I’ve received word of when my talk at Notacon 8 will be: Friday, April 15 @ 4:00PM-5:00PM in the Edison I conference room.
Schedule is subject to change, I’m sure, but if it does change I’ll post an update.
These are the cards I'll be handing out at the event
First, who would have thought that one small component of AI behavior for my game would have taken so long to get working?
I was on a good roll, making steady progress on my project for most of December. Then the holidays hit and I couldn’t work on the project as much as I wanted. I had also just started to run into some stuff that was a little tricky (not that it was really hard, just that it was new to me) around this time, so the lack of putting time into it also made me feel nervous that I’d get stuck. There’s no way I’m ever giving up this project until I complete it, and that’s that, but I’ve run into problems in the past with projects where I get stuck, don’t know where to turn, and it sucks a lot. Oftentimes that puts the entire project at risk. But this is a project that I’ll never accept failure on — I’m working on an idea I had 30 years ago, and if it’s been in my head that long, and not gone away, it never will.
So, into January, I had less time than I hoped to get back into the project. When I did, I wanted to make the time productive, so I tended to pick things that I knew I could do, and that needed doing, but not necessarily the thing I’d gotten stuck on. That’s OK, but normally when you see something is going to be hard for you to figure out, you should wade into it and tackle the problem. I didn’t do this with myself, so much as I tried an idea a little bit, and when it didn’t do what I was expecting, I put it aside again and worked on something where I had more traction. I had a fatalistic sense of “When I am ready for this to make sense to me, it will.”
Also, during a lot of this time I was spending a lot of my project time on reading documentation, not coding. It was a struggle to make sense of what I was reading. My mind kept tripping up on something that didn’t make sense to me, and which in the end turned out to be inaccurate (unless I *still* misunderstand something, but I don’t think so). So that wasn’t too helpful.
In the reading that I did, I discovered a lot of things that merited further reading, and had to trace down a lot of avenues that potentially could have led to my solution, but didn’t. This wasn’t wasted time, though, because a lot of that stuff may end up becoming useful later, and having a clue that it’s out there is going to be helpful down the road.
Ultimately, I was able to prevail over my problem, get un-stuck, and deliver a working proof of concept. I need to do some further work to turn this proof of concept into an extension that I can import into any future Game Maker project that I work on, and from there I still need to bring it into my game project. But that’s all academic, and I have no doubt that I will get it done, and so I’m able to confidently declare victory at this point.
My initial attempts to implement the solution I was after focused on doing it directly in the current game project. I’ll call that a mistake now. For one, the existing game already has a lot of stuff in it, and the complexity of it makes it difficult to see (or think about) any new problems clearly. I had several false starts which ended up failing, trying this way.
Eventually, I got to the point where I recognized that what I needed to be able to solve the problem was simplicity. So to get that, I started a new project, and threw into it just enough bare bones to provide me with the building blocks I needed to test out the AI code that I was trying to figure out how to write.
So I did that. Twice. The first time was almost right, the second time was right, at least so far as it went, and I’d figured out enough to know that what I’d built there would work for what I need, but I need to do the rest of it back in the main project. The first attempt help me to figure out what I was doing wrong, or rather, what I needed to do.
So, that exercise was very beneficial. The second attempt only took me about 5-6 hours of hacking away at it to get it to work, which is about par for every other feature that I’ve committed in the project so far. So the fact that it took a few weeks of thinking, procrastinating, reading, and trying various things doesn’t worry me so much. I know the next time I get stuck with a problem like this, I’ll get to the solution that much sooner because I can take this general approach to it.
What was the most useful for me in solving this was the stuff I built into the project to provide me with feedback so I had something to diagnose. I strongly recommend building instrumentation and logging capabilities into whatever code you write. Otherwise, you’re only able to see what you can observe from the outside, which often ain’t much, and is apt to be very confusing when the application is behaving in some bizarre, unexpected way that you can’t figure out based on what you thought your instructions were saying to the compiler or interpreter.
After several weeks of effort, I have finally nailed an effective set of 2D targeting scripts for AI in Game Maker 8.
The story for this is worth telling sometime, but for now I’ll just be posting a video demo:
Source .gmk is available on Releases.
I’ll be refactoring this into a Game Maker Extension (.gex) soon as well, which will also be available along with full source.
When writing scripts in Game Maker Language projects, I have come to realize a couple things that I want to share for anyone else who might be working on GML projects:
GML parsing is a bit loose. This makes the language fault tolerant, which is nice for newbie programmers who don’t need to get beaten up for not following strict syntax. But by enabling you to get away with imprecise syntax, it lets you get in to trouble that isn’t easy to detect.
