Coding A Gameboy Game – In An Hour?!

UnSeen Gamescreen Just another Saturday night and I noticed the one hour game jam was on in a minute or two. So, time to roll up those coding sleeves and bosh out a game based on the theme “Stealth”

One hour really isn’t much time to make a game in so I had to use some fairly ugly hacks to get the game working, it’s a simple affair, guide the shadowy character to the “WIN!” text and you win. that’s it. Whilst security beams are switched on and off, with animation, audio cues and walking sound effects. The only collision routine used is that with the background layer. There’s so little time to get anything working that my collision routine is a little iffy, resulting in sliding along walls.

onehouroneNevertheless, I’m glad I managed to make something “slightly” more substantial than my previous one hour game jam attempt under the theme “Everything is dangerous” again, simple enough, avoid the spikes, walls, etc. Just under an hour.

Even though these games aren’t much, it’s nice to try an intense burst of game coding every now ‘n’ then!

Download Links for the ROMs below:

Formula Racing Gameboy Homebrew Developments.

Well, it’s been around a month since I’ve posted on here about the updates to Formula Racing and there’s a lot more going on with the game now! Read on to find out about what’s done and what’s still to go.

What’s done?

More tracks! 

There’s now 10 tracks designed for Formula racing, including my new personal favourite USSR – 1! I’m going to be re-visiting the track designs for previous levels shortly, in order to spruce them up a tad.

More Track Details!

I foolishly forgot that I had a spare 128 tiles to use for either sprites of background tiles.. So, I’ve been making use of the new tiles to add more definition to the track layouts. Mainly USSR-1!

Track obstacles.

Just racing the opponents wasn’t enough for me after a while. So I’ve added more obstacle tiles that will blow your car off track should you run onto them. You will run onto them!

Boost Tiles.

Because, every racing game needs boost tiles of course! So far, only on USSR-1 but that’s fine. Revisiting older tracks, yeah!

Track Intros, last lap warnings, Variable Lap counts Per Track , an actual finish AAAND that vital feature. Pausing.

So, yeah, that’s a fair amount of stuff added to the game which has had a couple of important effects.

The games plays better and is getting closer to being an actual game now.

I’m seriously running out of spare ROM space for my main game loop – 270 bytes at last count tonight. I have sfx to add and music!


Yes, that’s right, MUSIC! I’ve been chatting to the fantastic gameboy chiptune composer NordLoef about in-game tracks and he’s agreed to help make some music, which is really great news, I can’t music for toffee, cake, biscuits, even the promise of coffee and a peanut butter wrap.

So, yeah, he’s going to be in the game credits and, hopefully getting a physical cartridge at some point! I’m really looking forward to importing the tracks into the game, that’ll really make it a more complete gameboy game and hopefully some people out there will enjoy it also?

ION – A gameboy action puzzle game in GBDK in development

Despite not having many hour last weekend for Ludum Dare, I started to put together the pieces for another lil Gameboy Game called ION. Where you take the role of a charged particle that needs to attain certain levels of charge to proceed to further levels and boost the players score.

It’s a fairly simple game in essence and uses ice physics for motion control with state-based A.I. charges that vary between seeking and fleeing routines to keep the player on their toes.

Here’s a quick 20 second video with some of the game in action.

There’s still a way to go, but I’m planning on adding obstacles, slow and charge wells to help mix the gameplay up.

Gameboy GBDK Tutorial ROM Code!

Yes, it’s finally here, with comments and everything! Below is the code for the C file and I’ve included all the files with a readme.txt file for your perusal here. I hope this helps you to get started on your gameboy development journeys!

gbdkdemo .zip file, 6kb



A sudden Jolt, of Gameboy Goodness!

So, I noticed that Gamejolt now allow you to play gameboy ROMs directly from your browser, that’s pretty cool I thought, best upload some games I’ve made to see how it runs then.

And, lo and behold, 5 games uploaded and they all seem to be emulated rather well, they even included CGB (Gameboy Colour) Support on there also.

5games-ongamejolt-nowIt seems like a nice place to host the files, they’re not going to take up much space either way, but gamejolt serves as a handy place to put them all! View, Play & Download these lil Gameboy beasties here!

Why the long delay?

