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Virtual Reality: A Review

A considerable number of different 3D glasses scattered around. (Above: A considerable number of stereo 3D glasses technologies. Can you name all the techniques shown here? Comment below!)

Yesterday I spent a morning experimenting with my University's latest stereo equipment as part of the Virtual Environments module I've been taking this semester. With all that I've seen, I wanted to write something about my experiences on here.

Virtual reality and 3D is something that I haven't really had the chance to experience very often. In fact, the last time I was truly able to experience 3D was also through my University - probably through the open day (I can't remember). I've also never had the experience of using a controller before - which I'll talk about later.

With this in mind, it was all a rather new experience for me. The first tech we looked at was a stereo projector with active nvidia shutter glasses. They work by using a variant on the LCD to block out each eye when the image for the other eye is being shown. To this end, they need to sync this with the PC - hence their active nature - and the reason cinemas usually use clever cylindrical polarising filters instead (especially since the screen must be running at a minimum of 120Hz to avoid sickness and provide a reasonable experience).

Even so, the experience was quite amazing - even after seeing it once or twice before. With the additional knowledge about the way stereoscopic images are put together (using techniques such as parallax and concepts such as depth cues and depth budget), I found that I could appreciate what was going on much more than I could previously.

The head tracking that was paired with the shutter glasses was absolutely fascinating. If you were sitting in the seats in front of the stage you got a bunch of window violations and a pair of hurting eyes, when you were on the stage with the tracked glasses, it was a whole different story. It was literally like a window into another world - made all the more real by the projection onto the floor!

We also took a look at the cave, as it's colloquially known - a variant on the screen with 4 panels of a cube, with pairs of projectors back-projecting onto each of the sides - with the same infrared-based head tracking technology. This, too, was similarly cool - it has the ability to make you feel unsteady when looking down from the crows' nest of a large navel ship....

Though this is probably old news to most readers of this post, I found that the idea of using an Xbox controller to move the user around was quite a clever solution to the awkward issue that you can't walk around yourself much unless you like walking into invisible boxes wireframed in black. It certainly felt more natural than using a keyboard - which would have felt bulky and out-of-place. I'll be paying more attention to both controllers and other forms of alternative input when designing applications in future - as I've seen first-hand what a difference the appropriate form of input can make to the overall experience.

Until today, I've also been rather skeptical of Microsoft's HoloLens. Sorting through all the microsoft-speak and buzzwords is somewhat challenging - but the lectures we've had over the last 5 weeks helped with that :D The headset itself is actually plenty comfortable (especially compared to the Oculus Rift), and the head-tracking is astonishing - especially considering that it's all inside-out (as opposed to outside-in). The holograms really look like they're hovering in the environment around you - apart from the fact that they're clearly computer generated of course, and the gestures are actually pretty intuitive for how different the experience is to anything else I've experienced before.

The biggest problem though, as you're probably aware, is the small field-of-view. It's offset slightly by the fact that you can see around the hologram-enabled area, but it still causes frequent window-violations and only covers a fraction of your effective vision - which they don't appear to take any notice of in their marketing material (see the image below - the pair of people in the image can probably only see the very centre quarter of that thundercloud). If they can fix that - then I think that they may have something truly world-changing. It could be used for all sorts of applications - especially in engineering I think.

An image of a pair of people standing altogether far too close to a holographic thundercloud diagram.

The sound system built into it was cool too - I didn't manage to check, but I'm pretty sure only I could hear it, but it sure didn't sound like it! In the tutorial it really sounded like there was a voice coming from all around me - which leads me to think it might be programmable such that it appears to come from anywhere in the room - so you might even be able to have a conversation with a holographic projection of someone standing on the table in front of you (like Microsoft's holoportation demo).

Finally, we took a look at some of the things that the department have been doing with the Oculus Rift. VR is an experience on a whole 'nother level - and best experienced for one's self (it's really important to remember to clean the lenses in the headset thoroughly, and spend some time aligning them precisely to your eyes I found - otherwise everything will be blurry). I found the latter half of the (rather extensive) setup tutorial I went through later that day to test my ACW particularly immersive - to the point where you had consciously remember where you were in the real world - personally I had my leg just touching the edge of my chair to remind me! Though the audio wasn't as good as the HoloLens (see above), it was still adequate for the task at hand.

