Let's talk about the metronome again, shall we? I believe a metronome system is a component worthy of being included in all game engines. They have a lot more to offer game developers than simply playing sounds to the beat of the music. What I really want to get across is how the metronome event system can help unify the timing of many elements in games, making them feel complimentary.
It Started Small
Our first title with a metronome events system received a nomination for best sound in Kotaku’s 2008 Game of the Year. We owe this, in no small part, to the music source provided by the one and only Mr. Les Claypool. However, it was the metronome that made this game stand out.
Mushroom Men’s metronome is locked to 120 BPM. You could say this is a simplistic or limiting approach, but I believe it was an inspiring limitation. We came up with this grungy dub-funk music style and it set the mood for every level in the game. After hearing enough 120 BPM music during production, it became pretty natural to design sounds to the same tempo. Eventually, we even had particle effects artists designing their particle animations to the beat, such as light bulbs blinking and buzzing to a certain rhythm. One level had a small airship that carried you from one platform to another, and our metronome made sure it didn’t move until the next metronome beat happened. We wanted to play a rhythmic, delayed-out musical stinger whenever the airship moved.
Learning to be Subtle
I think there’s real potential to take this a step further with metronome-linked events that don’t call attention to themselves. I worked on a different project last year that also had a metronome, but this one was designed and built during pre-production and received lots of updates throughout the course of working on the game. I spent some time prototyping a level that aimed to show off what the metronome could do.
While working with drawbridges, doors and rotating platforms, I found the metronome was an awesome tool that replaced the typical arbitrary time value ‘guessing game’. The level designer’s original version of the level had seconds-based timers determining when the platforms would rotate. I changed them to rotate based on a counter that incremented every 4 beats. There was a draw bridge that the player could unlock with a key. Once unlocked, the drawbridge would swing down to open. Originally this was set up to happen over a second or two but I changed it so the locking mechanism waited a beat before finishing, causing the drawbridge opening event to always start on beat, then had the opening sequence span two beats.
This sort of thing isn’t immediately apparent as being ‘on the beat’, but lots of nice, seemingly coincidental (emergent?) timings can happen. Sometimes the music will have a nice fill for a couple of beats, and that happens to be when the drawbridge falls. Perhaps the music changes into a section with lots of varied percussive elements, just as you reach the rotating platform area, and it feels like the percussion is emulating the mechanics of the moving machines.
Let The Music Drive Experimentation
Hooking up these level design elements to the music also allows for some fast experimentation. This is one big point that stuck out to me at GDC 2011. Steph Thirion, in his Indie Games Summit talk “Game Design by Accidents”, talked about the power of tweaking variables that manipulate the entire feel of a game and how you can come across happy accidents. For instance, you could take my prototype level with drawbridges and rotating blocks that operate on beat and apply a music track that has a changing tempo. What happens when the tempo changes while you’re navigating the tricky rotating block section? Perhaps you’ll find the level is a lot more fun at a slower or faster tempo. Try throwing in a speed-metal song, then a dirge. I really want to hear level designers talking about the tempo of their levels!
The Time Grid
Games would benefit from a system that acts like the timeline in film editing. Games should be allowed the pacing and synchronization that linear audio/visual mediums like film and TV enjoy. A metronome can be this tool; it can act like a grid on which to align events on the “time” axis. Too many time decisions in games are based on random numbers of seconds. Let’s try to lock these down more and unify them.
Some great moments in film are accentuated by camera cuts happening on the beat of the music. The example that comes to mind, while probably not the most pleasant, is in "Requiem for a Dream." Actually, most movie trailers do this very well.
But It’s Hard!
I understand that integrating a system like this in every engine would cost some time and money, but I’ve also witnessed great coders write up basic metronome type systems in a day. I think the initial investment is worth it because of the inspiring ideas and possibilities that can come from it! Also, if the system is built modularly enough, it should be easily portable to any future games created with that toolset. So while it can take some programmer hours to get a metronome system up and running, I believe it can really pay off in the design phase.
You Can Do It
I’ve seen the metronome inspire design. A level for a game I worked on was based in a factory, and the level designer created a new type of platform for this level that resembled a toggle switch on an old metal computer console. The lead designers at the publisher asked for something interesting to happen with the toggle switch, else remove it. Meanwhile, I was in the level and had created a bunch of metal factory type one-shots, like drills, metal hits and steam whistles and wanted to play them to the beat with the metronome. I didn’t want them to start right away and risk them being too closely associated with the music, so I hooked into the switch and and made it so a whistle blew when the switch was jumped on, and the rhythmic clanging of the factory one-shots started a beat or two later. It was a success, and the publisher asked for it to be recreated across the entire level.
Call To Action
Alright gang, time to go out there and ask your team really nicely for (demand a) metronome system. Ask for one that can change BPM on the fly along with your background music. Ask for one that can send out messages every beat or fraction thereof. Ask for the ability to start particle effects on beat for those flashy moments.
Dig into scripting and start implementing the metronome in prototype levels to show off what it can do. Don’t keep it all to yourself, though! It’s up to you to present it to the design team and show them the strengths and possibilities of the metronome. Help them start using it as a design tool. Of course, you’ll need to support their designs with temp music and sounds, so get ready for that!
Feel free to ask (below in the comments) if I can explain myself better for you. I would like to elaborate more on this topic in the future when I can get better visual aids. Also, please let me know if you do any work with a metronome in your games projects. I'd love to hear them! I appreciate you reading the article and hope we all can work with a metronome system again very soon!
Bobby Arlauskas is a sound designer at GL33k, a game audio company based in Austin, TX, a member of the Tiger Style Games team and creates music under the name 'Kidko'