That’s Life…on a Hackaday Badge

Our Hackaday Chief [Mike] sent me an e-mail the other day with a link to the Belgrade Hackaday Badge simulator. He clearly wanted me to enter something into the demo scene competition. The good news is that because of the simulator, you didn’t have to leave your desk to participate. The bad news is that I had very little time left at the end of the month, so I wanted to do something appealing but it had to be fairly easy to roll out. I wound up doing a very quick project but it had a few fine points that I thought I’d share. The end goal was to have an interesting display of Conway’s game of life on the badge.

By the way, there was a completely different project with the same goal by [Jeremias] on Hackaday.io. As far as I know, this was just the result of two people setting out to do the same thing. You’ll see the user interface is a good bit different, so you might see which you prefer.

If you haven’t seen it, the real badge is below. The emulator, of course, just runs as a window on your PC. For those that will be at the conference, or just want to program closer to the actual hardware, there is now a preconfigured MPLABX framework  for the PIC18LF25K50 and the bootloader/kernel running on this badge.

Continue reading “That’s Life…on a Hackaday Badge”

Insanely-Quick 3D Tracking with 1 Camera

Let’s face it: 3-dimensional odometry can be a computationally expensive problem often requiring expensive 3D cameras and optimized algorithms that can be difficult to wrap our head around. Nevertheless, researchers continue to push the bounds of visual odometry forward each year. This past year was no exception, as [Christian], [Matia], and [Davide] have tipped the scale in terms of speed with an algorithm that can track itself in 3D in real time.

In the video (after the break), the landmarks are sparse, the motion to track is relentlessly jagged, but SVO, or Semi-Fast Visual Odometry [PDF warning], keeps tracking its precision with remarkable consistency, making use of “high frequency texture” as a reference. Several other implementations require two cameras or a depth camera variant, but not SVO. It uses a single camera with a high frame rate between 55 and 300 frames per second. Best of all, the trio at the University of Zürich have made their codebase open source and available as a package for ROS.

Continue reading “Insanely-Quick 3D Tracking with 1 Camera”

Code Craft: Cross Compiling for the Raspberry Pi

Sometimes there’s just no place like your desktop. You’ve already got your favorite development tools and references setup or installed and it’s a pain when you’re trying to work on an unfamiliar, or simply uncustomized, system. On your desktop everything is at your fingertips. If you want to search the web, the browser is just an alt-tab away. If you need a calculator, it’s right there to run. Your editor highlights syntax in your favorite colors already.

When developing on a Raspberry Pi, you leave all these creature comforts behind unless you spend the time to configure the Pi to your liking. Then it all gets wiped when you install a new distribution, like the recent change from Wheezy to Jessie. Even then it’s frustrating to switch back and forth between the desktop and the Pi because there is always something on the other system that you need. My usual comment is, “dirty word”, literally.

Cross-developing on your desktop is a very workable solution. We’re going to walk through setting up your desktop and a Pi to do this. This means loading a Pi ARM toolchain on your desktop and a debugging server on the Pi. This’ll let you develop and debug from in the comfort of your desktop. An added advantage is when you put that Pi in a robot you can debug over a wireless link.

Continue reading “Code Craft: Cross Compiling for the Raspberry Pi”

Crosswords Help You Learn Regular Expressions

Regular expressions might seem arcane, but if you do any kind of software, they are a powerful hacker tool. Obviously, if you are writing software or using tools like grep, awk, sed, Perl, or just about any programming language, regular expressions can simplify many tasks. Even if you don’t need them directly, regular expression searches can help you analyze source code, search through net lists, or even analyze data captured from sensors.

If you’ve been using regular expressions for a long time, they aren’t very hard. But learning them for the first time can be tedious. Unless you try your hand at regular expression crosswords. The clues are regular expressions and the rows and columns all have to match the corresponding regular expressions.

Continue reading “Crosswords Help You Learn Regular Expressions”

Test Drive Your New Programming Font

After hour and hours spent in front of a terminal or IDE, a user begins to build a list of infuriating little things. That one pop-up box that happens every time you press that button by mistake. The noise the software makes when the compile fails. Or the horrible reality that your code just crashed because there wasn’t enough difference between uppercase ‘O’ and a zero. In comes the programming font.

The typical way to find a programming font is to troll forums for a user with a similar problem and see if they have a workable solution. [Koen Lageveen] went out and found nearly all of the free programming fonts out there and compiled a list. He then took one more step and wrote a web app that lets you test them out. Hopefully this will help those in the very real struggle for the perfect programming font. You can try out the tool for yourself, and if you really like it [Koen] has all the code up for it on his GitHub.

[via Hacker News]

Wolfenstein in 600 Lines of Code

What’s more impressive, the fact that this Wolfenstein-like game is 600 lines of code, or that it’s written in AWK?

AWK is a language primarily used for text processing. But if you can write code the world bows to your wishes. [Fedor Kalugin] leverages the ability of a Linux terminal’s color options to draw his game. The 3D aspect is produced through ray-casting which generates a 2D image from 3D coordinates.

Trying out the game is extremely simple, install gawk, clone the repo, and play:

Continue reading “Wolfenstein in 600 Lines of Code”

Code Craft-Embedding C++: Hacking the Arduino Software Environment

The Arduino software environment, including the IDE, libraries, and general approach, are geared toward education. It’s meant as a way to introduce embedded development to newbies. This is a great concept but it falls short when more serious development or more advanced education is required. I keep wrestling with how to address this. One way is by using Eclipse with the Arduino Plug-in. That provides a professional development environment, at least.

The code base for the Arduino is another frustration. Bluntly, the use of setup() and loop() with main() being hidden really bugs me. The mixture of C and C++ in libraries and examples is another irritation. There is enough C++ being used that it makes sense it should be the standard. Plus a good portion of the library code could be a lot better. At this point fixing this would be a monumental task requiring many dedicated developers to do the rewrite. But there are a some things that can be done so let’s see a couple possibilities and how they would be used.

Continue reading “Code Craft-Embedding C++: Hacking the Arduino Software Environment”