While I was running through the first-use setup tutorial it was evident though that it was quite clearly a Facebook product - in that you had to create an account (or sign in with Facebook), set privacy settings, and a few other things it hinted at during the setup (I was interested in testing my code I'd written, so I didn't explore the consumer side of the device), so if you're concerned about privacy, then the Oculus Rift is certainly not for you. Thankfully there are lots of other virtual reality headsets around to investigate instead :-)

The controllers made for an interesting experience too - they were a clever solution to the awkward problem that they couldn't track your hand as well as they'd need to in order to display it fully in virtual reality (Microsoft had it easy with the gestures for their HoloLens, apparently) - and they didn't end up breaking immersion too badly in the tutorial by roughly simulating your hand position based on which buttons and triggers you had pressed down. Definitely much better than a keyboard in this instance, since you couldn't even feel where the keyboard was in virtual reality - let alone find the keys on the keyboard to press, and that's not even mentioning the loss of movement and rotation you'd experience.

In conclusion, my whole view on stereo 3D, VR, and input methods have all been changed in a single day - which I think is pretty good going! Stereo 3D and Virtual reality is never going to go away - the potential behind it just far too tempting to not play around with. Designing applications for VR is going to be a challenge for many developers I think - since an understanding of depth dues and immersion is essential to designing effective experiences that don't make you feel sick. We can't leave the real world behind with VR yet (walking into a chair or table is an unpleasant experience), but what we've got right now is absolutely astonishing.

The other side of the fence: A Manjaro review

Oen of the default Manjaro wallpapers. (Above: One of the default Manjaro wallpapers.)

Sorry for the delay! I've had rather a lot to do recently - including set up the machine I'm using to write this blog post.

For a while now, I've been running Ubuntu on my main laptop. After making the switch from Windows 7, I haven't looked back. Recently though, a friend of mine suggested I check out Manjaro - another distribution of Linux based on Arch Linux . After setting it up on a secondary machine and playing around with it, I rather like it, actually - and I've decided to write a post about my experiences coming from Ubuntu.

Like most things, I've got multiple different reasons for playing around with Manjaro. Not least of which is to experience a different ecosystem and a different way of doing things - namely the Arch Linux ecosystem. To that end, I've selected the OpenRC init system - since I've got experience with Systemd already, I feel it's essential to gain experience with other technologies.

With my preferences selected, I fired up manjaro-architect (available on the Manjaro website, which is linked above) and began the installation. I quickly found that the installation was not a simple process - requiring several reboots to get the options just right. In particular, the partitioning tools available are somewhat limited - such that I had to boot into a live Ubuntu environment to sort them out to get a dual boot setup working correctly.

On the other side, the installer allows the configuration of so many more options, like the mount options of the partitions, the kernel to use and it's associated modules, the init system that is used, and the desktop environment you want to use (I've picked XFCE). During the install process I've learnt about a bunch of different things that I had no idea about before.

After installation, I then started on the long task of configuring it to my liking. I'm still working on that, but I'm constantly amazed at the level of flexibility it offers. Nearly everything can be customised - including all the title bar graphics and the ordering and position of everything on the task bar (called a panel in XFCE.

I've found OpenRC an interesting learning experience too. It's very similar to upstart - another init system I used before Ubuntu switched to systemd. As a result, it's so uch simpler to get my head around. It feels a lot more.... transparent than systemd, which is a good thing I think. I do miss a few of the features that systemd offers, however. In time, though, I'm sure that I'll find alternative ways of doing things - different projects do have different ways of thinking, after all!

The concept of the [AUR]() (The Arch User Repository) is possibly one of my faviourite things out of all the things I've encountered so far. It's a community-driven archive of packages, but instead of containing the package binaries themselves, each package contains instructions to fetch build, and install said package.

This way requires much less maintenance I suspect, and makes it much easier to stay up to date with things. The install process for a package from the AUR is a little complex, sure, but so much easier and more automated than doing it by hand. It's like taking the benefits of downloading an installer manually from a program's website like you have to on Windows, and combining it with the ease of use and automation that comes with package managers like apt (Debian-based distrubutions) and pacman / yaourt (Arch Linux-based distributions).

In short, Manjaro is a breath of fresh air, and very different to what I've tried before. While it's certainly not for the linux beginner (try Ubuntu or Linux Mint if you're a beginner!) - especially the installer - I think it fulfills a different purpose for me at least - as platform from which to explore the Arch Linux ecosystem in relative comfort and dive deeper into the way that all the different parts in a linux system interact with each other.

Achievement Get: Upgrade Server - A writeup of my experiences

An open and a closed box.

