Open source devices for the disabled

In one of my mobile games I had used music from Eric Skiff, and I heard he is starting a new company which makes open source devices for the disabled. So I thought I would give a link for everyone to check out if you are interested.

Here is the video which talks about their aims. Pretty cool stuff!

They have a Kickstarter campaign as well in case you are interested in helping out.


Japanese podcast about games: “Game chomp chomp”(ゲームモゴモゴ)

Recently I discovered an awesome podcast that discusses a variety of games, and one of the hosts actually works the business of developing them.

While you’ll need to know at least some Japanese to appreciate this, if you do it’s a great way to study up on Japanese as well as the art of game making.

You can more details about this podcast in my post here (on my blog about Japanese study).

Update: Failed prototype and competing hobbies

I haven’t posed to this blog in a while so I thought I would give a quick update.

The prototype I was working on for several weeks (traffic-related mobile game) didn’t turn out to be as fun as I’d expected. I still have this idea in my head about how cool and interesting it would be, but having trouble translating that into actual gameplay. If the game isn’t fun to me, then it likely won’t be fun to anyone else, so I’ve shelved that project for now. At some point I should probably think about what elements were good about it and what weren’t, and make a write up about it.

The other reason I had taken a break from the prototype-work was that I had went on a trip to Japan, and since I came back I’d spent much time writing up all my experiences and thoughts about that trip. You can see them here in case you are interested.

I actually have a new project that is bouncing around in my head, similar to a previous one in that it involves a card game. But I’ll save that for another post.

Mobile Game Review: Lost Echo [iPhone/iPad]

I discovered this game from the promotional category “15 Greatest Storylines” in the iTunes store for iPad/iPhone. Most of the mobile games I download are free, but an impressive trailer plus the fact that the game was on sale ($0.99 from a usual price of $2.99) was enough to make me buy this game. Lost Echo has been out for some time, released on Sep 2013 for the first version.

This game is an authentic adventure game where you control the main character, following a storyline that gets pretty mysterious after the first few minutes of play. The game’s graphics are all 3D rendered in real time, and depending on where you move the camera angle changes, sometimes gradually and sometimes suddenly.

When I first saw this game’s trailer on my iPhone, I was blown away by the graphics, but after playing it for about an hour or so on my iPad my impression dropped a notch. This is not only because the larger screen size shows off the flaws more easily, but because the design quality of the environments varies significantly, with some contain areas of very simple geometry that stand out. Also, the app preview shows some of the more interesting and better-designed areas, which is only natural from a marketing point of view. Overall they have done a great job with texturing the environment to create realism without using too many complex models.

I’ve been playing for around 90 minutes total time, and the story and dialogue is pretty well-written so far. I am not sure if they are purposeful, but I feel there are similarities to some of the Final Fantasy Games (story and dialoge-wise), plus Half Life series (mostly visual). I haven’t played many true adventure games on iPhone/iPad, but it’s great to know there are some serious adventure games like this on mobile devices. The only drawback story-wise is that sometimes I feel this game devolves to a click fest where I have to just click on everything in sight until I hit upon the right object.

The controls on the game take some getting used to be able to efficiently navigate the world, but even given this learning curve I think there are some things that could be improved. For example, clicking on a location to move there does not normally show any UI confirmation, unless you have happened to click on a hotspot representing a object or other important place. This makes for a frustrating experience, especially because sometimes it isn’t clear whether the place you clicked on is a legal location to walk to. Usually I end up clicking many times quickly to make sure the character starts moving.

There was one scene I just played involving a card game where clicking on a button on an overlaid menu to look at my hand of cards didn’t work properly – instead it acted as if I was trying to touch something on the backdrop, giving me the message “This is a wine crate”. Eventually I figured out I had to click my cards on the table first but I was almost ready to give up. There is one more short scene involving fixing a rattle that was surprisingly hard to control, and I feel that part should be cut completely from the game since it didn’t add anything tangible to the experience.

I also had to struggle with the camera angle, since it would change unpredictably and sometimes I didn’t know where I had to send my character to force the necessary angle change. I think some of this is unavoidable in adventure games with dynamic camera angles, but I think they could refine things a bit. Once you get to the camera setup on each area it’s not that bad though.

