A little while ago I saw a really cool project that got me really excited
about microprocessors and tinkering with hardware. I've been aware of the Arduino project
for a while but my limited grasp of resistors and capacitors was holding me back a little.
A couple of weeks ago I caved and bought myself a Genuino Uno and a basic starter kit from
Amazon. Once I'd built a few of the tutorial circuits I started looking around for other projects to
build; the Gamebuino project above is still a little beyond my skills but definitely something I want
to work towards. Whilst looking around at the various things people do with their Arduinos I came across
an awesome Quadruped robot and wondered how I might build one of my own. I kept browsing and
found BoB the Biped. The cool thing about BoB is that he only needs 4 servos and I happened to
already have 4 servos that I'd preserved from an RC plane I had as a really young kid! I (literally)
dusted them off and hooked them up, one at a time, to my Uno with the Sweep tutorial
loaded and was amazed when each of my 20-year-old servos worked flawlessly!
The instructables BoB is made from 3D printed parts, but I don't have easy access to one of those, plus
I wanted the option of maybe using it as a project with my students in the future so I decided to try
building him from cardboard.
I stole a few unused packing boxes from a recent office move at work and set to work cutting and gluing
the parts - shape was taken from the pictures with rough measurements that felt right at the time.
I worked on the legs first - I was a bit foolish to start with, cutting long pieces of cardboard,
gluing together and then bending them to try to make the 'L' piece. These didn't come close to
bearing the weight of a single servo, let alone all the other stuff. I initially flirted with
the idea of adding struts to add some extra support until I realised I was looking at it from the
wrong angle. I cut 4 'L' shaped pieces of cardboard and glued them all together to create a pretty
sturdy leg. I used PVA glue to stick the layers together, which seems to actually add a bit of strength.
Next I measured out my servos and cut a 'Pelvis' with holes to drop them into. In an effort
to save some weight (and drawing time!) I only cut 3 layers. I was pretty proud when the 3 sections
were glued together and the servo cutouts matched within less than a millimetre!
I used a hot glue gun to glue the servos into the holes and the legs onto the servos.
Next I used the headers and some old protoboard I had laying around and soldered up a simple connector
board that provided 6v of power using 4 NiMH AA cells. I used the same cells to power my Uno via the Vin
connector and although 6v is a bit low for the voltage regulator according to the docs, it seems to
I made a cool head to cover it all by cutting carboard panels and hot-gluing them together. It's a little
rougher than I'd like but I'm going to add proximity sensors and other features later on, so I'll likely
build a new one to mount those into. I think this one was a little too tall as well, which caused a few
Coding was next. I've been using a mixture of the official Arduino IDE and a web-based editor called
codebender. I do intend to put my project code into GitHub, and I think codebender can
interface with that but I need to investigate.
In the meantime, codebender lets you share code with a simple link, which is a little bit neater than
pasting it all up in here:
So I had the idea that if I created a pixel art palette, any art that I make in the future will be inter-compatible - so when I make bunch of robots for a dystopian future thriller game, they'll fit right in lurking in a cave re-purposed by a bunch of orcs.
Or something like that anyway - it's a nice way to fill an afternoon and I think I have something I like.
16 is the traditional number of colours so I went with that. There are still a couple of colours I'm not completely sure about, but I'll only really know for sure once I start making things with it.
Back in October I mentioned that I was looking at learning WebGL. I finally managed to find some time to do it this month
and have made some pleasing progress.
My plan was to start off creating a simple 2D framework to replace jaws.js. I've been using this framework since I started
playing around making games and I really like its simplicity, but I was butting up against its performance. Since it had a load of
stuff in it I'm probably never going to use, rolling my own seemed like a good idea.
My first attempt was very disappointing from the performance point of view.
I asked for help. I was doing so very little with my demo that I couldn't understand why the performance was so poor.
I got some pointers and was able to make some changes. Basically, you can't do lots of buffer\push\draw operations very fast in WebGL.
You have to break them down so that you're buffering a whole load of points into memory then drawing them all at once. I was able to get
much better performance by creating a SpriteBucket. drawing ~500 sprites at a time appeared to give me the best balance,
giving me >10,000 sprites @ 60fps.
On the whole, I was unprepared for how delicate the balance was between getting reasonable drawing rate and not. I naively thought that
WebGL was a super powerhouse of graphics processing and I would only start to have problems when I started trying to do stupid things. I
suppose you could argue that plastering 5000+ sprites on the screen at once and redrawing everything constantly is stupid, but my
LD30 game had tilemaps and monsters that could have potentially approached this and it didn't run very well.
