The basic geometry and math libraries used in ROS.

angles: Provides a set of simple math utilities to work with angles. The
utilities cover simple things like normalizing an angle and conversion between
degrees and radians, but also functions to calculate things like the shortest
angular distance between two joinst space positions of your robot, with the
joint motion constrained by joint limits.

bullet: Contains the Bullet professional free 3D Game Multiphysics Library. The
Bullet library provided by this ROS package is slightly different from the
official Bullet release.

eigen: This package contains the Eigen C++ template library for linear algebra.

KDL: This package contains the Kinematics and Dynamics Library (KDL),
distributed by the Orocos Project.

tf: This package lets you keep track of multiple coordinate frames over time.
tf maintains the relationship between coordinate frames in a tree structure
buffered in time, and lets the user transform points, vectors, etc between any
two coordinate frames at any desired point in time.

WWW: http://www.ros.org/wiki/geometry