For some reason, part of the time when I was playing this game there was no music, even though I had my volume turned up all the way. When I went back and played the next day music was suddenly working, and from what I’ve heard it’s pretty good. This issue might be related to my device, however. Another thing that I experienced once is my iPad getting extremely hot after playing for a few minutes, though this too could be a device-specific problem (it’s an older model).

Almost immediately after starting this game I could tell it was a low-budget effort – not in a negative sense but rather that the team tried to do the best with limited resources. For example, the fact that areas are reused several times in the story, and also the fact there is a lot of dialogue. Both of these things could be attributed to their storytelling style, but with a big budget I’m pretty sure would exposed more areas to be explored.

Looking at the developer’s site (KickBack studios), the team is in fact very small with only two people, who must have worked very hard on this game (their first) in the last two years or so. I’d be very happy if I could ever make a game this cool that could get such visibility from Apple, and I’m looking forward to this studio’s future releases.

Despite the few flaws and annoyances, for $0.99 this game is totally worth it, so I recommend you check it out on iPad or iPhone.


Game development: reducing scope (traffic simulation)

One of the tricks of game development, especially that done by small teams, is reducing scope of each feature or element to a minimum necessary level. It is critical to make efficient use of developers’ time since there is only so many cycles available, and the longer a project goes on the more likely it is to get cancelled or postponed. The more games you get under your belt the more you start to care more about this kind of stuff.

To give an example of this – one of the core elements of my latest game in development is a series of connected roads with cars running through them, a little like what you would see in a modern version of a SimCity-type game. Starting several weeks ago, I experimented with several different ways to implement this “traffic simulation” element in my game.

Initially, I started with the idea that I would use Unity 3D, since that would allow me to show a very realistic simulation of cars moving through a network of roads. I was inspired by the mobile game Does Not Commute, which uses a 3D engine to good effect.

However, after learning a little more about the Unity 3D workflow, I realized I would be spending a big chunk of my time on the graphics and other 3D elements, which would make the core gameplay elements (behavior, logic, rules) take that much longer to do. Though the end result might look quite attractive, I had doubts that I could finish the game on my own if I took this route.

So for the time being I decided to make the game 2D. My next decision was whether I should use a physics engine or not. I’ve been interested in physics engines myself for some time, having made very simple ones years ago, so I decided to download and experiment with a few different frameworks, including Box 2D. In only a few hours, I was able to get some test programs running and there was a surprisingly rich set of functionality for the free frameworks I tested.

But again, I posed the question to myself – do I really need detailed physics simulation? Is having cars collide, spin out of control, and follow a physically accurate path really critical to my game’s core gameplay? While this would be a cool feature, I eventually decided this was overkill, and again reduced the scope of my traffic simulation efforts.

At this point I entered into prototype development, spending my evening hours making a bear-bones traffic simulation where each car was resented with only a handful of properties such as color, location, and speed. I got this working and am now experimenting with different game objectives, and creating stages to see what is actually fun (and challenging) – the most important aspect of any game.

If things go well and I feel I’ve made an entertaining prototype, I can continue to polish the visuals, or even consider going back to 3D. With a proven game idea, the risk for failure would be greatly reduced.

If I had determined that simulating cars as individual entities was not a critical element of my game, I could reduce scope yet again and simulate at a coarser granularity. For example, in the original SimCity game (which happened to be the first game I purchased with my own money), traffic was handled by road-piece granularity, where a stock animation was selected based on the traffic density of that area at the given time. You couldn’t follow a single car around since they would appear and disappear if you looked closely. While a system of roads was important in building an efficient city, tracking an individual car from point A to B wasn’t necessary, and players had more to concern themselves with. Also, I believe the original SimCity was only made by two or three developers. In more recent versions of that series it seems that cars are modeled as individual entities.

I’ll post some more about this project as things progress.

Dokusen: The Art of Domination (iOS puzzle game) — A month later

It’s been a month since I released my latest iOS game Dokusen on iTunes. At first I considered polishing some aspects of the game and releasing an update, but to be honest the idea of developing a new game from scratch is more attractive, so I’ve stared down that path instead. So in a sense you can consider this post a “post mortem” of this game.

