I'm Morgan McGuire (@CasualEffects). I've been working on computer graphics and games for 20 years at great places including NVIDIA, University of Waterloo, Williams College, Brown University, Roblox, Unity, and Activision.

See my home page for a full index of my blog posts, books, research, and projects.

Tuesday, April 2, 2013

Spy Virtual Board Game

I've been working on a spy-themed virtual board game as a hobby project from a game jam last weekend.  Unfortunately, I had the flu and couldn't really complete the jam, but I did make enough progress on the game from scratch to become excited about it. It already served the purpose of helping to flush bugs and motivate new features for G3D, codeheart.js, and mongoose, the main libraries that it uses. I hope to put in work from time to time as a hobby project.

The game uses multiple screens. The main screen is the game board seen by everyone.  Each player also has a web browser (ideally on a multi-touch mobile device, but any HTML5 browser works) to view his or her private hand of cards and initiate actions. There are no controllers used except for these browsers.

Here's a photograph from the first time I successfully connected the mobile device to the main game using a QR code and an iPod's camera:


At that point, my goal was to make a 3D tactical game, inspired by XCOM.  The game quickly evolved into this virtual board game:

Main Screen

Mobile Screen

The switch to board game mechanics and visuals was initially motivated by the limited time that I had to create artwork for the game jam. However, as I started to map out the gameplay, I realized that the increased abstraction of a boardgame allows much deeper gameplay.  A tactical spy game at a simulation level would turn into Splinter Cell or Monaco (both fine games), where fine-detail movement, combat, lock picking, etc. dominated.  I wanted much higher-level and emergent gameplay, such as planting evidence, conversations, crafting (MacGuyver & A-Team style). Abstracting interactions (similar to Munchkin's abstraction of D&D encounters) allows the player's imagination to fill in details as well, and imagination is the best graphics (see Doom I, Alien, and...books, etc.).

Tonight I implemented the animations for characters picking up, dropping, and giving each other equipment, as shown in this video:


The current implementation is currently 1421 SLOC in C++ and JavaScript (including the object database) and about 3MB of image data files. That's tiny by most project standards but already large enough to concern me. Hobby projects bit-rot quickly because they aren't tested on daily as the underlying APIs evolve. This is also code with a substantial amount of multithreading, which greatly increases the logical complexity and risk that large amounts of code have bugs. There are about 10 threads active at all times to communicate with the mobile devices and load resources to them over asynchronous channels.  That's necessary, but also nine too many for comfort.

When I next have an evening to hack on this, the next step is debugging some instabilities arising from all of those threads. I can then move on to implementing actions taken using the fun equipment and skills that are currently in the game in name and stats only but don't yet function.


Morgan McGuire is a professor of Computer Science at Williams College and a professional game developer. He is the author of The Graphics Codex, an essential reference for computer graphics that runs on iPhone, iPad, and iPod Touch.

Posted by at