Mark Cooke’s G-Mixer

It’s that time of the year again and the exciting Independent Games Festival (IGF) is here. I’ll be judging for the fourth year running and have already started evaluating the games I have been assigned for the first round.

Once again games from all over the world have been submitted. Although not all games that are submitted are destined for success it is inspiring to see the creativity at work in so many of these titles. The list of 226 entrants for the main competition is available here.

It is awesome to see that Barkley, Shut-up and Jam: Gaiden the insane basketball, Charles Barkley, RPG mash-up is on the list. Here’s a quote describing a portion of the plot of the game on Wikipedia to give you a taste:

When they arrive, Cyberdwarf suggests that B.L.O.O.D.M.O.S.E.S. has likely used the “Ultimate B-Ball” to perform the Chaos Dunk, so they visit the old Spalding Building in Proto Neo New York — where it is rumored that an extremely powerful basketball was being created before the Purge. The party reaches the sewer ladder leading to Proto Neo New York, but find that Dr. Allard — a cosmetic surgeon profitting off of Cesspool X’s citizens — has a guard posted at the ladder, demanding a fee of five thousand neo shekels for passage into Proto Neo New York.

Pure nonsensical awesome. I love it! This is just a fun example of the kind of games that the IGF is able to showcase when there are no creative, financial, or market limits. I haven’t played “Gigolo Assassin” yet but I love the name and doubt any game named that would ever see a retail release. The IGF brings publicity to games that might otherwise never get it even if they deserve it. That’s why I feel proud to be a part of the process.

A number of well known entries are also participating this year, including: Pixel Junk Eden, Pixel Junk Monsters, Cortex Command, Dino Run, and Forumwarz to name a few.

It will be another great year.

Sound playback latency on PCs sucks. Or I am doing something completely wrong.

For a while I have been working on and off on the audio tech for a game I am making in my free time. The game part hasn’t progressed much due to getting hung up in the minutia of sound programming.

The problem is that I want millisecond accurate sound quantizing – meaning that I want to play a sound back exactly at a specific time. The purpose of this is to string a large set of separate individual sounds together to make music. For example, playing a kick drum on the first and third beat of a bar, a snare on two and four, and a high-hat on every eighth note.

What you end up with is kind of a mess due to variable sound latency in the API, OS, and sound driver. When my program says “play this right now” it’s impossible to know when the sound will actually be audible at the speakers. It kinda sounds right but there is audible error. The error becomes more and more obvious when trying to align two sounds on the same beat. I don’t mean playing two sounds on the same frame in code – that gives good results. What I mean is that if I have a beat loop playing for quite some time and I’m tracking it on my internal timeline then trying to play other sounds that match to that loop is a challenge due to variable latency.

Here’s a visual illustration:

Basic timeline w/ eighth notes as smallest division.

Times I play back sound algorithmically.

What you actually hear.

Notice how in the final image the distance between the timeline position and when you hear the sound is different every time a sound is played. You can’t accurately reverse compensate for the error, i.e. by playing the sound slightly before you actually want it to be heard, because the latency is always changing. (Framerate is a component of this latency and can be compensated for, if your framerate is generally stable, but it is not the only component.)

I have written this piece of software twice, once with C#/XNA and once with C++/DirectSound. XNA would be ideal but there is an additional 10 milliseconds or so latency on top of using DirectSound. Regardless, neither work to my satisfaction.

In normal game scenarios this variable sound latency, which averages around 50 milliseconds in a rough estimate on my questionable hardware, is unnoticeable. This is simply because the sounds are independent events that do not need to be timed and aligned with other events in the game’s sound environment.

I’m thinking this kind of accurate system can only work where the software is filling out a sound buffer ahead of where the buffer is being played back in the sound file. A dynamically generated sound stream. That rules out using XNA unfortunately which offers no low-level sound buffer access through its API. I’m not sure how far ahead the software will need to write into the sound buffer to stay in front of the playback head. If I can guarantee a stable framerate theoretically it would be just 1-2 frames. To account for spikes in framerate or OS unpredictability I’m sure being further ahead is necessary. This also opens the door to having to mix all the individual sounds myself in a single sound buffer which sounds like a nightmare.

The whole point of my game idea is that I want realtime musical response to what the player is doing in the game. Not like Guitar Hero or a dynamic music system that fades between a few preset tracks. Rather, to capture the feeling of the player creating the music, at a micro per-instrument level, through their play in a fast paced action game. Changing the music changes the game state, play field, and visuals. Therefore I need to be able to change the music both quickly for realtime response and to ensure that my changes are on time and harmonize with the other sounds.

I want to capture the feeling that the player is both playing this game but is also acting as a creator within it, directing the music and visuals as they go. Hopefully I can find a solution that will let me get past this and finally delve further into the game and sound design which is what I really want to do be doing.

According to Kotaku, apparently the future of iPhone games involves playing Nihilistic/THQ’s Conan – the last game I worked on that shipped – and using the touch controls for perversions! Excellent!

I recently completed the short demo of the new EA/DICE game Mirror’s Edge. It’s a first-person parkour run-jump game that is done very well. I’m looking forward to it.

What struck me as interesting from a sales perspective was that there is some locked content in the demo. The only way to access the content – a bonus time trial level – is to pre-order the game and enter an unlock code. Some may look at it as evil. That it is content that should have been available in the demo for anyone to access. They would be wrong though.

This is a slick trick and is likely having a positive pre-sale effect due to the strength of the demo. The game runs and looks great and will leave a lot of gamers looking for more. If they are willing to part with their money early then they can get more. It’s right there waiting for them.

I can’t say whether or not this is an original marketing gimmick or not. When tied with a strong demo though I have to imagine it works well to drive up pre-sales for the title. Having more pre-sales in turn can drive up shelf space at brick and mortar retail locations which will likely result in more sales down the line due to extended presence in stores. Well played!