may have a problem finding your specific components since it’s still in development. It’s developed with support for modules to describe the circuits. This should give much opportunity to create new chips. Despite the initial learning curve, this program has a lot of potential. When you run this program, it starts with a text interface, this interface is open even when you run the graphical user interface. Currently, the software focuses on the states of registers inside the chip and traces any faults in your code. Using it for a small hobby project isn’t yet worth the effort, but it is…

Find out more about netdata at www.netdata. cloud and the documentation of netdata at https://docs. netdata.cloud . The GitHub repository of netdata is located at https://github. com/netdata/netdata and the netdata Docker image can be found at https:// hub.docker. com/r/netdata/ netdata. Netdata offers support for various backends to archive the collected metrics. A list of supported backends can be found at https://docs. netdata.cloud/ backends. If you need something more advanced and more customisable than Netdata, then consider the BPF/eBPF tracing and observability tools. They can help you analyse CPUs, memory, disks, file systems, networking, programming languages as well as the Linux kernel itself. However, they’re more difficult to learn and don’t automatically generate such pretty visualisations as Netdata!…

Pac-Man is arguably one of the most famous video game characters in the world. First shooting to fame in 1980 with the release of the arcade version, Pac-Man has seen many iterations, remakes and sequels over the years, but nothing compares to the original. It’s a simple premise, really. Pac-Man is a yellow, disk-shaped, mainly feature-less character, who roams around a 2D environment collecting dots. The player has to collect all the dots in the room without being touched by any of the four enemy characters in the form of ghosts. Pinky, Blinky, Inky and Clyde are brightly coloured to stand out against the black background, being pink, red, cyan and orange, respectively. Pac-Man must avoid the ghosts and collect all the dots to progress to the next level. Pac-Man…

Both Vega and Vega Lite are written in JavaScript and both of them implement a grammar that offers a convenient way for creating graphs and plots, which also means that you should follow certain rules and use certain keywords on your Vega and Vega Lite files. Vega Lite is a grammar that’s based on Vega just like LaTeX is based on TeX. The main advantage you get from using Vega Lite is that you need to write less code than Vega. Both grammars are better for visualising tabular data and can be used as a file format for creating and sharing data and visualisations. Using a grammar for visualisation has both advantages and disadvantages. The biggest disadvantage is that you’ll have to learn the rules and the restrictions of that…

“Every once in a while, you see a discussion that blows up into one of those head-scratching moments. One where you ask yourself, “What was the story behind that one?” Recently, I came across such a gem in the form of a patch titled “Implement close-on-fork”. The actual patch is fairly pedestrian. It frees up some resources when forking a new process to prevent a possible race condition within the “system” C library function. What’s interesting is that the team at Garmin have found some behaviour in their application code they didn’t like (“system” in Linux isn’t implemented the same way as it is on Solaris, and is documented to not be thread-safe). Instead of addressing it with a relatively trivial change to the application, they embarked on an odyssey…

The major desktops all have their own file managers. Gnome has Files (formerly Nautilus), Mint has Nemo, MATE has Caja. These are all excellent at doing bread-and-butter file management, and all have their own unique features, including file labelling, batch renaming, metadata editing, and searches that integrate with the desktop’s indexing. We could compare those, or include them, but then to one degree or another the comparison boils down to desktop philosophy. No one’s going to choose a desktop based solely on its file manager, and no one’s going to install, for example, Files on KDE (because despite dragging in a bunch of Gnome libraries it won’t work quite the same). So here we’ll round up file managers that aren’t beholden (beyond perhaps requiring one of GTK or Qt) to…

In its natural habitat (a fully fledged Plasma desktop), Dolphin will integrate with Kfind. It can also work the popular Catfish, FSearch and ANGRYsearch tools. It also has its own built-in search tool, which in a Plasma desktop will use the native indexing to search inside files as well as filenames. You don’t need to know any advanced syntax to use it and there are dropdowns to search by file type, date or rating. Krusader has a built-in search that can narrow results by size, date or owner. Regular expressions can be used to search inside files, and results can be put into a virtual file system that you can return to later. To get back there after you close the tab (or program) requires you to manually navigate to…

YOU NEED Raspberry Pi 4 or 3B+ Raspberry Pi Camera Raspbian A breadboard 2x Female to male wires 1x Push button (Momentary switch) Code: https:// github.com/lesp/LXF 264-Stop-Motion/archive/ master.zip Wallace and Gromit, Morph, the evil skeletons created by Ray Harryhausen… these are all famous examples of an animation technique called stop-motion, which uses individual images posed by an animator so that when run as a sequence, the subject appears to move. Traditionally this takes many hours or days of painstaking work. But using the power of the Raspberry Pi and its camera, we can make our own movie studio. In this tutorial we shall make a short animation using a LEGO model, all filmed using Python and the Raspberry Pi. The button that triggers our camera is a push button inserted…