The upgrade is complete! I've managed to move practically everything over to the new server, apart from a few automated cleanup tasks here and there. There are still a few issues floating around, but they shouldn't affect this website, and I should have them cleared up soon. Although the migration went smoother than I expected, I did encounter some issues and learnt a few things that I thought I'd share here.

The first thing I found was that starting a todo list isn't a rather good idea. It sounds simple, but it's actually really useful. I found that I had a lot of small tasks I needed to complete, and I kept thinking of more things that needed doing at regular intervals. If I didn't write them down I'd never get anything done because I'd never be able to remember what needed doing first!

It also helps to do your research before you move. Make sure that you're properly reaquainted with all the software running on the system that you're going to migrate from, and that you're familiar with all the ins and outs of your particular situation. If you aren't, then you risk stumbling across some rather nasty, complicated, and time consuming problems mid-migration.

It also helps to do as much of the migration as possible without taking the old system offline. Install the software, Move the configuration files. Set up the firewall. Set up your new monitoring tools. This allows you to minimise the downtime that you have to subject your users to, which is always a good thing.

Lastly, testing is incredibly important. test everything. Make sure that every little feature after you migrate. You'd be surprised at how many issues can crop up after migration.

C++ in Review

I started learning C++ back in September, and I think I've experienced enough of it in order to write a proper review post on it. I've been wanting to do this for a while, as I have quite a bit to say about it.

I think I should start off by saying that C++ is complicated. Very complicated. To the point that you could learn about it for years and still not be half way through everything that you could learn about it. While this offers unparalelled customisablility, it also makes it difficult for new programmmers to pick up the language. Even worse is that whilst something might work, it could easily contain a critical security bug that can be extremely difficult to spot.

It's also difficult (for me anyway) to remember what everything is and what it does. For example, a const int* is not the same as an int* const. I find myself constantly looking things up that I forget over and over again. On top of this, a large number of the core built in functions don't actually do what you'd think they would. For example, getline() doesn't get a line of text, and fail() checks to see if an error occurred whilst opening it. These names can't be corrected in a later version of C++ either - later C++ versions must be able to compile previous versions of the language, including pure C from 30 years ago. Perhaps this is what makes it so difficult to use?

The other thing that makes C++ annoying and difficult to use is how low level it is. You end up having to do almost everything yourself - even things that you'd think would be built into the language already. The standard template library (STL) provides a large number of methods and data strutures to fill in the gaps, but most of these are misnamed too (the vector class is actually similar to a C♯ List), so you end up implementing your own anyway because you can't find the class you want in the STL (only to have someone point it out later).

Thankfully, there is a reason why everyone is still using an old broken language to write important code - it's practically the fastest language out there short of assembly language. No other language comes close to rivalling C++ in speed. Is this the only reason we are keeping it?

My favourite Atom packages

The atom banner.

A while ago I posted about how much I like the Atom editor. A few months on, and I'm still in agreement: The Atom editor is an absolutely lovely general purpose editor. It's got a bewildering array of plugins, and I thought that I'd share a few of my favourites with you.

Termrk has to be my number one. It adds a toggleable terminal to the bottom of the screen (and presumably other sides too!). This is particularly useful for sorting out particularly nasty version control system problems, or using a quick one liner to process a few files, or starting a development server in the background. If you know your way around the console / terminal, this package is a must have.

Git Plus is also really useful. As you might suspect, it brings git integration to atom. It has a gui for all the common git commands - committing, branching, pushing, pulling, and more. If you use git, install this package.

Minimap and friends are awesome. If you didn't know about the map mode for the scroll bar in Visual Studio (go to tools and search for "map"), this package brings that to Atom. It has a bunch of plugins, too - which let you preview other points on the minimap, or show the current selection, or show changes since the last git commit. Its appearance is simple and uncomplicated, with one 'pixel' for each character - coloured according to that character's colour. I've been finding it to be just what I need when you're dealing with a large complex codebase. (and minimap-titles is an awesome extra too)

If you use multiple computers, sync-settings is worth a look. It synchronises your settings and installed packages by using a Github gist. I use it as a backup for my settings, but it'll be also useful when I finally get around to setting up a portable installation of atom on my flash drive.

There are a ton of other brilliant packages out there that I've found and I could write about them all night, but that would make this post way too long :) If you're interested in which packages I've got installed, I've uploaded a list to pastebin.

Happy New Year 2016!

Welcome to 2016!

I wanted to write this post to wish you a very happy new year! I also wanted to thank you for being a part of the first full calendar year for which this website has been live. Out of curiosity, I counted the number of posts I've made on here this year, and the total came to 104, which works out to roughly 1 post every 3½ days.