Strict syntax is your friend, if you have it as an option in the language you’re using, I recommend following it as soon as you’re comfortable. Strive to get comfortable as quickly as possible. Unfortunately, GML does not have a strict mode…so I have the following tips to offer:
create() event), and you are declaring the variable in the script, but you want to make it an instance-local variable, you can do so. The code to do this is:
obj_MyObject.MyLocalInstanceVar
That dot between obj_MyObject and MyLocalInstanceVar is actually an operator. Knowing this is nifty, but I am not prepared to expound on why just yet.
Keep reading the language specification doc! Every time I go back to it and read, I pick up something I didn’t know, or refine something I thought I knew. One of the really nice things about GML is that it’s a small enough language that you can pick it up and do things with the basic features right away, without needing or being overwhelmed by all the other stuff that you’ll discover as you continue to progress as a developer. And there are enough built-in features in GML that you don’t have to spend a lot of time figuring out how to build sophisticated stuff out of primitives all by yourself.
The more I work in GML, the more respect and appreciation I gain for it. It is not the purest language, nor is it the most powerful, nor is the development environment as rich and sophisticated as a “serious” IDE like Visual Studio or Eclipse, but it is extremely accessible for a non-programmer to pick up and start working with and being effective quickly.
Good technical documentation is a beautiful, beautiful thing. Almost as good as bug-free code.
It occurred to me recently that my Actions could be easier to understand and debug if I refactored to convert as much of it from Drag-and-Drop actions into GML scripts. It’s a LOT easier to understand a script call to “Player_Eats_Fish” than it is to read a dozen or more DnD actions that do “Player Eats Fish” and figure out what they’re doing. Plus, you can call the scripts elsewhere if you need to.
So I started doing this, and realized that there were certain things that I didn’t know how to do. Reading the language reference in the GameMaker Help helped, but at times I still got confused… Then I googled and found this. UDnD2GML does a nice job of converting Drag and Drop actions into valid and correct GML. It’s actually written in GameMaker, too; that’s right, it’s a GameMaker project that converts GameMaker drag-n-drop actions into GML. Very slick! When you need to work out a bit of tricky syntax, or are dealing with some function you don’t use a whole lot, it’s indespensible.
Basically the same thing, only a big hypertext reference document. I liked it so much, I printed it to PDF format and am keeping it with my other GameMaker docs. Although this is for GML7, there doesn’t seem to be a whole lot that has changed in GML8. Could be a bit clearer in places, and incomplete in some regards (I had to use UDND2GML to figure out how to apply instance_destroy() to other; this document was silent on that point.)
Not hard to find by any means, but if you don’t have it, it’s the best place to start. A lot nicer than searching through the Help Menu index.
I’ve spent the last few days getting back into the Boobie Teeth project, trying to figure out how to do a couple things that have had me stuck for longer than I’d care to admit. I’m far from giving up, but I have come to the conclusion that hacking away at the problem isn’t going to be as fruitful as reading up on the problem.
At any rate, here’s a video of what I managed to pack in to today’s release, 0.17:
The major accomplishment for this release was the addition of a transparent gradient in the foreground, which enhances the background gradient that gives the illusion of diminishing sunlight at depth. For now this is just a cosmetic feature, although I already have ideas for tying it into the gameplay.
The other thing I worked with in this release, but dropped for now, is to implement some basic AI. I want the fish to get hungry and start chasing down prey. This is a lot harder than I thought it would be, owing to limitations of GameMaker’s instance handling. My usual approach of coding a little bit and seeing what I get, then coding a bit more once I’m sure what I already have done is working hasn’t gotten me very far. I’ll be researching and studying until I figure out an approach that works.
While researching, I came across a beautiful video of some lighting effects done in GameMaker which blow my simple foreground gradient away completely:
I noticed of course that the video appeared to come from French-speaking authors, but that didn’t dissuade me from tracking down the package that enables these effects and downloading it.
Let me just take a moment to say that I am absolutely amazed by the quality of google’s translation service from French to English. Seriously, click this link and you’d hardly even know that you’re on a French site. This impresses me even more than the lighting effects. If you happen to spot a mistake in translation you can hover over text and see the original, and provide feedback to google directly through the site that they’re translating for you. The translation is extremely fast, almost real-time, too.
It’s going to take me some time to work my way through the examples and tutorials and translating the documentation, but if I can get this SmartLight to work with my game project, it’s going to be well worth it, and make the game look way better than I had originally planned. I really want to get some AI going in my game though, so it’ll probably be a while before I get into re-doing the lighting effects.
So in Boobie Teeth 0.15, I created a surface for my ocean. The way I designed it, if you breach the surface of the water, gravity takes hold of you and you fall back into the ocean. Beneath the surface, no gravity.
I didn’t realize it until I played for a while, but if you breach the surface and wiggle the controls, the input seems to give you extra momentum, which can keep you above the water indefinitely. This wasn’t what I desired, but I wondered whether I should do anything about it. Should I consider it a glitch? Should I leave it in, and let the player discover it? Gamers like to discover things like this, and it’s kindof fun, if useless, to fly about over the waves. But if I leave it in, I should give it some purpose.