You might be reading this thinking, “Google Stadia – isn’t that the naff one with no games?” and you’d be partially correct. While it’s true that Google Stadia doesn’t yet boast a games library to challenge Xbox One or PS4, it’s far from naff. A few features (such as sharing screenshots and videos) took a while to mature, but Google Stadia is a game streaming platform worth some consideration. With a relatively modest internet connection you can enjoy perfect streaming at standard resolution. It really is as if the game is streaming on a console on your home, rather than on a remote server somewhere. Ethernet delivers the best results to the streaming device (whether a Chromecast Ultra, Android device, desktop PC or Raspberry Pi), so all you need to…

Ever wanted to become a self-published author? Looking for a simple way to create a digital publication – whether book or magazine – that can be read on a variety of devices? The solution lies in creating your book in EPUB format, which formats your book using familiar web languages (XHTML and CSS). The resulting content is dynamic and responsive, meaning it can be viewed on screens both large and small without needing adjustment. The process of putting an EPUB document together from scratch might be daunting, were it not for the likes of Sigil (https://sigil-ebook.com), a powerful but user-friendly eBook editing tool. Even then, its array of features and options might be a little intimidating, which is why we’ve done all the hard work for you, uncovering the key…

The latest version of Sigil introduces a file-versioning feature called Checkpoints. Each checkpoint is a snapshot of your eBook at a specific point in time, enabling you to compare changes between versions and even roll back to an earlier version. You’ll see the Checkpoints toolbar appear beneath the Styles toolbar next to the Index Editor. It comprises four buttons: create new checkpoint, create a new ePub file from the previous checkpoint, compare current ePub against previous checkpoint, and a tool for managing checkpoint repositories. Make sure you’ve saved your ePub at least once before creating your first checkpoint. Versions are stored locally in a local git repository created and maintained by Python, which can be found in the ‘repo’ folder in your Sigil preferences folder. When comparing versions, select your…

You may have considered creating a project using either the Arduino controller range of boards or any of its compatible systems. If you have, but were put off by having to buy new hardware just to try it out, then why not simulate your idea before splashing out the cash? All the software you need is on Linux and you can see what the different boards are capable of beforehand. In this tutorial we’re going to learn what you can do with virtual boards and the right software. You can create all the components and connect them to your board, program the controller and see how it handles it. You have several CLI options including simavr, simulavr and a few others, too. There are many different packages available for designing…

Circuito enables you to build your circuits and test them, all in one application. There are many components available at www.circuito.io. When you add components, the system suggests the wiring and creates the initial code for you to download. Of course, you’ll also be presented with a long shopping list. Pick what you’d like to have or search elsewhere for the parts. You can download all the files and continue your project locally. This tool explains how to place the wires, determines the amount of power you need and suggests a new power supply when required. Somehow, it also creates a guide about how to wire it up and get it running! With this tool, you can speed up your projects by leaps and bounds. If you start with the…

Elasticsearch (www.elastic.co), Kibana and Logstash enable you to collect data, store it and visualise it. Logstash is the tool for managing events and logs – Logstash usually sends its data to a storage engine such as Elasticsearch because Elasticsearch can’t work on its own. This means Elasticsearch requires software for collecting data and other software for analysing and visualising data. Kibana offers an analytics and search dashboard for Elasticsearch as well as visualisation capabilities for data stored in Elasticsearch. Kibana is so handy that it would be a shame to use Elasticsearch without Kibana. You won’t need to work so much with Elasticsearch directly because you’ll end up using Kibana to collect and process data stored in Elasticsearch. Note that Logstash can process your data before storing it to Elasticsearch,…

Speed up Pac-Man by increasing or decreasing the ‘onkey’ values, at the bottom of our code (x,y). Remember that positive numbers move right or up, and negatives move left or down. Have a play around with the colours in the World() function to create some funky-looking versions of Pac-Man. Credit to Grant Jenks of Free Python Games for the code reference. We wouldn’t have been able to create a vector graphics based Pac-Man game, or indeed describe ‘flooring’ without his instruction.…

This month’s coding tutorial is on D3.js, a powerful low-level JavaScript library that can create unique, highly customisable and impressive graphical output based on your data. For reasons of simplicity most of the examples shown here will include the data that will be visualised in the HTML file that contains the JavaScript code. However, D3.js enables you to read data from text files that reside either on your local machine or online. The D3.js (Data Driven Documents) library can be downloaded using a <script></script> tag in the HTML page that contains the JavaScript code. The code processes and creates your visualisations, so there’s no need to download it locally. Additionally, you’re free to read the JavaScript code of D3.js and make any changes or improvements you want to it! There…