March 26, 2004

Welcome mah friends, to another weekly look inside the machinery of Bungie Towers. Enjoy. Or be mildly distracted. Whichever.

Mon Frere!

Michel (who's a handsome French Canadian and a huge hit with the ladeez thanks to his combination of Gallic charm, sexy accent and excellent nationalized health care system AND the angriest 23-year old in the world) talked to me about moving BSPs today. A BSP is a Binary Separation Plane, or in other words, a great big chunk of level. The thing about a BSP is that it's all one giant piece (they can be small too) that's interconnected and joined at every seam. That means it's all rendered in one go, and can be manipulated at will – if there's enough processor power. And that's been one of the things the team has been optimizing – big moving BSPs.

The BSPs in question contain some future surprises, but a good example would be say, a drawbridge (nope, the bridge we talked about a couple of updates ago is NOT a drawbridge) with like, a tollbooth, some gun emplacements and a bouncy castle. It's one thing to draw those objects as a Static BSP – quite another to move them around. Optimizing things like that frees up more processor power for AI and other tasks, so it's important to get it done before the gameplay is tuned on those levels.

It's also a weird mix of programming and design – since in a way, a moving BSP acts more like a character or a vehicle than a building or a level. Often the various departments can just get along with polishing their bits, but in an instance like this, close-knit cooperation is a must.

Michel has also been working out the nuances of the weather system with the environment guys. Mmhmm. Weather system. It won't be a big surprise to say that there's going to be rain and snow (it is Earth after all) but weather isn't always wet and cold. One level is set in a dry climate where dust, wind and sand all play a part. Filling out the levels with weather makes a tremendous difference to how "alive" the spaces feel. The snow and swamp levels in the original game are still some of my favorite levels. Rumors of a lava and minecart level are to be ignored.

March 19 2004 We have a couple of important guests coming in today, so the update is tight and taut, not to mention shorter than usual. Environment! The environment artists comprise my favorite area at Bungie. Why? Because they speak in a language I can completely understand. "Look Frank, a building is kind of like a square with holes in it so people can walk in and out." Sure, they're patronizing me, and even making fun of my accent, but they still do cool stuff. Why just this morning I was admiring a building on an Earth level when I noticed that there was ivy hanging from it. It wasn't hanging there last week, and here it was, green and leafy. One of the artists pointed out something neat too the ivy only hangs on one side of the street, the shady side. That's because ivy won't grow in ferocious, constant sunlight, which is just one of those details that makes a place feel more real. Actually the shadows on one side of the street make for a compelling gameplay experience too, since your foes dart in and out of the shade, making themselves more difficult targets. Jerks! And that's just one example. The ivy in this case is just one of the things that are placed carefully in the world to make it more "organic," like shrubs and grass and plants and stuff. The ivy is actually a BSP (Binary Separation Plane) with an alpha channel to make the gaps between the leaves transparent, but not all decorators will use this technique, some will be 2D sprites, some shader effects and others simply textures. Basically whatever looks best in any given circumstance, or causes the least impact on processor overhead. The levels shown featured very nice lightmaps, but look even more impressive with the addition of dynamic lights, everything that's turned on improves the big picture. Animation! The Animators have been going through lots of different animations, tweaking, tuning and adjusting some for purely aesthetic reasons and some tied directly to gameplay. The short struggle that happens during vehicle boarding is just such an example. It has to be clear what's going on, and the animation has to be tied in directly with the pace of the game. All Bungie animations are hand-animated, and that's a time-consuming process. Motion capture has its advantages and disadvantages, but hand-animated stuff gives Bungie animators much more control over the process, and motion capture doesn't help when your character is a three foot alien with back problems.