At heart, this game was an experiment to see if a bigger focus on visuals would reflect in more popularity in the store. I also spent a much larger chunk of time advertising on net forums, on roughly 20-30 different sites.

From a downloads perspective, my personal goal was to get at least twice the downloads of my previous game. Initially things went great, with the number of downloads from Dokusen in the first two days surpassing those from the first week of my previous game. Unfortunately downloads suddenly decreased after that on the 3rd and 4th days, such that I only reached 75% of my target downloads (to date, Dokusen got 1.5x of my previous game’s count). Though this is a bit of a disappointment, I should look on the bright side because at least things are going in the right direction. The large spike on the first two days is still a bit of mystery to me, since with previous projects downloads leveled off at a much slower rate. Oddly, I got a large majority of downloads those first two days from France.

These numbers are a further confirmation that advertising on net forums is not a great way to pull in downloads. I did, however, get some good feedback on the game’s rules from on a board game forum I posted on, since it shares some elements with Go and Reversi.

A week or two ago I talked to one of the people who informally tested for me, and he remarked that my previous game was much more fun and easier to understand. This was good feedback, though altogether not that surprising since I feel the same way. Ironically, with Dokusen I had tried to build a game that would be popular with others, but not necessarily myself.

For my next game (codename “T.E.” for the time being), I am planning on making something which I enjoy more myself, in terms of both coding and gameplay. I also plan to make a proper tutorial, as well as get more playtesters (please leave a comment if you are interested in helping). This next game is rooted in a longtime passion of mine, and the work I’ve done on it already is more challenging and interesting than Dokusen. I’m aiming for a release in 3-6 months if things go well.

Though I implied this project was mostly done, I am always open to feedback on Dokusen or any of my other apps. If you looking for someone to review your game I am OK with exchanging reviews of your game for mine.

Programming Trick: Speeding up your recursive loops with a creative technique

Lately, I’ve been working on a new game project which is very different than all the other ones I’ve done so far. I’m planning on waiting until it gets a little further before I write about it in detail on this blog, but I ran into an interesting technical challenge and I’d like to discuss how I solved it.

To implement the game mechanics I need a graph of nodes, with various connections between each node. I have a need to find the shortest path between two nodes, where the path is calculated by the sum of the length of all connections as part of the path.

I started out with a simple recursive algorithm that started from each node and worked backwards to find all possible paths to get to it, and used a map to store the best connection to move, given a certain intermediate node and a certain destination node. This worked really well, although after around 13-14 iterations on a graph with many connections it started taking over a second to compute and them getting exponentially worse.

One option was for me to search for a more proper algorithm to find the shortest path, and I am sure this has been perfected by  programmers over the last few decades. But I had a secondary requirement to also store all non-optional paths as well, so some of those algorithms probably wouldn’t suffice.

Looking at my recursive function, I realized that there really wasn’t much going on in terms of sub-functions it called that do any significant calculation. If there was, I could try to optimize those or cache up some result. But the question remained – what was taking up all the time?

Looking at the function again I saw that I was passing four different arguments into it. If you have ever studied assembly, you probably know that there are several instructions just to push and pull each of these to and from the stack, and since the function is called so frequently I thought that maybe this added up to a big chunk of the total time.

I decided to test my hunch by making all the parameters into global variables. I purposefully didn’t use class variables since I knew there would be extra lookups required, translating to extra work for the CPU.

It was a bit of work to make this transformation, since for non-pointer variables I had to manually save the state before calling the recursive function, and then re-set it. But this was only for two of the variables since the other two were pointers anyway which were supposed to change (one was the map which stored the nodes that had already been traversed so far, and I already had code to adjust that when returning from the recursive function).

The resultant code was a bit harder to follow, but the performance was significantly better. For the test case I was using I was able to get several more iterations before it got significantly slow (>1 second), if I remember correctly to at least 19-20 iterations.

If I keep adding nodes and connections eventually it still gets slow again, but I will probably put limits on these anyway so I may be safe with this solution for the time being.

Although I enjoy designing games from a high level, after many years of coding I still enjoy these types of algorithmic challenges, and the satisfaction of a well-tuned function.