Because I’ve been busy beavering away in GBDK of course! Here’s a brief video with some nice details on progress with the game and, what needs to be done before I put it out in the wild.

It’s taken a long time but I’m over the 50% mark now, just need to cram the code into what space I have left (just over 2k in my main rom bank)

I think I’ve finally found a solution to my super gameboy problems, which I’ll be playing about with this week, it’s exciting stuff for me at least!


The doubts of homebrew development

I really love Gameboy development. It’s been the only game platform I’ve made things for since November 2015. But there’s that niggling part in me that reminds me occasionally that I could be working on finishing a more commercial game off when I’m coding up something very niche indeed.

There were different niggles going on with me when regarding indie development though. Mainly focusing around hopes that this game would appeal to people enough to purchase it or play a free version which could generate some revenue in another way. Kinda like a really long approach to purchasing a lottery ticket, particularly with the mobile market nowadays it would appear.

That’s not to say I’m not going to make another game with intentions of selling it though, but despite the differing niggles with Gameboy homebrew. I think I prefer them to the ones which seem more saturated than ever before.

Maybe that’s partly due to the different challenges involved between languages / IDEs. Unity is great fun to play around with and you can easily do a lot with it quickly. You’re a lot more limited with the Gameboy in every which way but those limitations, much like the time limitations in game jams, tend to make me produce something I wouldn’t otherwise.

I dunno. I kinda like it here in Gameboy Development land, just not to the exclusion of modern game dev. At least, not yet.

A couple more screens done and more bug fixes.

A bit more code tidied up tonight. Along with plans to get some more screens set-up for save/ continue functionality.

18 Courses should be enough, each course area will have it’s own theme and colour scheme for colour gameboy players. We’ll see how it goes from here but I’m hoping to fit this into 64kb total. Well, maybe 128kb, depending on any extras I add to it.

Grand Prix and Select CoursePasswords will just store your current course and total points. Maybe with different endings for different points totals at the end of the season…I dunno.

Could Undertale be made to run on a Nintendo Gameboy?

demake-largeSo I’ve just finished one of the most hectic weeks at work porting 10-13 year old code over to PHP7 and I decided to chill out with some Undertale pacifist mode playing about when my goddamned coders brain thinks to it’s self…

“Damn, I love Undertale and having a good time… but. I reckon this game could run on a Gameboy, which would be pretty cool, yeah, yeah?”

That’s not to slight the game, I love it, I doubt I’ll have the heart to do a genocide playthrough mind. But, looking at it objectively, could it be possible to port over to it? I mean, undoubtedly compromises would need to be made in terms of sprite sizes, and music downsampling but from the outset, you have a load / save system, background scrolling and fight sequences with conversation pop up boxes. Of course, there’s the over arching story with it’s many branches which would no-doubt push memory to it’s limits I’m sure and, whilst I doubt I’d attempt to port the game myself to GB, I think it could be done.

That and I had to see if the Undertale GUI would fit in the Gameboy’s tiny resolution, looks like it could. Apologies for my poor scaling of Napstablook btw 🙂

Right, back to finishing off Formula Racing ‘n’ stuff…

More Formula Racing Features Added!

Okay, it’s been a while but, yes life, is a thing and it isn’t always coding of course 🙂

Having said that over the weekend just gone I’ve managed to get more of the game ready, including part of the opening sequence which just needs some palette work for the gameboy colour so that’s all in motion.

I’ve set-up the ability to have multiple levels in the game and I reckon I can easily fit a decent number in there, possibly with each one having it’s own variants in both colours and some other elements to break things up a bit.

I’m tempted to learn how to add a border for the super gameboy also, although I’d need to learn some more ASM first in order to figure this out.

Sadly, it looks like I won’t be finished for the February #1gam but, that’s okay, I’ve got more of a workable engine to use across the year for any future gameboy games and that’s pretty neat.

Speaking of engines… Damage is now a factor with your race car. Taking damage impacts acceleration and once the limit is reached, you will explode, lose three places, then respawn. Crashing into the back of another car or off track obstacles is particularly painful!

Cars get tougher to pass the further up the rankings you go and I’m still enjoying playing and making the game so, that’s all good for the moment I think! Now, back to figuring this Super Gameboy out a bit perhaps….

[edit] I shouldn’t have made this border, now it’s a mission! [/edit]