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We throw pie with a little help from our friends

Thursday, April 9, 2015

(Cross-posted with the Google Developers Blog)

Fun Propulsion Labs at Google* is back today with some new releases for game developers. We’ve updated Pie Noon (our open source Android TV game) with networked multi-screen action, and we’ve also added some delicious new libraries we’ve been baking since the original release: the Pindrop audio library and the Motive animation system.

Pie Noon multi-screen action

Got an Android TV and up to 4 friends with Android phones or tablets? You’re ready for some strategic multi-player mayhem in this updated game mode. Plan your next move in secret on your Android phone: will you throw at an opponent, block an incoming attack, or take the risky approach and wait for a larger pie? Choose your target and action, then watch the Android TV to see what happens!

We used the NearbyConnections API from the most recent version of Google Play Games services to easily connect smartphones to your Android TV and turn our original Pie Noon party game into a game of turn-based strategy. You can grab the latest version of Pie Noon from Google Play to try it out, or crack open the source code and take a look at how we used FlatBuffers to encode data across the network in a fast, portable, bandwidth-efficient way.

Pindrop: an open source game audio library

Pindrop is a cross-platform C++ library for managing your in-game audio. It supports cross compilation to Android, Linux, iOS and OSX. An early version of this code was part of the first Pie Noon release, but it’s now available as a separate library that you can use in your own games. Pindrop handles loading and unloading sound banks, tracking sound locations and listeners, prioritization of your audio channels, and more.

Pindrop is built on top of several other pieces of open source technology:

  • SDL Mixer is used as a backend for actually playing the audio.
  • The loading of data and configuration files is handled by our serialization library, FlatBuffers.
  • Our own math library, MathFu, is used for a number of under-the-hood calculations.

You can download the latest open source release from our GitHub page. Documentation is available here and a sample project is included in the source tree. Please feel free to post any questions in our discussion list.

Motive: an open source animation system

The Motive animation system can breathe life into your static scenes. It does this by applying motion to simple variables. For example, if you’d like a flashlight to shine on a constantly-moving target, Motive can animate the flashlight so that it moves smoothly yet responsively.

Motive animates both spline-based motion and procedural motion. These types of motion are not technically difficult, but they are artistically subtle. It's easy to get the math wrong. It's easy to end up with something that moves as required but doesn't quite feel right. Motive does the math and lets you focus on the feeling.

Motive is scalable. It's designed to be extremely fast. It also has a tight memory footprint -- smaller than traditional animation compression -- that's based on Dual Cubic Splines. Our hope is that you might consider using Motive as a high-performance back-end to your existing full-featured animation systems.

This initial release of Motive is feature-light since we focused our early efforts on doing something simple very quickly. We support procedural and spline-based animation, but we don't yet support data export from animation packages like Blender or Maya. Motive 1.0 is suitable for props -- trees, cameras, extremities -- but not fully rigged character models.  Like all FPL technologies, Motive is open source and cross-platform. Please check out the discussion list, too.

What’s Fun Propulsion Labs at Google?

You might remember us from such Android games as Pie Noon, LiquidFun Paint, and VoltAir, and such cross-platform libraries as MathFu, LiquidFun, and FlatBuffers.

Want to learn more about our team? Check out this recent episode of Game On! with Todd Kerpelman for the scoop!

by Jon Simantov, Fun Propulsion Labs at Google

* Fun Propulsion Labs is a team within Google that's dedicated to advancing gaming on Android and other platforms.

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