Graphics Reference
In-Depth Information
Chapter 8
Bullet Physics and the Blender Game Engine
Blender is a unique 3D animation suite in that it contains a full-featured game engine for the creation of games
and other free-standing interactive content. Nevertheless, in spite of its core of devoted fans, the game engine is
an all-too-often overlooked feature of Blender.
In this chapter, you'll learn the basics of working with Bullet Physics in the BGE to the point that you can easily
create dynamic rigid body animations, which can then be used in the Blender animation environment you're ac-
customedto.IfyouarenewtoBGE,youwillbesurprisedbyhowmuchamazingfunctionalityitwillopenupfor
you. If not, this chapter should provide some interesting ideas for how to integrate real-time generated physics
simulations with rendered animations.
In this chapter, you will learn to
• Use the appropriate collision bounds for what you need
• Experiment with cutting-edge physics features
• Take ragdoll physics to the next level with Bullet integration
Physics in the BGE
It goes without saying that for people who are mainly interested in creating games, the game engine is one of
Blender's major attractions. The BGE is widely used by hobbyist game creators and as a basis for real-time, in-
teractive visualization.
As everybody who's ever played a game knows, game worlds can be pretty rough-and-tumble places. Cars
crash, walls crumble, and bad guys go flying across rooms. This is all made possible by physics simulation, and
any quality game-creation tool these days needs a good real-time Newtonian physics library. For Blender, this is
the open-source Bullet Physics Library. Indeed, Blender is not alone in this; the Bullet Physics Library, authored
by Erwin Coumans, simulation lead at Sony Computer Entertainment America, is being used by professional
game developers with parallel optimizations for PlayStation 3 and Xbox 360. The companies that use Bullet are
able to contribute back to Bullet under the zlib license.
Bullet was showcased in an entertaining way in the Bullet Physics Contest 2007, in which contestants com-
peted to create the most impressive Rube Goldberg machine in BGE. Some stills from Christopher Plush's win-
ning machine can be seen in
Figure 8-1
.
Since then, a variety of improvements and additions have been intro-
duced to the Bullet library.