Just a few of the highlights of 2015 include Rob Miles' Coding Conundrums series, continued website improvements and better spam defences, and the EcmaScript 6: Features and Learning Prolog series.

In this new year I'll be continuing my learning Prolog series, and probably posting a bit about networking and 3D stuff, since I'll be taking a module in each of these areas.

My thoughts on Basecamp

Basecamp's Logo

For the last few months I have been using basecamp to coordinate and communicate with my group for a (rather large) piece of coursework. I've had a reasonable amount of time to get used to basecamp and how it works, so (upon request) I thought that I would share thoughts on it here.

To start with, the summary page gives a quick overview of what has been going on recently, without giving you that feeling of information overload. The discussions are good too - they are arranged in chronological order with the avatar of the most recent commenter next to each post. The files section is ok, but it feels rather cluttered and would be more helpful if you could upload a new version of someone else's file.

The problems start in the "To-do lists" section. You can create multiple lists of items, but you can't create subtasks or tasks that depend on other tasks. This makes basecamp rather unsuitable for software development as I often find that in order to fix one issue I have to fix another first. I also like to categorise my todos (which basecamp doesn't support either) - GitHub issues do this very well. The ability to assign multiple people to a task would also make working in a group much easier. I also found that once I'd created a few todo items, it quickly got to the point where I couldn't tell them apart - it just looked like a big wall of text, but that is probably just me.

The last thing I haven't mentioned yet is the events tab. Here you can create events and have basecamp automatically email (optionally selected) people, which is nice, but a special field to specify the location of the event would be welcomed as I found in my group that the venue of our meetings kept changing. A number of different views on the calendar would make it even better - the month view displays too much time, and I always get times mixed in the agenda view.

To conclude, Basecamp is a good project management tool that you can use when working in a group, but is still a bit rough around the edges. I wouldn't use it for software development, but I'm not ruling it out for other kinds of projects (although I think that trello would probably better float my boat, depending on the situation).

Thoughts on GitHub's new theme

GitHub's new look.

The other day, I got a notification on GitHub asking me to try their new website redesign. Now that I've had time to think about it, I thought that I'd make a post on what I think about it.

To start with, the design as a whole feels more modern and a little bit more 'flat'. I'm not sure if this is a good thing or not yet, though it does make the interface feel less cluttered. This makes the content that the interface is presenting easier to digest.

The only exception to this is the top of the repository page, especially the code view (the view that you see by default). Having the different sections of the repository along the top rather than down the side makes it feel like there is more going on than there was before - and it can feel a little bit overwhelming at times. Add to this the new "Add file" and "Find file" buttons, and it really starts to feel rather crowded.

Having said that, cutting the design down to use a single column makes the interface a bit more consistent with the mobile view. This is a good thing - although I found that reducing the width of the page caused a horizontal scrollbar to appear - perhaps it would be better to allow the new design to resize to fit smaller screens? It also opens up more space that can be used to display other things - like the list of a repository's issues, or the network graph in the "Graphs" section (there's a bug with the network graph by the way - it appears to be cut off just before the edge of the box).

Having a single wide column also makes a repository's README (and other markdown documents) easier to, um, read. It makes them feel more like a webpage and less like a file that someone's uploaded, though this wasn't a huge issue for me before.

All in all, GitHub's new interface is an improvement. It's an improvement overall, which makes the interface feel more modern. The top of the repository view feels rather cluttered and definitely needs rethinking.

My thoughts on SVN (or how to use git-svn to avoid it)

My university uses SVN as their preferred source code control system, and I came into contact with it for the first time the other day. For one of the modules I'm taking this year all the lab work is located in a special SVN repository. The ACW (assessed coursework) also has to be submitted through this SVN repository.

I found that (after some simple mistakes) it's not particularly difficult to pull down a repository - just a little bit fiddly (you have to create the directory to clone a repository into first). The trouble started when I tried to commit my changes. I found it almost impossible to just do a simple commit that contains all of the changes I'd made so far, though I might be missing something.

SVN itself feels rather clunky and outdated in the way it works. It doesn't have an inbuilt fork system, and you can't commit if you are offline (or if the central master repository is offline). Git, by comparison, supports both of these things. In addition, git apparently has better support for branching and merging, though I haven't come into contact with it yet.