I have to think about it for 0.16. Maybe something will come to me. Maybe if you fly about enough, you can get someplace secret.
I don’t like when I design something and it doesn’t work the way I conceived it in the beginning, but sometimes I like the surprise. Even when I do like the surprise, I like to figure out what went wrong and figure out how to make it work the way I originally intended. Maybe I’ll keep it in mind for later.
So I figured out a way to fix the problem, it was easy enough: just set the controls to be disabled when you’re above the water. This causes your above-surface trajectory to become purely ballistic, but at the expense of not being able to control your direction at all. Conceivably this could cause you to leap out of the water, only to be doomed by your trajectory to land right on a big fish that will eat you when you plunge back into the water.
That seems so much less fun than being able to fly out of the water for as long as you care to wiggle the stick. On the other hand, I don’t want there to be a cheap, easy way of avoiding danger indefinitely.
There may be another way. I might just need to find a way of making the simulated gravity increase each step of the game engine until it can’t be resisted. Then you could still wiggle, and might be able to gain a little bit of extra effort air while out of the water, and affect where you will splash down somewhat, likely enough to evade big fish near the surface. I’ll have to play with it and see. Sometimes this experimentation ends up being fruitless, other times I can figure out something useful and understand the tool or the model better than I did. Usually the experimentation is time consuming. But generally, it’s worthwhile.
Any time I run into a design crossroads like this, I think the solution is easy: it’s like Yogi Berra said: “When you hit a fork in the road, take it.” Keep all interesting variants, and make them configurable options. Play through the different options and keep them for as long as they make for interesting play. Some options may make it into the final game as official options, some may be used as hidden easter eggs, others may end up disabled. But keeping the options around as long as possible makes for a more agile course through the development process.
I just captured a video of Boobie Teeth 0.15, the latest build. It’s up on YouTube.
Ok, I realize that GameMaker isn’t a hard core developer environment. It does serve a purpose though: to provide a more accessible means for aspiring game designers who are not primarily programmers to be able to give life to their ideas. This is a truly noble purpose, in my view and I will never say anything bad about GameMaker’s technical limitations as long as they’re limitations which must exist in order to achieve that goal.
That said, I am really starting to get frustrated with the GameMaker community. Not its members, mind you — the handful of interactions that I’ve had with GamMaker devs have been helpful and positive. But what is really driving me nuts in the community forums is the way people will post links to filehosting sites, and the link is dead because it’s a few months later. This is totally counterproductive to the goal of making a game dev environment that’s welcoming and forgiving to newbie programmers and non-techie types.
The forum thread is there, the tantalizing discussion about how awesome a solution is to just the exact problem I needed to solve is there, but the .gmk or .gex file that would make my day is gone. And not enough discussion around the gaping hole to figure out what the solution was that was demonstrated in the downloadable file.
But it’s not just an everyday occurrence. It’s damn near mandatory. And super frustrating.
.gmk files *usually* take up very little space, and if you don’t need all the resources embedded to create a full-fledged game, you can make *extremely* lean .gmk files that can provide a reference implementation of your nifty solution…. AND, we live in an age where 2TB hard drives cost under $100.
So, WTF? The GameMaker community would be so much better serving its users if it provided permanent hosting space so that discussion threads could remain relevant.
I really don’t understand it, I mean if you go to yoyogames they have graphic and sound resource packs that you can download. They’re of poor quality, and searching for anything in them is atrocious, but they at least have links that still point to extant resources. They even host all the games that people submit to the site.
Clearly they have the technology, why are they not using it in this way?
I was over at my parents house for Christmas. When I was a kid, my mom kept a bunch of my old school assignments and things up in the attic. I had hoped that I’d be able to go up there and find some of the old game ideas that I had drawn when I was in first and second grade, but unfortunately it seems within the last ten years she went and got rid of a lot of that stuff, and turned the rest of it into some scrapbooks. Unfortunately, it appears that most of my old ideas were lost, other than to my memory.
There was just one thing that I did find among all of that stuff, which might have been a video game concept. The strange thing is, this one I have no memory of making. The drawing is of BunnyBots, which looks a bit like Lemmings, only with bunny robots. That field war machines and artillery pieces, apparently. They fire carrot missiles at each other and drop easter egg bombs and have tunneling equipment for digging rabbit holes. Gameplay evidently resembled a 2-player PvP 2D horizontal scrolling RTS.
Mind you, this was probably drawn in 1982-3, long before Lemmings or real-time strategy existed.
I dunno when or if I’ll ever turn this concept into a game, but here’s a scan I made of the drawing:
Original drawing for BunnyBots videogame concept. Click Image to enlarge.