Joe 2009-11-23 21:31:10 PST If type is ::SDL_HAPTIC_CARTESIAN, direction is encoded by three positions 367 * (X axis, Y axis and Z axis (with 3 axes)). ::SDL_HAPTIC_CARTESIAN uses 368 * the first three \c dir parameters. The cardinal directions would be: 369 * - North: 0,-1, 0 370 * - East: -1, 0, 0 371 * - South: 0, 1, 0 372 * - West: 1, 0, 0 typedef struct SDL_HapticDirection { Uint8 type; /**< The type of encoding. */ Uint16 dir[3]; /**< The encoded direction. */ } SDL_HapticDirection; An unsigned int can't store negative values and I don't see an alternate way to encode them in the docs or source. The best I have been able to come up with is using a negative magnitude for the effect but this will only get me 2 of the 4 quadrants in the plane for 2d effects. I looked at the win32 and linux implementations and I believe is is safe to use signed ints in the direction struct. I am unfamiliar with the darwin haptics API so I don't know if it is safe.