My solution for this for now it to use git-svn. To check if you have it installed, simply run the command git svn --help. If it's installed, you will get a help message. If not, you'll get a harmless error message. On Linux you can install it via sudo apt-get install git-svn. On Windows you should have it installed by default.

With git-svn, you can clone an SVN repository much like you would for a regular git repository: git svn clone https://path/to/svn/repo. This clones a remote SVN repository down into a local git repository.

From here you can do any number of git commits as normal. When you are ready to push your changes back up to the remote SVN repository, simply run git svn dcommit. This will push all of your git commits up to the remote SVN repository as revisions.

Hopefully this post is helpful to someone. If I'm missing something here (and I probably am) please leave a comment below!

Update: If you need to pull down remote changes from the server, simply run `git svn rebase.

Ubuntu: Second Impressions

Ubuntu's Default Background I've had my laptop dual booted with Ubuntu for a while now, and I've been using Ubuntu in a Virtual Machine and as a live CD, but I've only just gotten around to rearrenging my partitions and reimaging my Ubuntu partition with Ubuntu 15.04. Previously, I had a bunch of issues with ubuntu (for example my laptop kept heating up), but I seem to have solved most of them and I thought that I'd post here about the problems I encountered, how I fixed them, and what I think of the latest version of ubuntu.

Firstly, I installed ubuntu from a live CD iso on my flash drive. Annoyingly, I used the 32 bit version by accident, and had to do it again. It would be nice if it told you which version you were about to install. Anyway, I found the installer to be rather temperamental. It kept freezing for ages, and all I could do was wait.

After the installation finished, I was left with a brand new, and very buggy, 64 bit Ubuntu 15.04 installation. As soon as it booted, the first job was to stop my cursor from flickering. Because I have an Nvidia GeForce 550M GPU, Ubuntu didn't recognise it properly (it detected it as a second 'unknown display') and so custom drivers were needed to fix it. I found this post, which guided me through the installation of both bumblebee (to control which of my two GPUs I use), and the official Nvidia drivers for my graphics card.

After banishing the flickering cursor, I found my laptop cooler, though it still wasn't right. Next up was to install thermald, indicator-cpufreq and lm-sensors. This trio of packages automatically controls the frequency of your CPU to both save power and prevent overheating. Normally, linux doesn't pay any attention to the frequency of the CPU of it's host system, leaving to run at it's maximum speed all the time - which causes battery drain and overheating.

Now that my laptop wasn't overheating too much, I could focus on other problems. When in Windows 7, I have something called SRS Premium Sound. It is brilliant at tweaking audio just before it reaches the speakers to improve it's quality. I quickly found when I got this laptop that it was essential - the speakers are facing downwards and the output sounds 'tinny' or 'hollow' without it. Since linux doesn't have SRS, the next best thing was PulseAudio, which provides you with an equaliser to tune your sound output with. Note that PulseAudio does actually work with Ubuntu 14, even though some people have said that it has been discontinued (I don't think it has?).

The other thing that needed changing was my touchpad. I felt like I had to hammer it in order to get it to recognise my touch, whereas in Windows it picked up the lightest of touches. My solution was to add the following to my .profile:

synclient FingerLow=2
synclient FingerHigh=3
synclient AccelFactor=0.145
synclient TouchpadOff=0
synclient MinSpeed=1.25
synclient MaxSpeed=2
synclient CoastingFriction=30

This improved the responsiveness of my touchpad a whole lot to the point where I could actually use it without getting frustrated :)

That covers the main problems I came across. As for what I think, I'm finding Ubuntu to be a great operating system to work with - now that I've worked most of the bugs out. Things like indicator-cpufreq and thermald ought to be automatically installed on systems that support them at install time. You should also be prompted to install bumblebee and the offical nvidia graphics drivers at install time too, as a system with multiple GPUs (i.e. integrated graphics and a graphics card) are pretty unusable without them. Sensible default settings would be nice too - nobody likes hammering their touchpad just to get a response.

The Ubuntu unity desktop developers seem to have remvoved a bunch of configuration options from the GUI in recent releases. Hopefully they wil readd them - it's rather annoying to have to enter the terminal to change something as simple as the login screen background.

On the plus side, Ubuntu seems to load much faster than Windows 7, and is more responsive too. I also feel like I have more screen space to work with as there isn't a task bar taking up space at the bottom of the screen. The customisability is amazing too. I am finding that there are far more things that you can tweak and fiddle with in Ubuntu compared to Windows.

To finish off this post, here's a list of smaller problems I had, and a link to the appropriate post that fixed it for me:

Art by Mythdael