With a few obvious tweaks like not bothering to draw stuff off screen (duh!) and only updating vertices and texture coordinates if something
has actually changed I saw immediate improvements. The less obvious (to me at the time) stuff, like buffering batches of sprites for a
single draw call made the biggest difference.
The end product from my dalliances this month was Glixl. Glixl can create sprite and tile maps from 2D sprite sheets. It goes
pretty fast if you pay attention to what's being drawn, although there are still areas I can improve. My intention is to use this for
my games from now on, so I'll be developing it as I go, adding features that I need. Some things that I still need to work on:
Mouse & Touch controls
Tilemap path finding
and I need to improve the SpriteBucket object as it has a few things I feel are hacky. Overall though, it does exactly what I want it to do.
I've started making a simple game, Dojo Master. to test it too, which is working out quite nicely. So far I only had to add 1 feature to get it working.
Sadly I wasn't able to participate in Ludum Dare 31.
I thought the theme was interesting. I know there were some complaints that it
was overly specific and made 3D games harder or impossible. It was actually one
of the themes that I voted for though because I thought it would be fun.
When I woke up and found out that was the winner, I immediately had the idea of
doing a classic platformer with multiple levels all visible on the screen at once.
I notice today as people start submitting that there are a few other people who had
the same idea and they do look awesome!
I got as far on Saturday as making a little 8-pix character, Henry:
My plan was to set up as many 64x64 levels as I could all joined together, with
puzzles or bosses to defeat to unlock the door to the next space.
Alas, I was unable to do it. I might play around with the idea, but with so little time
to do much of anything these days, Henry's dreams of rescuing his dragon will likely remain
forever unrealised. Poor Henry.
I spent last week in the New Forest with my family. Apparently this year is a very good year for mushrooms. As we were walking around the forest, I saw lots of different types and some of them made some nice photos. I did have a go at identifying them but it's quite tricky and the only one I am reasonably sure about is the second to last one which looks like a Vermillion Waxcap.
I made a discovery this weekend. It has taken me almost a year to make the realisation but it
was striking when I noticed:
I've never been a particularly prolific blogger, but 2014 is easily one of my worst years yet.
It's no co-incidence either that the last post of 2013 was about me moving my blog to GitHub.
In moving it to GitHub I created a barrier to making posts.
Previously, I've always built my own blogging engines and they have always come with web-based
front-ends for managing and posting articles. I could quickly navigate to my blog, log into the
control panel and post an article.
The workflow for posting an article from GitHub is really not that difficult but it adds a few
small extra steps that act as barriers to me actually bothering to do it and it's a real shame.
I have a solution. It's still in progress but the primary functionality is already in
place - Burble is a microblog hosted on GitHub as a GitHub Pages site that includes
repository, completely bypassing the need to fire up an editor, sync or clone the repository,
generating the file with the right name, writing it, committing it back etc etc.
I have some bigger plans for Burble itself, but once I have got the editor working fully (currently
it only allows the posting of new 'blurbs', no editing or deleting), I will be able to use it to
manage my main gh-pages hosted site (this one!). I'm quite excited about both projects, which will
hopefully inspire me to write about them a little more.
This weekend I took part in Ludum Dare, the build-a-game-in-48-hours competition.
The theme this time was Connected Worlds. I had an idea fairly early on - Scientist (Rodney) accidently opens a portal to another world, gets stuck and has to try to find his way home. Definitely not original, but it was a start.
I was particularly pleased to be able to use some of the pathfinding features in Jaws that I contributed a while back too!
Overall I was pleased with my finished product. It wasn't quite as ambitious as I had planned for but I finished it and it makes some kind of sense.
Things I was pleased with
Enemy AI - It's laughable to call it AI really, the Bat Fiends look around, if they see Rodney they move to intercept. But it really worked. It looks really cool when you walk into a new void area and a whole flock of Bat Fiends come chasing out of some side corridor after you. It's the little things.
Art - I am no artist, but I've been developing my pixel art skills over the last year or so and I was actually pretty pleased with the result:
The bat fiends were pretty simple, but cool looking:
Things not so pleased with
Sound - Howler turned out to be brilliant, really easy to use and just worked. My ability to create sound effects however needs much development. Music I completely failed with, no idea where to start. Definitely an area to work on for next time.
Animation - I definitely need to work on my walk cycles!
Fun - I'm not completely convinced that the game is actually much fun. It was quite cool when 3 or 4 portals in, I found myself tunneling through the walls to get around instead of walking through open areas because there were so many bat fiends, but I'm not sure it had much lasting appeal.
I had a lot of fun working on this. Technically, I'm quite pleased with it, but conceptually, it could be better - I think I need to spend the next few months playing as many computer games as possible to get a better idea of what makes them fun.