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.
--HG--
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%404237
Force Feedback for SDL
by Edgar Simo, mentored by Ryan C. Gordon
--HG--
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%403159